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2. A Robust Multi-Level Design for Dirty-Paper Coding
- Author
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Yan Xin, Xiaodong Wang, Momin Uppal, Guosen Yue, and Zixiang Xiong
- Subjects
Theoretical computer science ,Concatenated error correction code ,Variable-length code ,List decoding ,Distributed source coding ,Dirty paper coding ,Forward error correction ,Electrical and Electronic Engineering ,Low-density parity-check code ,Algorithm ,Coding gain ,Mathematics - Abstract
We propose a robust close-to-capacity dirty-paper coding (DPC) design framework in which multi-level low density parity check (LDPC) codes and trellis coded quantization (TCQ) are employed as the channel and source coding components, respectively. The proposed design framework is robust in the sense that it yields close to capacity solutions in the high-, medium-, and low-rate regimes. This is in contrast to existing practical DPC schemes that perform well only in one or two of these regimes, but not all three. We design codes for transmission rates of 0.5, 1.0, 1.5, and 2.0 bits/sample (b/s) using one, two, three, and four LDPC levels; at a block length of 2×105, the codes perform 0.95, 0.58, 0.55, and 0.54 dB from the corresponding information theoretic limits, respectively. We also propose a low-complexity decoding scheme that does not involve iterative message passing between the source and channel decoders; the low-complexity scheme performs only 1.08, 0.85, and 0.79 dB away from the theoretical limits at transmission rates of 1.0, 1.5, and 2.0 b/s, respectively.
- Published
- 2013
3. Gain-Invariant Dirty Paper Coding for Hierarchical OFDM
- Author
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Michele Scagliola, Fernando Pérez-González, and Pietro Guccione
- Subjects
Computer science ,Orthogonal frequency-division multiplexing ,Equalization (audio) ,Hierarchical modulation ,Data_CODINGANDINFORMATIONTHEORY ,Subcarrier ,Digital Video Broadcasting ,Electronic engineering ,Dirty paper coding ,Electrical and Electronic Engineering ,Quadrature amplitude modulation ,Decoding methods ,Multipath propagation ,Computer Science::Information Theory ,Communication channel - Abstract
A novel approach is here presented to superimpose a low-priority data stream on a high-priority data stream for OFDM systems. The main improvement with respect to conventional hierarchical modulation, which is included with the same purpose in various wireless technologies, is that the low-priority data stream can be decoded from the received subcarrier symbols without any previous equalization for multipath fading channels. As a consequence, the expected performance is nearly invariant of the channel estimation method used to equalize the channel. The low-priority stream is inserted adopting a gain-invariant dirty paper coding based on Rational Dither Modulation, which was proposed for data hiding applications. In this paper an analysis of the developed system is presented and several simulations have been carried out using DVB-T system parameters to verify the validity of the proposed approach. The experimental results show the better performance of the proposed method with respect to that of a conventional hierarchical modulation, particularly when the accuracy of the estimated channel response decreases.
- Published
- 2011
4. Toward a Practical Scheme for Binary Broadcast Channels with Varying Channel Quality Using Dirty Paper Coding
- Author
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Chih-Chun Wang and Gyu Bum Kyung
- Subjects
Quantization (signal processing) ,Binary number ,Data_CODINGANDINFORMATIONTHEORY ,Binary erasure channel ,Binary symmetric channel ,Electronic engineering ,Binary code ,Dirty paper coding ,Electrical and Electronic Engineering ,Algorithm ,Decoding methods ,Computer Science::Information Theory ,Mathematics ,Communication channel - Abstract
We consider practical schemes for binary dirty-paper channels and broadcast channels (BCs) with two receivers and varying channel quality. With the BC application in mind, this paper proposes a new design for binary dirty paper coding (DPC). By exploiting the concept of coset binning, the complexity of the system is greatly reduced when compared to the existing works. Some design challenges of the coset binning approach are identified and addressed. The proposed binary DPC system achieves similar performance to the state-of-the-art, superposition-coding-based system while demonstrating significant advantages in terms of complexity and flexibility of system design. For binary BCs, achieving the capacity generally requires the superposition of a normal channel code and a carefully designed channel code with non-uniform bit distribution. The non-uniform bit distribution is chosen according to the channel conditions. Therefore, to achieve the capacity for binary BCs with varying channel quality, it is necessary to use quantization codes of different rates, which significantly increases the implementation complexity. In this paper, we also propose a broadcast scheme that generalizes the concept of binary DPC, which we term soft DPC. By combining soft DPC with time sharing, we achieve a large percentage of the capacity for a wide range of channel quality with little complexity overhead. Our scheme uses only one fixed pair of codes for users 1 and 2, and a single quantization code, which possesses many practical advantages over traditional time sharing and superposition coding solutions and provides strictly better performance.
- Published
- 2011
5. Rate Allocation for Cooperative Orthogonal-Division Channels with Dirty-Paper Coding
- Author
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Cho Yiu Ng, Chi Wan Sung, Tat-Ming Lok, and Kenneth W. Shum
- Subjects
Channel code ,Diversity gain ,Computer science ,Electronic engineering ,Dirty paper coding ,Electrical and Electronic Engineering ,Antenna diversity ,Algorithm ,Decoding methods ,Computer Science::Information Theory ,Communication channel ,Cooperative diversity - Abstract
This paper investigates how much the rate region of the two-user Gaussian interference channel can be enlarged by allowing the two source nodes to cooperate. Two cooperative transmission schemes are proposed, based on dirty-paper coding and the assumption that the radio bandwidth is partitioned into two parts, and each part is utilized by one source node. The achievable rate regions and the outage performance of these two schemes are compared with the simplified Han-Kobayashi scheme, which is an efficient coding scheme for the interference channel. Simulation results show that in some channel realizations, the rate region of the Han-Kobayashi scheme is a subset of the rate regions of our two proposed cooperative transmission schemes. Furthermore, a significant gain in outage performance can be obtained, as the cooperative schemes have twice the diversity order of the simplified Han-Kobayashi scheme. While both cooperative schemes are able to yield large diversity gain, one of them can be implemented by simple decoder. Besides, it has an efficient algorithm for maximizing its weighted sum rate, and can be extended easily to the multi-channel case.
- Published
- 2010
6. An efficient greedy scheduler for zero-forcing dirty-paper coding
- Author
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Chunqi Chang, Zhongfu Ye, Yeung Sam Hung, and Jisheng Dai
- Subjects
Householder transformation ,Mathematical optimization ,Computational complexity theory ,MIMO ,Dirty paper coding ,Data_CODINGANDINFORMATIONTHEORY ,Parallel computing ,Electrical and Electronic Engineering ,Bottleneck ,QR decomposition ,Mathematics ,Matrix decomposition ,Scheduling (computing) - Abstract
In this paper, an efficient greedy scheduler for zero-forcing dirty-paper coding (ZF-DPC), which can be incorporated in complex Householder QR factorization of the channel matrix, is proposed. The ratio of the complexity of the proposed scheduler to the complexity of the channel matrix factorization required by ZF-DPC is O(M-1), while such ratio for the original greedy scheduler is O(M), where M is the number of transmitters. Therefore, the new scheduler reduces the overhead of scheduling from being the bottleneck of ZF-DPC to being negligible.
- Published
- 2009
7. On the robustness of dirty paper coding
- Author
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Uri Erez and Anatoly Khina
- Subjects
Engineering ,Estimation theory ,business.industry ,Transmitter ,Topology ,Upper and lower bounds ,Robustness (computer science) ,Channel state information ,Electronic engineering ,Dirty paper coding ,Electrical and Electronic Engineering ,business ,Scaling ,Computer Science::Information Theory ,Coding (social sciences) - Abstract
A dirty-paper channel is considered, where the transmitter knows the interference sequence up to a constant multiplicative factor, known only to the receiver. Lower bounds on the achievable rate of communication are derived by proposing a coding scheme that partially compensates for the imprecise channel knowledge.We focus on a communication scenario where the signal-to-noise ratio is high. Our approach is based on analyzing the performance achievable using lattice-based coding schemes. When the power of the interference is finite, we show that the achievable rate of this lattice-based coding scheme may be improved by a judicious choice of the scaling parameter at the receiver. We further show that the communication rate may be improved, for finite as well as infinite interference power, by allowing randomized scaling at the transmitter.
- Published
- 2010
8. Practical Dirty Paper Coding With Sum Codes
- Author
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Kiran M. Rege, Krishna Balachandran, M. Kemal Karakayali, and Joseph H. Kang
- Subjects
Block code ,021110 strategic, defence & security studies ,Theoretical computer science ,Concatenated error correction code ,0211 other engineering and technologies ,Variable-length code ,020206 networking & telecommunications ,Data_CODINGANDINFORMATIONTHEORY ,02 engineering and technology ,Linear code ,Systematic code ,Cyclic code ,0202 electrical engineering, electronic engineering, information engineering ,Constant-weight code ,Electrical and Electronic Engineering ,Low-density parity-check code ,Algorithm ,Computer Science::Information Theory ,Mathematics - Abstract
In this paper, we present a practical method to construct dirty paper coding (DPC) schemes using sum codes. Unlike the commonly used approach to DPC where the coding scheme involves concatenation of a channel code and a quantization code, the proposed method embodies a unified approach that emulates the binning method used in the proof of the DPC result. Auxiliary bits are used to create the desired number of code vectors in each bin. Sum codes are obtained when information sequences augmented with auxiliary bits are encoded using linear block codes. Sum-code-based DPC schemes can be implemented using any linear block code, and entail a relatively small increase in decoder complexity when compared to standard communication schemes. They can also lead to significant reduction in transmit power in comparison to standard schemes.
- Published
- 2016
9. Weighted Sum Rate Maximization for MIMO Broadcast Channels Using Dirty Paper Coding and Zero-forcing Methods
- Author
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Mats Bengtsson, Bjorn Ottersten, Le-Nam Tran, and Markku Juntti
- Subjects
Mathematical optimization ,Optimization problem ,Rank (linear algebra) ,05 social sciences ,050801 communication & media studies ,020206 networking & telecommunications ,02 engineering and technology ,Maximization ,Precoding ,QR decomposition ,0508 media and communications ,Singular value decomposition ,0202 electrical engineering, electronic engineering, information engineering ,Dirty paper coding ,Relaxation (approximation) ,Electrical and Electronic Engineering ,Computer Science::Information Theory ,Mathematics - Abstract
We consider precoder design for maximizing the weighted sum rate (WSR) of successive zero-forcing dirty paper coding (SZF-DPC). For this problem, the existing precoder designs often assume a sum power constraint (SPC) and rely on the singular value decomposition (SVD). The SVD-based designs are known to be optimal but require high complexity. We first propose a low-complexity optimal precoder design for SZF-DPC under SPC, using the QR decomposition. Then, we propose an efficient numerical algorithm to find the optimal precoders subject to per-antenna power constraints (PAPCs). To this end, the precoder design for PAPCs is formulated as an optimization problem with a rank constraint on the covariance matrices. A well-known approach to solve this problem is to relax the rank constraints and solve the relaxed problem. Interestingly, for SZF-DPC, we are able to prove that the rank relaxation is tight. Consequently, the optimal precoder design for PAPCs is computed by solving the relaxed problem, for which we propose a customized interior-point method that exhibits a superlinear convergence rate. Two suboptimal precoder designs are also presented and compared to the optimal ones. We also show that the proposed numerical method is applicable for finding the optimal precoders for block diagonalization scheme.
- Published
- 2013
- Full Text
- View/download PDF
10. — Invited Paper — Backscatter Communication and RFID: Coding, Energy, and MIMO Analysis
- Author
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Sumit Roy and Colby Boyer
- Subjects
Engineering ,business.industry ,MIMO ,Electrical engineering ,Spectral efficiency ,Spatial multiplexing ,Design choice ,Electronic engineering ,Radio-frequency identification ,Fading ,Electrical and Electronic Engineering ,business ,Energy harvesting ,Rayleigh fading - Abstract
Radio Frequency IDentification (RFID) is intended to supplant legacy (optical) bar code scanning technology found in many logistic and retail applications. RFID is distinguished by inexpensive, low power and compact form factor tags, whose longevity and efficacy are predicated on using passive communication techniques and on-tag power harvesting. Such tags employ backscatter modulation, which does not require any active RF components. As a result, backscatter has become an attractive design choice for short-range communications in power constrained wireless sensor networking scenarios. The purpose of this work is two-fold. First, it aims to expose backscatter communication as an emerging topic to a communication systems-theoretic audience. Since backscatter modulation and on-tag power harvesting efficiency are coupled, it is necessary to re-examine notions of power and spectral efficiency from an energy-constraint perspective; this leads to novel coded modulation schemes for future RFID systems. Further, we investigate RFID MIMO systems where the channel fading encountered has different statistics than the classical Rayleigh fading model. In turn,the trade off between diversity order and spatial multiplexing gains are distinct from wide-area MIMO.
- Published
- 2014
11. Source-channel rate optimization for progressive image transmission over block fading relay channels [Transactions Papers
- Author
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Pamela C. Cosman, R. Annavajjala, Hobin Kim, and Laurence B. Milstein
- Subjects
Computer science ,Throughput ,Data_CODINGANDINFORMATIONTHEORY ,Upper and lower bounds ,Multiplexing ,Error exponent ,law.invention ,Frequency-division multiplexing ,Relay ,law ,Computer Science::Networking and Internet Architecture ,Electronic engineering ,Fading ,Electrical and Electronic Engineering ,Computer Science::Information Theory ,Rayleigh fading ,Channel code ,ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS ,Code rate ,Antenna diversity ,Bit error rate ,Algorithm ,Relay channel ,Decoding methods ,Communication channel ,Phase-shift keying - Abstract
In this paper, we are concerned with the design and analysis of joint source-channel coding schemes for block fading channels with relay-assisted distributed spatial diversity. Assuming a progressive image coder with a constraint on the transmission bandwidth, we formulate a joint source-channel rate allocation scheme that maximizes the expected source throughput. Specifically, using Gaussian as well as BPSK inputs on flat Rayleigh fading channels, we lower bound the average packet error rate by the corresponding mutual information outage probability, and derive the average throughput expression as a function of channel code rates as well as channel SNR for both a frequency-division multiplexing-based baseline system without relaying, and a half-duplex relay system with a decode-and- forward protocol. At high signal-to-noise ratio (SNR), for the systems considered in this paper, we show that our rate optimization problem is a convex function of the channel code rates, and we show that a known recursive algorithm can be used to predict the performance of both systems.
- Published
- 2010
12. Construction of non-binary quasi-cyclic LDPC codes by arrays and array dispersions - [transactions papers
- Author
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Jingyu Kang, Shumei Song, Khaled Abdel-Ghaffar, Shu Lin, Bo Zhou, and Meina Xu
- Subjects
Block code ,Concatenated error correction code ,BCJR algorithm ,Turbo code ,Tornado code ,Data_CODINGANDINFORMATIONTHEORY ,Serial concatenated convolutional codes ,Electrical and Electronic Engineering ,Low-density parity-check code ,Linear code ,Algorithm ,Computer Science::Information Theory ,Mathematics - Abstract
This paper presents two algebraic methods for constructing high performance and efficiently encodable nonbinary quasi-cyclic LDPC codes based on arrays of special circulant permutation matrices and multi-fold array dispersions. Codes constructed based on these methods perform well over the AWGN and other types of channels with iterative decoding based on belief-propagation. Experimental results show that over the AWGN channel, these non-binary quasi-cyclic LDPC codes significantly outperform Reed-Solomon codes of the same lengths and rates decoded with either algebraic hard-decision Berlekamp-Massey algorithm or algebraic soft-decision Kotter-Vardy algorithm. Also presented in this paper is a class of asymptotically optimal LDPC codes for correcting bursts of erasures. Codes constructed also perform well over flat fading channels. Non-binary quasi-cyclic LDPC codes have a great potential to replace Reed-Solomon codes in some applications in communication environments and storage systems for combating mixed types of noises and interferences.
- Published
- 2009
13. Further results on noncoherent block-coded MPSK [transactions papers]
- Author
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Ruey-Yi Wei and Yen-Ming Chen
- Subjects
Block code ,Theoretical computer science ,Search algorithm ,Rotational invariance ,Algorithm design ,Electrical and Electronic Engineering ,Space–time code ,Algorithm ,Decoding methods ,Block (data storage) ,Mathematics ,Phase-shift keying - Abstract
A novel noncoherent block coding scheme, called noncoherent block-coded MPSK (NBC-MPSK), was proposed recently. In this paper, we present further research results on NBC-MPSK. We first focus on the rotational invariance (RI) of NBC-MPSK. Based on the RI property of NBC-MPSK with multistage decoding, a noncoherent near-optimal linear complexity multistage decoder for NBC-MPSK is proposed. Then we investigate a tree-search ML decoding algorithm for NBCMPSK. The derived algorithm is shown to have low complexity and excellent error performance. In this paper, we also utilize the idea of the NBC-MPSK to design noncoherent space-time block codes, called noncoherent space-time block-coded MPSK (NSTBC-MPSK). For two transmit antennas, we propose a signal set with set partitioning and derive the minimum noncohent distance of NSTBC-MPSK with this signal set. For the decoding of NSTBC-MPSK, we modify the ML decoding algorithm of NBC-MPSK and propose an iterative hard-decision decoding algorithm. Compared with training codes and unitary space-time modulation, NBC-MPSK and NSTBC-MPSK have larger minimum noncoherent distance and thus better error performance for the noncoherent ML decoder.
- Published
- 2008
14. Transactions Papers - Constructions of Nonbinary Quasi-Cyclic LDPC Codes: A Finite Field Approach
- Author
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Lan Lan, Ying Yu Tai, Shu Lin, Khaled Abdel-Ghaffar, Shumei Song, and Lingqi Zeng
- Subjects
Discrete mathematics ,Block code ,Concatenated error correction code ,BCJR algorithm ,Data_CODINGANDINFORMATIONTHEORY ,Serial concatenated convolutional codes ,Reed–Solomon error correction ,Turbo code ,Tornado code ,Electrical and Electronic Engineering ,Low-density parity-check code ,Algorithm ,Computer Science::Information Theory ,Mathematics - Abstract
This paper is concerned with construction of efficiently encodable nonbinary quasi-cyclic LDPC codes based on finite fields. Four classes of nonbinary quasi-cyclic LDPC codes are constructed. Experimental results show that codes constructed perform well with iterative decoding using a fast Fourier transform based q-ary sum-product algorithm and they achieve significant coding gains over Reed-Solomon codes of the same lengths and rates decoded with either algebraic hard- decision Berlekamp-Massey algorithm or algebraic soft-decision Kotter-Vardy algorithm.
- Published
- 2008
15. Transactions papers evaluation and design of irregular LDPC codes using ACE spectrum
- Author
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Vojin Senk and Dejan Vukobratovic
- Subjects
Theoretical computer science ,Heuristic (computer science) ,Graph theory ,Data_CODINGANDINFORMATIONTHEORY ,Hardware_PERFORMANCEANDRELIABILITY ,Binary erasure channel ,Physics::Space Physics ,Metric (mathematics) ,Graph (abstract data type) ,Algorithm design ,Electrical and Electronic Engineering ,Low-density parity-check code ,Error detection and correction ,Algorithm ,Computer Science::Information Theory ,Mathematics - Abstract
The construction of finite-length irregular LDPC codes with low error floors is currently an attractive research problem. In particular, for the binary erasure channel (BEC), the problem is to find the elements of selected irregular LDPC code ensembles with the size of their minimum stopping set being maximized. Due to the lack of analytical solutions to this problem, a simple but powerful heuristic design algorithm, the approximate cycle extrinsic message degree (ACE) constrained design algorithm, has recently been proposed. Building upon the ACE metric associated with a cycle in a code graph, we introduce the ACE spectrum of LDPC codes as a useful tool for evaluation of codes from selected irregular LDPC code ensembles. Using the ACE spectrum, we generalize the ACE constrained design algorithm, making it more flexible and efficient. We justify the ACE spectrum approach through examples and simulation results.
- Published
- 2009
16. Greedy scheduling performance for a zero-forcing dirty-paper coded system
- Author
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R.M. Buehrer, Jing Jiang, and William H. Tranter
- Subjects
Mathematical optimization ,Bounded function ,Real-time computing ,Telecommunications link ,Electrical and Electronic Engineering ,Greedy algorithm ,Multiplexing ,Fair-share scheduling ,Computer Science::Information Theory ,Mathematics ,Spatial multiplexing ,Scheduling (computing) ,Coding (social sciences) - Abstract
This letter presents two results for multiuser wireless systems employing dirty-paper coding strategies along with greedy scheduling over the broadcast multiple-input multiple-output channel. Specifically, an efficient and suboptimal downlink scheduler is proposed to approximate the maximum sum rate using equal power allocation, and it is shown to approach the maximum sum rate of optimal power allocation for a large number of users under optimal scheduling. The second result demonstrates that the average maximum sum rate can be tightly upper bounded when spatial multiplexing is maximized.
- Published
- 2006
17. The design of efficiently-encodable rate-compatible LDPC codes - [transactions papers]
- Author
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Aditya Ramamoorthy, Jaehong Kim, and Steven W. McLaughlin
- Subjects
Block code ,Puncturing ,Computer science ,Error floor ,Automatic repeat request ,Redundancy (engineering) ,Turbo code ,Tornado code ,Electrical and Electronic Engineering ,Low-density parity-check code ,Error detection and correction ,Linear code ,Algorithm - Abstract
We present a new class of irregular low-density parity-check (LDPC) codes for moderate block lengths (up to a few thousand bits) that are well-suited for rate-compatible puncturing. The proposed codes show good performance under puncturing over a wide range of rates and are suitable for usage in incremental redundancy hybrid-automatic repeat request (ARQ) systems. In addition, these codes are linear-time encodable with simple shift-register circuits. For a block length of 1200 bits the codes outperform optimized irregular LDPC codes and extended irregular repeat-accumulate (eIRA) codes for all puncturing rates 0.6~0.9 (base code performance is almost the same) and are particularly good at high puncturing rates where good puncturing performance has been previously difficult to achieve.
- Published
- 2009
18. Near-capacity turbo trellis coded modulation design based on EXIT charts and union bounds - [transactions papers]
- Author
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Soon Xin Ng, Osamah Alamri, Yonghui Li, Jorg Kliewer, and Lajos Hanzo
- Subjects
QAM ,Interleaving ,Diversity gain ,Electronic engineering ,Turbo code ,Context (language use) ,Fading ,Data_CODINGANDINFORMATIONTHEORY ,Electrical and Electronic Engineering ,Trellis modulation ,Algorithm ,Quadrature amplitude modulation ,Mathematics - Abstract
Bandwidth efficient parallel-concatenated Turbo Trellis Coded Modulation (TTCM) schemes were designed for communicating over uncorrelated Rayleigh fading channels. A symbol-based union bound was derived for analysing the error floor of the proposed TTCM schemes. A pair of In-phase (I) and Quadrature-phase (Q) interleavers were employed for interleaving the I and Q components of the TTCM coded symbols, in order to attain an increased diversity gain. The decoding convergence of the IQ-TTCM schemes was analysed using symbol-based EXtrinsic Information Transfer (EXIT) charts. The best TTCM component codes were selected with the aid of both the symbolbased union bound and non-binary EXIT charts, for designing capacity-approaching IQ-TTCM schemes in the context of 8 PSK, 16 QAM, 32 QAM and 64 QAM modulation schemes.
- Published
- 2008
19. Invited papers and timeliness of review process [editorial]
- Author
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Robert Schober
- Subjects
History ,Operations research ,Publishing ,business.industry ,Research areas ,Library science ,Review process ,Electrical and Electronic Engineering ,business ,Quarter (United States coin) ,Publication process - Abstract
This editorial to informs readers about a new initiative - publishing invited papers on emerging research topics in communications by authors who are well known experts in their respective research areas - and about the timeliness of the review and publication process. It is noted that over the past year, The average sub-to-pub times improved from 66.3 weeks in the second quarter of 2012 to 44.5 weeks in the second quarter of 2013.
- Published
- 2014
20. Power Efficient IRS-Assisted NOMA
- Author
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Jiaheng Wang, Jianyue Zhu, Yongming Huang, Keivan Navaie, and Zhiguo Ding
- Subjects
FOS: Computer and information sciences ,Beamforming ,Computer science ,business.industry ,Information Theory (cs.IT) ,Computer Science - Information Theory ,020206 networking & telecommunications ,020302 automobile design & engineering ,02 engineering and technology ,medicine.disease ,Power (physics) ,Noma ,0203 mechanical engineering ,Transmission (telecommunications) ,Telecommunications link ,0202 electrical engineering, electronic engineering, information engineering ,medicine ,Wireless ,Dirty paper coding ,Electrical and Electronic Engineering ,business ,Algorithm ,Decoding methods ,Communication channel - Abstract
In this paper, we propose a downlink multiple-input single-output (MISO) transmission scheme, which is assisted by an intelligent reflecting surface (IRS) consisting of a large number of passive reflecting elements. In the literature, it has been proved that nonorthogonal multiple access (NOMA) can achieve the same performance as computationally complex dirty paper coding, where the quasi-degradation condition is satisfied, conditioned on the users’ channels fall in the quasi-degradation region. However, in a conventional communication scenario, it is difficult to guarantee the quasi-degradation, because the channels are determined by the propagation environments and cannot be reconfigured. To overcome this difficulty, we focus on an IRS-assisted MISO NOMA system, where the wireless channels can be effectively tuned. We optimize the beamforming vectors and the IRS phase shift matrix for minimizing transmission power. Furthermore, we propose an improved quasi-degradation condition by using IRS, which can ensure that NOMA achieves the capacity region with high possibility. For a comparison, we study zero-forcing beamforming (ZFBF) as well, where the beamforming vectors and the IRS phase shift matrix are also jointly optimized. Comparing NOMA with ZFBF, it is shown that, with the same IRS phase shift matrix and the improved quasi-degradation condition, NOMA always outperforms ZFBF. At the same time, we identify the condition under which ZFBF outperforms NOMA, which motivates the proposed hybrid NOMA transmission. Simulation results show that the proposed IRS-assisted MISO system outperforms the MISO case without IRS, and the hybrid NOMA transmission scheme always achieves better performance than orthogonal multiple access.
- Published
- 2021
21. The Distortions Region of Broadcasting Correlated Gaussians and Asymmetric Data Transmission Over a Gaussian BC
- Author
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Shraga I. Bross
- Subjects
Computer science ,Gaussian ,020206 networking & telecommunications ,Data_CODINGANDINFORMATIONTHEORY ,02 engineering and technology ,Code rate ,symbols.namesake ,Transmission (telecommunications) ,Distortion ,0202 electrical engineering, electronic engineering, information engineering ,symbols ,Dirty paper coding ,Electrical and Electronic Engineering ,Algorithm ,Decoding methods ,Computer Science::Information Theory ,Data transmission - Abstract
A memoryless bivariate Gaussian source is transmitted to a pair of receivers over an average-power limited bandwidth-matched Gaussian broadcast channel. Based on their observations, Receiver 1 reconstructs the first source component while Receiver 2 reconstructs the second source component both seeking to minimize the expected squared-error distortions. In addition to the source transmission digital information at a specified rate should be conveyed reliably to Receiver 1–the “stronger” receiver. Given the message rate we characterize the achievable distortions region. Specifically, there is an ${\sf SNR}$ -threshold below which Dirty Paper coding of the digital information against a linear combination of the source components is optimal. The threshold is a function of the digital information rate, the source correlation and the distortion at the “stronger” receiver. Above this threshold a Dirty Paper coding extension of the Tian-Diggavi-Shamai hybrid scheme is shown to be optimal.
- Published
- 2020
22. Author's reply to 'A correction to Kurt Metzger's algorithm in the paper 'On the probability density of intersymbol interference' '
- Author
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K. Metzger
- Subjects
Intersymbol interference ,Theoretical computer science ,Transformation (function) ,Computer science ,Calculus ,Probability density function ,Electrical and Electronic Engineering - Abstract
Pokrajac and Nikoli (see ibid., vol.43, no.12, p.2868, 1995) have correctly identified a mistake by Metzger (see ibid., vol.COM-35, no.4, p.396-402). The examples presented by Metzger were calculated correctly, but the carelessness in the formulation of the equation is regretted. It was intended to show the feasibility of the basic transformation, and not to give an exhaustive investigation of the numerical possibilities for executing the equation. Some more sophisticated ways for performing the evaluation are included.
- Published
- 1997
23. Transceiver Design With UCD-Based Hybrid Beamforming for Millimeter Wave Massive MIMO
- Author
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Xiaohu You, Michail Matthaiou, Yuxing Lin, and Shi Jin
- Subjects
Beamforming ,Minimum mean square error ,060102 archaeology ,Computer science ,MIMO ,020206 networking & telecommunications ,06 humanities and the arts ,02 engineering and technology ,Spectral efficiency ,Interference (wave propagation) ,Transmission (telecommunications) ,Computer Science::Networking and Internet Architecture ,0202 electrical engineering, electronic engineering, information engineering ,Electronic engineering ,Bit error rate ,Baseband ,0601 history and archaeology ,Dirty paper coding ,Electrical and Electronic Engineering ,Computer Science::Information Theory ,Communication channel - Abstract
Hybrid transceiver designs for millimeter wave massive multiple-input multiple-output systems are feasible candidates to reduce the volume of radio frequency (RF) chains, decomposing the signal processing into the analog and digital domains. The existing schemes heavily depend on the singular value decomposition to obtain subchannels with uneven power gains, causing bit error rate (BER) performance degradation. In this paper, we propose a hybrid transceiver design based on the uniform channel decomposition (UCD), yielding subchannels with identical gains to improve the BER performance. Inspired by the UCD concept, we derive an equivalent optimization problem and propose two schemes, namely, phase-extraction and iterative update, to determine the RF beamformers, yielding an effective baseband channel with the greatest possible geometric mean of singular values. We apply the UCD with a minimum mean squared error criterion to complete the baseband beamforming. Finally, we combine the hybrid UCD beamforming with the vertical-Bell Labs layered space-time and dirty paper coding, to eliminate the inter-subchannel interference. An asymptotic analysis of the scheme performance is also pursued. The simulation results show that the proposed hybrid scheme outperforms the conventional schemes on the transmission BER, which achieves a spectral efficiency close to that of the fully-digital counterpart.
- Published
- 2019
24. A correction to Kurt Metzger's algorithm in the paper 'On the probability density of intersymbol interference'
- Author
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D. Pokrajac and Z. Nikolic
- Subjects
Intersymbol interference ,Operator (computer programming) ,Series (mathematics) ,Computer science ,Computation ,Linearity ,Probability density function ,Electrical and Electronic Engineering ,Error detection and correction ,Algorithm - Abstract
Using an operator approach this letter shows that Metzger's Algorithm for pdf computation (see ibid., vol. 35, pp. 396-402, Apr 1987) has an error in formula (15), which defines the procedure of generating the successive series of pdf approximation. A correction is given.
- Published
- 1995
25. Guide to Papers in This Issue
- Author
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James R. Wait
- Subjects
Engineering ,Directional antenna ,business.industry ,Electrical engineering ,Electrical and Electronic Engineering ,business ,Telecommunications - Published
- 1974
26. Joint State Estimation and Communication Over a State-Dependent Gaussian Multiple Access Channel
- Author
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Vinod M. Prabhakaran, Sibi Raj B Pillai, and Viswanathan Ramachandran
- Subjects
FOS: Computer and information sciences ,Access network ,Computer science ,Information Theory (cs.IT) ,Computer Science - Information Theory ,Gaussian ,020206 networking & telecommunications ,02 engineering and technology ,Telecommunications network ,symbols.namesake ,Analog signal ,0202 electrical engineering, electronic engineering, information engineering ,symbols ,Dirty paper coding ,State (computer science) ,Electrical and Electronic Engineering ,Algorithm ,Computer Science::Information Theory ,Communication channel - Abstract
A hybrid communication network with a common analog signal and an independent digital data stream as input to each node in a multiple access network is considered. The receiver/base-station has to estimate the analog signal with a given fidelity, and decode the digital streams with a low error probability. Treating the analog signal as a common state process, we set up a joint state estimation and communication problem in a Gaussian multiple access channel (MAC) with additive state. The transmitters have non-causal knowledge of the state process, and need to communicate independent data streams in addition to facilitating state estimation at the receiver. We first provide a complete characterization of the optimal trade-off between mean squared error distortion performance in estimating the state and the data rates for the message streams from two transmitting nodes. This is then generalized to an N-sender MAC. To this end, we show a natural connection between the state-dependent MAC model and a hybrid multi-sensor network in which a common source phenomenon is observed at N transmitting nodes. Each node encodes the source observations as well as an independent message stream over a Gaussian MAC without any state process. The receiver is interested estimating the source and all the messages. Again the distortion-rate performance is characterized., 12 pages, Journal submission
- Published
- 2019
27. Energy Efficiency Optimization With Interference Alignment in Multi-Cell MIMO Interfering Broadcast Channels
- Author
-
Jie Tang, Arman Shojaeifard, Emad Alsusa, Daniel K. C. So, and Khairi Ashour Hamdi
- Subjects
Green radio (GR) ,multiple-input multiple-output (MIMO) ,multicell MIMO interfering broadcast channel ,energy efficiency (EE) ,energy efficiency optimization ,subgradient method ,Receivers ,telecommunication power management ,Mathematics ,energy conservation ,search problems ,Signal to noise ratio ,interference suppression ,singular value decomposition ,bisection searching scheme ,MIMO ,intracell interference cancellation ,Array signal processing ,multiple input multiple output IFBC system ,Dirty paper coding ,signal-to-noise ratio ,intercell interference cancellation ,Algorithm ,gradient methods ,Efficient energy use ,Optimization ,cellular radio ,Maximum power principle ,channel coding ,SNR ,interference nulling ,Data_CODINGANDINFORMATIONTHEORY ,wireless channels ,Transmitting antennas ,multiple input multiple output (MIMO) ,dirty paper coding ,Singular value decomposition ,Electronic engineering ,MIMO communication ,Wireless ,Electrical and Electronic Engineering ,multiple access channel and broadcast channel duality principle ,Subgradient method ,hybrid DPC-IA approach ,Computer Science::Information Theory ,business.industry ,interference alignment ,radiofrequency interference ,Maximization ,water filling power adaptation scheme ,gradient-based power adaptation scheme ,Interference ,business - Abstract
Characterizing the fundamental energy efficiency (EE) performance of multiple-input-multiple-output interfering broadcast channels (MIMO-IFBC) is important for the design of green wireless system. In this paper, we propose a new network architecture proposition based on EE maximization for Multi-Cell MIMO-IFBC within the context of interference alignment (IA). Particularly, EE is maximized subject to maximum power and minimum throughput constraints. We propose two schemes to optimize EE for different signal-to-noise ratio (SNR) regions. For high-SNR operating regions, we employ a grouping-based IA scheme to jointly cancel intra- and inter-cell interferences and thus transform the MIMO-IFBC to a single-cell MIMO scenario. A gradient-based power adaptation scheme is proposed based on water-filling power adaptation and singular value decomposition to maximize EE for each cell. For moderate SNR cases, we propose an approach using dirty paper coding (DPC) with the principle of multiple access channel and broadcast channel duality to perform IA while maximizing EE in each cell. The algorithm in its dual form is solved using a subgradient method and a bisection searching scheme. Simulation results demonstrate the superior performance of the proposed schemes over several existing approaches. It also shows that interference-nulling-based IA approaches outperform hybrid DPC-IA approach in high-SNR region, and the opposite occurs in low-SNR region.
- Published
- 2015
28. Introduction to Papers on TDM/FDM Transmultiplexers
- Author
-
R. Kieburtz
- Subjects
business.industry ,Time-division multiplexing ,Computer science ,Electrical engineering ,Electronic engineering ,Electrical and Electronic Engineering ,MIMO-OFDM ,Statistical time division multiplexing ,business ,Multiplexing - Published
- 1978
29. Joint Level 2 and 3 Dynamic Spectrum Management for Downstream DSL
- Author
-
Marc Moonen, Jochen Maes, Mamoun Guenach, and Amir R. Forouzan
- Subjects
Engineering ,SISTA ,business.industry ,Transmitter ,Brute-force search ,Precoding ,Dynamic spectrum management ,Digital subscriber line ,Dirty paper coding ,Electrical and Electronic Engineering ,business ,Communication complexity ,Algorithm ,Decoding methods ,Computer network - Abstract
In this paper, we investigate joint level 2 and 3 dynamic spectrum management (joint DSM 2/3) for downstream (DS) DSL. We consider a DS scenario in which users are divided into a few separate groups, where vector encoding based signal coordination can be applied in each group and spectrum coordination is possible for all users. This can be seen as a mixed interference/broadcast channel (IF/BC) scenario. In order to obtain the optimal transmitter structure, we develop a generalized duality between the vector broadcast and multiple-access channel (MAC) for scenarios in which partial signal coordination is available among users. This theory together with optimal spectrum balancing (OSB) is exploited to calculate the jointly optimal filters and transmit powers for non-linear vector dirty paper coding structures (in the form of Tomlinson-Harashima precoder (THP)) in the groups. The proposed scheme is compared to several other joint DSM 2/3 algorithms for DS DSL. Simulation results show that the proposed scheme (referred to as the IF/BC-OSB algorithm) achieves considerably higher bit rates than the other schemes. IF/BC-OSB encompasses the earlier developed BC-OSB algorithm as a special case. A simplified version of IF/BC-OSB avoiding exhaustive search with near-optimal performance is also proposed. © 2012 IEEE. ispartof: IEEE Transactions on Communications vol:60 issue:10 pages:3111-3122 status: published
- Published
- 2012
30. The Effect of Imperfect Channel Knowledge on a MIMO System with Interference
- Author
-
Namjeong Lee, Joonhyuk Kang, and Osvaldo Simeone
- Subjects
Beamforming ,Engineering ,business.industry ,ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS ,Transmitter ,MIMO ,Data_CODINGANDINFORMATIONTHEORY ,Multi-user MIMO ,Transmission (telecommunications) ,Interference (communication) ,Channel state information ,Electronic engineering ,Dirty paper coding ,Electrical and Electronic Engineering ,business ,Computer Science::Information Theory - Abstract
A common model for transmission over wireless links is that of a multiantenna system affected by an additive interfering signal. In some scenarios of interest, such as when the interferer is located close to the transmitter and performs retransmission, interference may be learned by the transmitter, but remain unknown at the receiver. In this case, it is well known that, if transmitter and receiver have perfect channel state information (CSI), then a technique called Dirty Paper Coding (DPC) is able to fully mitigate the interference. This paper studies the impact of imperfect CSI on a multiple-input multiple-output (MIMO) system with interference and compares the performance of DPC with that of a scheme where interference is decoded at the receiver, which we refer to as beamforming with joint decoding (BF-JD). Unlike DPC, which models the interference as an "unstructured" random process, BF-JD exploits the fact that the interfering signal is a codeword of the interferer's codebook. It is demonstrated by analysis and numerical results that BF-JD provides advantages over DPC when CSI is imperfect at the transmitter but perfect at the receiver, whereas this is not true for the case of imperfect CSI at both transmitter and receiver.
- Published
- 2012
31. Required Transmit Power Applying Tomlinson-Harashima-Precoding in Scalar and MIMO Broadcast Systems
- Author
-
Carolin Huppert and Johannes Georg Klotz
- Subjects
Engineering ,Single antenna interference cancellation ,business.industry ,MIMO ,Electronic engineering ,Fading ,Dirty paper coding ,Electrical and Electronic Engineering ,business ,Transmitter power output ,Upper and lower bounds ,Precoding ,Quadrature amplitude modulation - Abstract
Tomlinson-Harashima-precoding can be used as dirty-paper-coding method for transmissions over a broadcast channel. However, applying it to the individual user messages the final transmit power may vary from the sum of single user powers. This paper investigates the required transmit power for Tomlinson-Harashima-precoding in two user broadcast systems. Additionally, upper and lower bounds on the required power are derived. First our considerations are done in scalar channels. Then we extend the results to MIMO systems. In order to judge the performance of THP applied as broadcast technique we finally determine the achievable user rates.
- Published
- 2010
32. Reduced feedback and random beamforming for OFDM MIMO broadcast channels
- Author
-
Babak Hassibi, M. Fakhereddin, and M. Sharif
- Subjects
Beamforming ,Engineering ,Orthogonal frequency-division multiplexing ,business.industry ,ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS ,Signal-to-interference-plus-noise ratio ,Data_CODINGANDINFORMATIONTHEORY ,Code rate ,Topology ,Subcarrier ,Computer Science::Performance ,Channel state information ,Telecommunications link ,Computer Science::Networking and Internet Architecture ,Electronic engineering ,Dirty paper coding ,Electrical and Electronic Engineering ,business ,Computer Science::Information Theory - Abstract
It has been shown that random beamforming using partial channel state information (CSI) achieves the same throughput scaling as obtained from dirty paper coding for a broadcast (downlink) channel with M transmit antennas and K users where K is large. In this paper, we apply this scheme to wideband MIMO broadcast channels. By using OFDM, an L-tap wideband channel can be decomposed to N parallel narrowband channels (subcarriers), where N > L . Neighboring subcarriers are highly correlated. Therefore, we consider neighboring subcarriers as a cluster and find the closed form solution for the joint characteristic function of SINR values at two subcarriers in a cluster. We show numerically how the knowledge of the quality of the center subcarrier sheds light about the quality of other subcarriers in the same cluster, and address the issue of cluster size. In addition, through complex and asymptotic analysis, we show that for cluster size of order N/L?(log K) (for large K), users need only feedback the best SINR at the center subcarrier of each cluster in order for the transmitter to perform opportunistic beamforming and maintain the same throughput scaling as when full CSI is available. Using simulation results, we verify our analytical result and show that even fewer feedback can be tolerated, and larger clusters (N/2L) can be implemented for a small throughput hit.
- Published
- 2009
33. How much does transmit correlation affect the sum-rate scaling of MIMO gaussian broadcast channels?
- Author
-
Tareq Y. Al-Naffouri, Babak Hassibi, and M. Sharif
- Subjects
Discrete mathematics ,Beamforming ,Spatial correlation ,Covariance matrix ,Gaussian ,MIMO ,symbols.namesake ,Channel state information ,Telecommunications link ,symbols ,Electronic engineering ,Dirty paper coding ,Electrical and Electronic Engineering ,Computer Science::Information Theory ,Mathematics - Abstract
This paper considers the effect of spatial correlation between transmit antennas on the sum-rate capacity of the MIMO Gaussian broadcast channel (i.e., downlink of a cellular system). Specifically, for a system with a large number of users n, we analyze the scaling laws of the sum-rate for the dirty paper coding and for different types of beamforming transmission schemes. When the channel is i.i.d., it has been shown that for large n, the sum rate is equal to M log log n + M log P/M + o(1) where M is the number of transmit antennas, P is the average signal to noise ratio, and o(1) refers to terms that go to zero as n rarr infin. When the channel exhibits some spatial correlation with a covariance matrix R (non-singular with tr(R) = M), we prove that the sum rate of dirty paper coding is M log log n + M log P/M + log det(R) + o(1). We further show that the sum-rate of various beamforming schemes achieves M log log n + M log P/M + M log c + o(1) where c les 1 depends on the type of beamforming. We can in fact compute c for random beamforming proposed in and more generally, for random beamforming with preceding in which beams are pre-multiplied by a fixed matrix. Simulation results are presented at the end of the paper.
- Published
- 2009
34. Differentiated rate scheduling for the down-link of cellular systems
- Author
-
M. Sharif, A.F. Dana, Ali Vakili, and Babak Hassibi
- Subjects
Beamforming ,Mathematical optimization ,Engineering ,business.industry ,ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS ,MIMO ,Signal-to-interference-plus-noise ratio ,Data_CODINGANDINFORMATIONTHEORY ,Code rate ,Scheduling (computing) ,Channel capacity ,Channel state information ,Computer Science::Networking and Internet Architecture ,Dirty paper coding ,Electrical and Electronic Engineering ,business ,Caltech Library Services ,Computer Science::Information Theory ,Computer network - Abstract
We consider the problem of differentiated rate scheduling for the downlink (i.e., multi-antenna broadcast channel), in the sense that the rates required by different users must satisfy certain constraints on their ratios. When full channel state information (CSI) is available at the transmitter and receivers, the problem can be readily solved using dirty paper coding (DPC) and the application of convex optimization techniques on the dual problem which is the multiple access channel (MAC). Since in many practical application full CSI may not be feasible and computational complexity prohibitive when the number of users is large, we focus on other simple schemes that require very little CSI: time-division opportunistic (TO) beamforming where in different time slots (of different lengths) the transmitter performs opportunistic beamforming to the users requiring the same rate, and weighted opportunistic (WO) beamforming where the random beams are assigned to those users having the largest weighted SINR. For single antenna systems we also look at the capacity-achieving superposition coding (SC) scheme. In all cases, we determine explicit schedules to guarantee the rate constraints and show that, in the limit of large number of users, the throughput loss compared to the unconstrained throughput (sum-rate capacity) tends to zero. We further provide bounds on the rate of convergence of the sum-rates of these schemes to the sum-rate capacity. Finally, we provide simulation results of the performance of different scheduling schemes considered in the paper.
- Published
- 2008
35. Bit Concatenation Based User Relaying in MIMO Broadcast Channels
- Author
-
Jong Yeol Ryu and Wan Choi
- Subjects
Computer science ,Wireless network ,business.industry ,ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS ,Concatenation ,MIMO ,Data_CODINGANDINFORMATIONTHEORY ,Scheduling (computing) ,Channel capacity ,Computer Science::Networking and Internet Architecture ,Dirty paper coding ,Electrical and Electronic Engineering ,business ,Mimo broadcast channel ,Computer Science::Information Theory ,Computer network - Abstract
A novel user relaying scheme based on bit concatenation is proposed for multiple-input multiple-output (MIMO) broadcast channels. In a broadcasting phase, a part of information for a destination user is concatenated to data for a relaying user and transmitted to the relaying user. The destination user receives the part of information via the relaying user in a relaying phase in addition to the data in the broadcasting phase. An achievable rate region for the proposed scheme is derived and an algorithm to characterize the boundary of the rate region is proposed. Our analysis shows that the proposed user relaying in a MIMO BC expands the achievable rate region for the zero-forcing dirty paper coding (ZF-DPC) in the MIMO BC without relaying. It is also shown that the proposed user relaying scheme always outperforms a superposition coding (SC) based user relaying scheme. Optimal and suboptimal user pair scheduling algorithms are investigated for a two-user MIMO BC and the proposed suboptimal user pair scheduling scheme is shown to approach the optimal scheduling when the relaying channel gain is large.
- Published
- 2012
36. Filter and Nested Lattice Code Design for MIMO Fading Channels with Side-Information
- Author
-
Chung-Pi Lee, Shih-Chun Lin, Pin-Hsun Lin, and Hsuan-Jung Su
- Subjects
Gaussian ,MIMO ,Transmitter ,Data_CODINGANDINFORMATIONTHEORY ,symbols.namesake ,Channel state information ,Electronic engineering ,symbols ,Fading ,Dirty paper coding ,Electrical and Electronic Engineering ,Algorithm ,Computer Science::Information Theory ,Mathematics ,Coding (social sciences) ,Communication channel - Abstract
Linear-assignment Gel'fand-Pinsker coding (LA-GPC) is a coding technique for channels with interference known only at the transmitter, where the known interference is treated as side-information (SI). As a special case of the LA-GPC, dirty paper coding has been shown to be able to achieve the optimal interference-free rate for SI channels with perfect channel state information at the transmitter (CSIT). In the cases where only the channel distribution information at the transmitter (CDIT) is available, LA-GPC also has good (sometimes optimal) performance in a variety of fast and slow fading SI channels. In this letter, we design filters in the nested lattice based coding to make it achieve the same rate performance as the LA-GPC in multiple-input multiple-output (MIMO) channels. Compared with the random Gaussian codebooks used in previous works, our resultant coding schemes have algebraic structures and can be implemented in practical systems. Simulations in slow-fading channels are provided, and near interference-free error performance is obtained. The proposed coding schemes can serve as the fundamental building blocks to achieve the promised rate performance of MIMO Gaussian broadcast channels with CDIT or perfect CSIT.
- Published
- 2011
37. Optimal modulation for known interference
- Author
-
Erik G. Larsson and Mikael Skoglund
- Subjects
Computer science ,Iterative method ,Interference (wave propagation) ,Communications system ,Precoding ,Teknik och teknologier ,dirty paper coding ,joint design ,Electronic engineering ,Demodulation ,Computer Science::Symbolic Computation ,Electrical and Electronic Engineering ,Computer Science::Information Theory ,Mathematics ,Modulation ,business.industry ,Transmitter ,Costa precoding ,interference cancellation ,Transmitter power output ,Single antenna interference cancellation ,Engineering and Technology ,Dirty paper coding ,Telecommunications ,business ,Algorithm - Abstract
We present a symbol-by-symbol approach to the problem of canceling known interference at the transmitter in a communication system. In the envisioned system, the modulator maps an information symbol (taken from a finite alphabet) and an interference symbol (from the complex field) onto a transmitted constellation point. Our scheme is based on joint optimization of a modulator and demodulator, subject to a constraint on the average transmit power. The demodulator picks the information symbol (as a function of the received symbol) that minimizes the average error probability. We emphasize that our focus is on transmission in a single (complex) dimension, and hence the proposed technique is a “modulation” rather than a “coding” scheme. We illustrate that the new scheme outperforms Tomlinson–Harashima precoding, which is a classical but suboptimal solution to the one-dimensional known-interference precoding problem. In our simulations, the new approach is able to perform close to the no-interference bound. ©2009 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.Mikael Skoglund and Erik G. Larsson, Optimal Modulation for Known Interference, 2008, IEEE Transactions on Communications, (56), 11, 1892-1899.http://dx.doi.org/10.1109/TCOMM.2008.060382
- Published
- 2008
38. Precoded Modulo-Precanceling Systems for Simulcasting Analog FM and Digital Data
- Author
-
C.-E.W. Sundberg and Haralabos Papadopoulos
- Subjects
Engineering ,Analog signal ,Analog transmission ,Low IF receiver ,business.industry ,Electronic engineering ,HD Radio ,Dirty paper coding ,Digital signal ,Electrical and Electronic Engineering ,business ,Frequency modulation ,Data transmission - Abstract
We present techniques for simulcasting low-power digital data and analog FM over fading channels. Our methods have strong connections to what are referred to as dirty paper coding techniques in that a low-power digital data signal is modulo-added to the host analog FM signal. Due to the low power levels of the digital data and the suppression capability of analog FM, a standard analog FM receiver can be used to reliably recover the analog audio signal. We develop digital receivers that work reliably over fading channels given imperfect channel state information. Spread- response preceding is exploited to not only provide rate-1 temporal diversity benefits, but also to simplify the design of the modulo-precanceler and the receiver. Our theoretical and simulation-based performance analysis of the digital receivers and our MSE-based analog FM distortion analysis suggest that precoded modulo-precanceling schemes provide substantially higher data rates than existing precanceling strategies at the cost of transmission delay and transmitter and receiver complexity. The systems we present are also readily compatible with conventional channel coding techniques as well as with analog FM postcancelers, which can improve the digital receiver bit-error-rate performance at the expense of receiver complexity.
- Published
- 2008
39. Trellis precoding for MIMO broadcast signaling
- Author
-
Aaron Callard, Amir K. Khandani, and A. Saleh
- Subjects
Minimum mean square error ,MIMO ,Space–time trellis code ,Data_CODINGANDINFORMATIONTHEORY ,Space-division multiple access ,Topology ,Transmitter power output ,Precoding ,Electronic engineering ,Dirty paper coding ,Electrical and Electronic Engineering ,Decoding methods ,Computer Science::Information Theory ,Mathematics - Abstract
Channel inversion, and its minimum mean square error (MMSE) variation, are low complexity methods for space division multiple access (SDMA) in multiple input multiple output broadcast channel (MIMO-BC). As the channel matrix deviates from orthogonal, these methods result in a waste of transmit power. This paper proposes a trellis precoding method (across time and space) to improve the power efficiency. Adopting a 4-state trellis shaping method, the complexity of the proposed method, which is entirely at the transmitter side, is equivalent to the search in a trellis with 4N states where N is the number of transmit antennas. Numerical results are presented showing that the achievable gains, which depend on the channel realization, can be significantly higher than the traditional shaping gain which is limited to 1.53 dB.
- Published
- 2009
40. 3D UAV Trajectory and Communication Design for Simultaneous Uplink and Downlink Transmission
- Author
-
Hua, Meng, Yang, Luxi, Wu, Qingqing, and Swindlehurst, A Lee
- Subjects
Trajectory ,Uplink ,Downlink ,Three-dimensional displays ,Throughput ,Unmanned aerial vehicles ,Optimization ,UAV ,communication design ,IoT ,3D trajectory optimization ,monotonic optimization ,cs.IT ,eess.SP ,math.IT ,Data Format ,Electrical and Electronic Engineering ,Communications Technologies - Abstract
In this paper, we investigate the unmanned aerial vehicle (UAV)-Aided simultaneous uplink and downlink transmission networks, where one UAV acting as a disseminator is connected to multiple access points (AP), and the other UAV acting as a base station (BS) collects data from numerous sensor nodes (SNs). The goal of this paper is to maximize the system throughput by jointly optimizing the 3D UAV trajectory, communication scheduling, and UAV-AP/SN transmit power. We first consider a special case where the UAV-BS and UAV-AP trajectories are pre-determined. Although the resulting problem is an integer and non-convex optimization problem, a globally optimal solution is obtained by applying the polyblock outer approximation (POA) method based on the problem's hidden monotonic structure. Subsequently, for the general case considering the 3D UAV trajectory optimization, an efficient iterative algorithm is proposed to alternately optimize the divided sub-problems based on the successive convex approximation (SCA) technique. Numerical results demonstrate that the proposed design is able to achieve significant system throughput gain over the benchmarks. In addition, the SCA-based method can achieve nearly the same performance as the POA-based method with much lower computational complexity.
- Published
- 2020
41. Space-Time Signal Design for Multilevel Polar Coding in Slow Fading Broadcast Channels
- Author
-
Khoshnevis, H, Marsland, I, Jafarkhani, H, and Yanikomeroglu, H
- Subjects
Slow fading broadcast channel ,space-time signal design ,bit-to-symbol mapping design ,polar codes ,multilevel coding ,cs.IT ,math.IT ,Electrical and Electronic Engineering ,Communications Technologies ,Data Format - Abstract
Slow fading broadcast channels can model a wide range of applications in wireless networks. Due to delay requirements and the unavailability of the channel state information at the transmitter (CSIT), these channels for many applications are non-ergodic. The appropriate measure for designing signals in non-ergodic channels is the outage probability. In this paper, we provide a method to optimize space-time block codes (STBCs) based on the outage probability at moderate SNRs. Multilevel polar coded-modulation is a new class of coded-modulation techniques that benefits from low-complexity decoders and simple rate matching. In this paper, we derive the outage optimality condition for multistage decoding and propose a rule for determining component code rates. We also derive an upper bound on the outage probability of STBCs for designing the set-partitioning-based labeling. Finally, due to the optimality of the outage-minimized STBCs for long codes, we introduce a novel method for the joint optimization of short-to-moderate length polar codes and STBCs.
- Published
- 2019
42. A Digital Telemetry System for Physiological Variables
- Author
-
F. Botsch
- Subjects
Engineering ,Data acquisition ,Paper tape ,business.industry ,Telemetry ,Encoding (memory) ,Electrical and Electronic Engineering ,Interrogation ,business ,Field (computer science) ,Computer hardware ,Digital recording ,Portable telemetry - Abstract
A radio telemetry system is described which satisfies the data acquisition requirements for research in the field of military environmental medicine. The adoption of digital encoding, transmitting, and recording techniques, and the development of a methodology which features serial interrogation by a portable data recording station, have resulted in the construction of a 100-subchannel facility capable of precise measurement and recording of a variety of physiological measurands during field maneuvers. The basic equipment configuration includes a data recording station which generates the time base for interrogation and produces a punched paper tape suitable for direct computer entry and five associated data acquisition stations carried by test subjects performing military tasks in environmental extremes. All units are selfcontained, battery-powered, solid-state packages compatible with standard army load carrying systems.
- Published
- 1966
43. Coded path protection: Efficient conversion of sharing to coding
- Author
-
Avci, SN and Ayanoglu, E
- Subjects
Network restoration ,shared path protection ,diversity coding ,network coding ,integer linear programming ,cs.NI ,Electrical and Electronic Engineering ,Communications Technologies ,Data Format - Abstract
Link failures in wide area networks are common and cause significant data losses. Mesh-based protection schemes offer high capacity efficiency but they are slow and require complex signaling. Additionally, real-time reconfigurations of cross-connects threaten their transmission integrity. On the other hand, there are other schemes that are proactive. Proactivity results in higher restoration speed, lower signaling complexity, and higher transmission integrity. This paper introduces a coding-based proactive protection scheme, named Coded Path Protection (CPP). In CPP, a backup stream of the primary data is encoded with other data streams, resulting in capacity savings. In addition to a systematic approach of building valid coding structures, this paper presents an optimal and simple capacity placement and coding group formation algorithm. The algorithm converts the sharing structure of any solution of a Shared Path Protection (SPP) technique into a coding structure with minimum extra capacity. We conducted quantitative and qualitative comparisons of our technique with SPP and Shared Link Protection (SLP). Simulation results confirm that the CPP is significantly faster than both the SPP and the SLP. It is clearly more capacity efficient than the SLP while it incurs marginal extra capacity beyond that of the SPP. © 1972-2012 IEEE.
- Published
- 2013
44. Model-Driven Deep Learning-Based MIMO-OFDM Detector: Design, Simulation, and Experimental Results
- Author
-
Xingyu Zhou, Jing Zhang, Chen-Wei Syu, Chao-Kai Wen, Jun Zhang, and Shi Jin
- Subjects
Signal Processing (eess.SP) ,FOS: Computer and information sciences ,Information Theory (cs.IT) ,Computer Science - Information Theory ,FOS: Electrical engineering, electronic engineering, information engineering ,Electrical Engineering and Systems Science - Signal Processing ,Electrical and Electronic Engineering ,Computer Science::Information Theory - Abstract
Multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM), a fundamental transmission scheme, promises high throughput and robustness against multipath fading. However, these benefits rely on the efficient detection strategy at the receiver and come at the expense of the extra bandwidth consumed by the cyclic prefix (CP). We use the iterative orthogonal approximate message passing (OAMP) algorithm in this paper as the prototype of the detector because of its remarkable potential for interference suppression. However, OAMP is computationally expensive for the matrix inversion per iteration. We replace the matrix inversion with the conjugate gradient (CG) method to reduce the complexity of OAMP. We further unfold the CG-based OAMP algorithm into a network and tune the critical parameters through deep learning (DL) to enhance detection performance. Simulation results and complexity analysis show that the proposed scheme has significant gain over other iterative detection methods and exhibits comparable performance to the state-of-the-art DL-based detector at a reduced computational cost. Furthermore, we design a highly efficient CP-free MIMO-OFDM receiver architecture to remove the CP overhead. This architecture first eliminates the intersymbol interference by buffering the previously recovered data and then detects the signal using the proposed detector. Numerical experiments demonstrate that the designed receiver offers a higher spectral efficiency than traditional receivers. Finally, over-the-air tests verify the effectiveness and robustness of the proposed scheme in realistic environments., 31 pages, 13 figures, 4 tables. This paper has been accepted for publication by the IEEE Transactions on Communications. The code is available at https://github.com/STARainZ/CG-OAMP-NET
- Published
- 2022
45. Rate-Adaptive Concatenated Multi-Level Coding With Novel Probabilistic Amplitude Shaping
- Author
-
Toshiki Matsumine, Metodi Plamenov Yankov, Tayyab Mehmood, and Soren Forchhammer
- Subjects
Modulation ,Decoding ,Complexity theory ,Encoding ,Forward error correction ,Data_CODINGANDINFORMATIONTHEORY ,Electrical and Electronic Engineering ,Reliability ,Codes - Abstract
This paper proposes a new probabilistic amplitude shaping (PAS) approach for concatenated two-level multi-level coding (MLC). The proposed system is based on a concatenated forward error correction (FEC) scheme where outer codes are serially concatenated with inner two-level MLC. This concatenated two-level MLC scheme has recently been shown to have a potential for achieving better performance-complexity trade-offs than the conventional bit-interleaved coded modulation (BICM). Meanwhile, PAS has recently been demonstrated to offer remarkable performance gains as well as rate adaptivity. However, the majority of existing works on PAS assume the use of the binary reflected Gray code as a bit-labeling, and its application to coded modulation schemes with other bit-labelings, such as two-level MLC, may not be straightforward. In this paper, we devise a bit-labeling scheme and propose a new PAS structure for an efficient integration of PAS with two-level MLC systems. More specifically, we propose to generate signed amplitude symbols with the distribution matcher (DM) for maximizing both coding and shaping gains achieved by two-level MLC and PAS, respectively, while the conventional PAS generates unsigned amplitude symbols. It is demonstrated by simulation results that, with 256QAM and inner polar codes, the proposed two-level MLC with PAS simultaneously offers 75% reduction in the number of required inner encoding and soft-decision (SD) decoding operations for given outer and inner FEC code lengths, and up to 0.3 dB performance gain over the conventional PAS scheme.
- Published
- 2022
46. Capacity Characterization for Reconfigurable Intelligent Surfaces Assisted Wireless Communications With Interferer
- Author
-
Linsong Du, Jianhui Ma, Qingpeng Liang, Youxi Tang, and Chenxing Li
- Subjects
Computer science ,business.industry ,ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS ,Transmitter ,Boundary (topology) ,Maximization ,Signal ,Channel capacity ,Interference (communication) ,Electronic engineering ,Wireless ,Electrical and Electronic Engineering ,business ,Computer Science::Information Theory ,Communication channel - Abstract
The reconfigurable intelligent surface (RIS), which consists of many low-cost reflecting elements, can enhance the reception of the desired signal and suppress the interference. Considering the above advantages, this paper investigates the RIS-assisted wireless communication in the presence of an interferer, where a receiver receives the desired signal and interference from a transmitter and an interferer, respectively, and the RIS is deployed to assist this system. First, an interference-limited channel capacity maximization problem is formulated, and a numerical algorithm based on the fraction programming and optimality conditions is proposed to obtain the optimal solution. Then, this paper shows the upper boundary of the maximal capacity with interference and discusses what kind of channel conditions can achieve the upper boundary and the corresponding optimal phase shifts. Next, this paper analyzes the asymptotic behaviors of the maximal capacity in the scenarios that some or all of the number of reflecting elements, antennas at the transmitter, and interferer go to infinity. Finally, this paper generalizes the above results to the multiple interferers scenario.
- Published
- 2022
47. Power Allocation for Uplink Multi-User Optical Wireless Communication Systems
- Author
-
Prashant Narayanan, Lakshmi Narasimhan Theagarajan, and Steve Hranilovic
- Subjects
Computer science ,Computation ,Distributed computing ,Telecommunications link ,Key (cryptography) ,Optical wireless ,Maximization ,Electrical and Electronic Engineering ,Multi-user ,Communications system ,Power (physics) - Abstract
Indoor optical wireless communication (IOWC) is a key technology complementing radio communication in 6G. Typically, the downlink of IOWC is implemented using visible light and uplink is implemented using infrared. Though the downlink of IOWC has been studied well, the uplink of multiple-access IOWC requires further research. In this paper, power allocation strategies in the uplink of IOWC with multiple non-cooperative users is studied. Optimizing power allocation in IOWC that maximize sum-rate with power constraints becomes a non-convex problem. First, this paper proposes an alternating maximization algorithm to compute near optimal power allocation policies for small number of users. Next, a phenomenon of invariance is observed when the number of users in the system is large. Under invariance, the optimal power allocation policy of a user becomes independent of other users, thereby facilitating fast and decentralized computation of power allocation strategies. From simulations, it was observed that the invariance can occur even with five to ten users. For the first time, a rigorous analysis of the invariance phenomenon is provided. An algorithm to compute the optimal power allocation at invariance is proposed; this algorithm is proven to achieve the global maxima in sum-rate without the channel knowledge of other users.
- Published
- 2022
48. Efficient NOMA Design Without Channel Phase Information Using Amplitude-Coherent Detection
- Author
-
Mohamed-Slim Alouini, Ki-Hong Park, Mohammad A. Al-Jarrah, Youssef Iraqi, Arafat Al-Dweik, and Emad Alsusa
- Subjects
Computer science ,amplitude shift keying (ASK) ,Equalization (audio) ,Silicon carbide ,Interference (wave propagation) ,Receivers ,phase estimation ,Noma ,non-coherent detection ,medicine ,Wireless ,multiple access ,Electrical and Electronic Engineering ,Computer Science::Information Theory ,Modulation ,business.industry ,Complexity theory ,Detector ,channel estimation ,NOMA ,amplitude coherent ,Detectors ,medicine.disease ,Single antenna interference cancellation ,Bit error rate ,Non-orthogonal multiple access (NOMA) ,business ,Algorithm ,Communication channel - Abstract
This paper presents the design and bit error rate (BER) analysis of a phase-independent non-orthogonalmultiple access (NOMA) system. The proposed NOMA system can utilize amplitude-coherent detection(ACD) which requires only the channel amplitude for equalization purposes. In what follows, threedifferent designs for realizing the detection of the proposed NOMA are investigated. One is based on themaximum likelihood (ML) principle, while the other two are based on successive interference cancellation(SIC). Closed-form expressions for the BER of all detectors are derived and compared with the BER ofthe coherent ML detector. The obtained results, which are corroborated by simulations, demonstrate that,in most scenarios, the BER is dominated by multiuser interference rather than the absence of the channelphase information. Consequently, the BER using ML and ACD are comparable for various cases ofinterest. The paper also shows that the SIC detector is just an alternative approach to realize the MLdetector, and hence, both detectors provide the same BER performance.
- Published
- 2022
49. Intelligent Reflecting Surface-Aided URLLC in a Factory Automation Scenario
- Author
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Kezhi Wang, Hong Ren, and Cunhua Pan
- Subjects
Networking and Internet Architecture (cs.NI) ,FOS: Computer and information sciences ,intelligent reflecting surface (IRS) ,G500 ,Computer science ,G400 ,Reliability (computer networking) ,Quality of service ,short-packet transmission ,G900 ,Nakagami distribution ,Data_CODINGANDINFORMATIONTHEORY ,Computer Science - Networking and Internet Architecture ,Transmission (telecommunications) ,Rician fading ,Electronic engineering ,reconfigurable intelligent surface (RIS) ,Fading ,Electrical and Electronic Engineering ,URLLC ,Communication channel ,Rayleigh fading - Abstract
Different from conventional wired line connections, industrial control through wireless transmission is widely regarded as a promising solution due to its reduced cost, increased long-term reliability, and enhanced reliability. However, mission-critical applications impose stringent quality of service (QoS) requirements that entail ultra-reliability low-latency communications (URLLC). The primary feature of URLLC is that the blocklength of channel codes is short, and the conventional Shannon's Capacity is not applicable. In this paper, we consider the URLLC in a factory automation (FA) scenario. Due to densely deployed equipment in FA, wireless signal are easily blocked by the obstacles. To address this issue, we propose to deploy intelligent reflecting surface (IRS) to create an alternative transmission link, which can enhance the transmission reliability. In this paper, we focus on the performance analysis for IRS-aided URLLC-enabled communications in a FA scenario. Both the average data rate (ADR) and the average decoding error probability (ADEP) are derived under finite channel blocklength for seven cases: 1) Rayleigh fading channel; 2) With direct channel link; 3) Nakagami-m fading channel; 4) Imperfect phase alignment; 5) Multiple-IRS case; 6) Rician fading channel; 7) Correlated channels. Extensive numerical results are provided to verify the accuracy of our derived results., Comment: Accepted by IEEE TCOM
- Published
- 2022
50. RIS-Aided Wireless Communications: Prototyping, Adaptive Beamforming, and Indoor/Outdoor Field Trials
- Author
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Haifan Yin, Li Tan, Kai Wang, Kun Zhang, Lin Cao, Emil Björnson, Zhanpeng Li, and Xilong Pei
- Subjects
Signal Processing (eess.SP) ,FOS: Computer and information sciences ,Power gain ,Data stream ,business.industry ,Computer science ,Computer Science - Information Theory ,Information Theory (cs.IT) ,Transmitter ,1080p ,Field (computer science) ,FOS: Electrical engineering, electronic engineering, information engineering ,Electronic engineering ,Wireless ,Indoor outdoor ,Electrical Engineering and Systems Science - Signal Processing ,Electrical and Electronic Engineering ,business ,Adaptive beamformer - Abstract
The prospects of using a Reconfigurable Intelligent Surface (RIS) to aid wireless communication systems have recently received much attention from academia and industry. Most papers make theoretical studies based on elementary models, while the prototyping of RIS-aided wireless communication and real-world field trials are scarce. In this paper, we describe a new RIS prototype consisting of 1100 controllable elements working at 5.8 GHz band. We propose an efficient algorithm for configuring the RIS over the air by exploiting the geometrical array properties and a practical receiver-RIS feedback link. In our indoor test, where the transmitter and receiver are separated by a 30 cm thick concrete wall, our RIS prototype provides a 26 dB power gain compared to the baseline case where the RIS is replaced by a copper plate. A 27 dB power gain was observed in the short-distance outdoor measurement. We also carried out long-distance measurements and successfully transmitted a 32 Mbps data stream over 500 m. A 1080p video was live-streamed and it only played smoothly when the RIS was utilized. The power consumption of the RIS is around 1 W. Our paper is vivid proof that the RIS is a very promising technology for future wireless communications., Comment: 13 pages, 18 figures, submitted
- Published
- 2021
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