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Space-division multiplexing (SDM) in few-mode multi-core fibers (FM-MCF) allows the transmission of multi-petabit/s data-rates over a single optical fiber. Recently, transmission of more than 1.2 Pbit/s was demonstrated in a FM-MCF with a cladding diameter of 160 μm, compatible with the standard coating diameter of 250 μm [1]. When increasing the core density in FM-MCF or the transmission distance, inter-core crosstalk can limit the achievable data rates. Inter-core crosstalk is strongly wavelength-dependent and higher-order modes in FM-MCF are expected to show a larger crosstalk penalty compared to the fundamental mode, as their mode fields extend farther into the cladding [2]. In this paper, we present an experimental investigation of the crosstalk-induced Q-factor degradation of 16-Quadrature amplitude modulation (16-QAM) signals, transmitted over a four-core three-mode fiber Refereed/Peer-reviewed

We experimentally demonstrate a 28-Gbaud 16-QAM self-homodyne digital radio-over- 33.6km-7-core-fiber system with entropy coding for mobile fronthaul, achieving error-free carrier aggregation of 330 100-MHz 4096-QAM 5G-new-radio channels and 921 100-MHz QPSK 5G-new-radio channels with CPRI-equivalent data rate up to 3.73-Tbit/s., Comment: 3 pages, 44th European Conference on Optical Communication (ECOC 2018), Rome, Italy, 2018

We address in this paper the challenge of coping with asymmetric data rates in two-way relay channels. We consider a relay network comprising two sources and one relay. The sources communicate at different rates through the relay. That is, we assume that one source uses M 1 -QAM (quadrature amplitude modulation) and the other uses M 1 /M 2 -QAM hierarchical modulation where M 1 ≠ M 2 . For the underlying network, we consider two decode-and-forward (DF) relaying schemes. One scheme combines hierarchical zero padding and network coding (HZPNC) at the relay. The novelty of this scheme lies in the way the two signals (that have different lengths) are network-coded at the relay. The other scheme is referred to as opportunistic user selection (OUS) where the user with a better end-to-end channel quality is given priority for transmission. We analyze both schemes where we derive closedform expressions for the end-to-end (E2E) bit error rate (BER). Since the two schemes offer a trade-off between performance and throughput, we analyze and compare both schemes in terms of channel access probability and average throughput. We show that HZPNC offers better throughput and fairness for both users, whereas OUS offers better performance. We also compare the performance of HZPNC with existing schemes including the original zero padding, nesting constellation modulation and superposition modulation. We show through examples the superiority of the proposed HZPNC scheme in terms of performance and/or reduced complexity. Scopus

In this paper we present two resource allocations techniques in a visible light communication network with overlapping coverage areas due to the use of access points. Particularly, the first approach exploits the rate maximization criteria, and then aims at maximizing the network rate under constraints on minimum and maximum rates, while the other procedure focuses on achieving fairness in the rate of each user accessing the network. The proposed system relays on optical code division multiple access mechanism, and resource allocation is intended in terms of codes assigned to a given user. Simulation results have been addressed in terms of achievable data rates, outage probability and percentage of accessing users.

Komunikacija putem vidljive svjetlosti ili VLC je optička bežična komunikacija koja koristi valove vidljivog spektra (380 nm do 780 nm) za prijenos informacija. To je komunikacijska tehnologija kratkog dometa, a za konfiguraciju linka se koristi izvor vidljivog svjetla (LED) kao odašiljač signala, zrak kao prijenosni medij i fotodioda kao prijemnik. Obzirom na svrhu, razlikujemo VLC velike brzine prijenosa podataka (engl. High Data Rate, HDR) i VLC male brzine prijenosa podataka (engl. Low Data Rate, LDR). HDR je kompleksniji za implementaciju i zahtjeva modificiranje postojeće infrastrukture, dok je LDR ostvariv s današnjim hardverom u mobilnim uređajima. Potencijalni oblici primjene VLC tehnologije su precizno unutarnje pozicioniranje (VLP), Li-Fi, V2V komunikacija i primjena u područjima osjetljivim na elektromagnetsko (EM) i RF zračenje. Brojne korporacije, organizacije i sveučilišta diljem svijeta rade na razvoju i standardizaciji VLC tehnologije, kao što VLCC, IEEE, Li-Fi konzorcij, PureLiFi, Twibrigth Labs i drugi. VLCC je predložio dva JEITA standarda, dok je IEEE osnovao VLC grupu 802.15.7 koja je definirala MAC i PHY slojeve. Ujedno je definirala odgovarajuće LED modulacijske metode, poput IM/DM, OOK, VPPM i CSK. VLC komercijalizacija je još uvijek u ranoj fazi razvoja, a ovisi o pažljivom planiranju, postupnom plasiranju rješenja na tržište i suradnji između različitih industrija. PureLiFi je već iznio svoja rješenja za VLC komunikaciju, no potreban je dodatni razvoj i komercijalizacija kompatibilnih LED žarulja da bi ideja „Pametna svjetla“ zaživjela. Uz trenutno sveprisutnu RF komunikaciju, VLC je prvenstveno osmišljen kao dodatni komunikacijski sloj koji bi omogućavao bežični podatkovni link gdje radio transmisija nije moguća, željena ili dovoljna. Visible light communication or VLC is an optical wireless communication using waves of the visible spectrum (380 nm to 780 nm) for the transmission of information. It is a short-range communication technology and source of visible light (LED) as a transmitter signal, air as a transmission medium and a photodiode as a receiver are used for link configuration. Considering the purpose, we distinguish high-data-rate (HDR) and low-data-rate (LDR) VLC. HDR is more complex to implement and requires same modifications of the existing infrastructure, while LDR is achievable with existing hardware in mobile devices. Potential applications of VLC technology are accurate indoor positioning (VLP), Li-Fi, V2V communication and application in areas sensitive to EM and RF radiation. Numerous corporations, organizations and universities around the world have been working on the development and standardization of VLC technology, such as VLCC, IEEE, Li-Fi Consortium, PureLiFi, Twibrigth Labs and others. VLCC has proposed two JEITA standards, while the IEEE founded VLC group called 802.15.7 which defined MAC and PHY layers. They also defined LED modulation methods, such as IM / DM, OOK, VPPM and CSK. VLC commercialization is still in the early stage of development and it depends on careful planning, gradual introducing of solutions to the market and cooperation between different industries. PureLiFi has already presented their solutions for VLC but additional development and commercialization of compatible LED bulbs may be required before the "Smart lighting" concept can be applied in practice. With the currently omnipresent RF communication, VLC is primarily suitable as an additional communication layer that will enable wireless data link where radio transmission is not possible, desirable or enough.

A new generation of information and communication technologies (ICTs) is finding a small foothold among poor, small-scale farmers in developing countries. Even so, many barriers still prevent poor rural people from accessing, using, and benefiting from new ICT tools and platforms, and those barriers are arguably higher for rural women. The relationship between gender and agriculture has been studied intensively over the years, and many agricultural interventions now include gender as a crosscutting issue or mainstream gender throughout their operations. Studies of the relationship between gender and the use of ICTs in agriculture have started to appear only quite recently, however. The Africa Region of the World Bank views ICTs as potentially transformative technology for rural development and seeks to incorporate the use of ICTs throughout its portfolio of projects. The present study was designed to examine the feasibility of integrating ICTs into two large investment programs: the Irrigation Development and Support Project (IDSP) in Zambia and the Kenya Agricultural Productivity and Agribusiness Project (KAPAP). The specifi c goal was to examine how ICT-based interventions might be designed to strengthen women s participation in commodity value chains under the two projects.

A large-signal analysis is presented for a DC-biased Fabry-Perot laser locked by simultaneous strong optical injection of a CW signal and a modulated signal into different modes. The model is based on the description of injection-locking by Lang (1982) which is shown to hold even under the condition of strong injection and large detuning of the input signals. The following results are obtained: the configuration allows all-optical wavelength conversion in the multigigabit range, and both logically noninverting and inverting conversion is possible. In both operation modes, the conversion mechanism is mainly attributed to dispersive switching which is shown to be very fast above threshold due to injection-locking. Operation up to data rates of 20 Gb/s is possible with reasonable output extinction ratio. The bandwidth is determined by the relaxation oscillation frequency of the laser. It will be extended by decreasing the resonator length, increasing the injected current, and increasing the injected optical power. The output signal is nearly chirp-free. The model is able to explain the main results of previously published experiments.

To accommodate the ever increasing wireless traffic in the access networks, considerable efforts have been recently invested in developing photonics-assisted wireless communication systems with very high data rates. Superior to photonic millimeter-wave systems, terahertz (THz) band (300 GHz-10 THz) provides a much larger bandwidth and thus promises an extremely high capacity. However, the capacity potential of THz wireless systems has by no means been achieved yet. Here, we successfully demonstrate 160 Gbit/s wireless transmission by using a single THz emitter and modulating 25 GHz spaced 8 channels (20 Gbps per channel) in the 300-500 GHz band, which is the highest bitrate in the frequency band above 300 GHz, to the best of our knowledge.

The dynamic growth of mobile communications technology is creating opportunities for economic growth, social empowerment, and grassroots innovation in developing countries. One of the areas with the greatest potential impact is in the contribution that mobile applications can make to agricultural and rural development (ARD), by providing access to information, markets, and services to millions of rural inhabitants. For both agricultural supply and demand, mobile phones can reduce waste, make delivery more efficient, and forge closer links between farmers and consumers. This report provides policymakers and development practitioners with a guide that facilitates the development and deployment of mobile applications for ARD. It also informs their understanding of the key drivers for promoting such applications and services in their countries. Using James Moore’s (1996) revised definition of ecosystems: economic communities based on interacting organizations and individuals the report identifies a wide range of players in the ecosystem for m-ARD apps, such as mobile network operators, m-app (mobile applications) providers, content providers, and various types of users. M-apps are software designed to take advantage of mobile technology and can be developed for technology besides mobile phones. But mobile phones have many key advantages: affordability, wide ownership, voice communications, and instant and convenient service delivery. As a result, there has been a global explosion in the number of m-apps, facilitated by the rapid evolution of mobile networks and by the increasing functions and falling prices of mobile handsets. M-apps are markedly different in developing countries because they typically run on second-generation (2G) phones rather than smartphones, which are far more common in developed countries. The report reviews country examples and extracts policy lessons and good practices. It also presents detailed studies of cases from Kenya, Philippines, and Sri Lanka, as well as summarizes 92 case studies from Africa, Asia, and Latin America. The goal is to provide a comprehensive understanding of the development impact, ecosystem, and business models for mobile applications in ARD. The report is intended to complement the recent ICT in Agriculture eSourcebook. One of the main findings is that an enabling platform (or platforms) is probably the most important factor for the development of m-ARD apps. Platforms can facilitate interactions among ecosystem players, increase access to users, provide technical standards, and incorporate payment mechanisms.

Cooperative communication is shown to be an efficient method of combating fading in wireless networks. By "sharing" their antennas cooperating single-antenna nodes create a virtual multi-antenna system and therefore, benefit from spatial diversity. Network coding being a particular cooperative communication technique provides substantial gains in data rate, especially in networks with many sink nodes. By allowing intermediate nodes of a network to mix the incoming data streams, one can achieve the multicast capacity. Recently, Xiao and Skoglund showed that binary network coding (BNC) is not optimal for multi-user multi-relay networks in terms of diversity and proposed diversity network coding (DNC) scheme that outperforms BNC approach. Following this approach we examine potential diversity gains of using the DNC scheme for multi-source line networks. We show that the DNC technique outperforms both conventional time-orthogonal transmission and the BNC scheme. Further, the problem of optimal scheduling of the transmission is explored. We formulate the optimization problem and propose efficient solutions. Numerical results are presented to support theoretical findings. Refereed/Peer-reviewed

In this paper, we investigate the effects of asymmetric frequency-dependent joint transmit-receive I/Q imbalance on the performance of multiple beamforming MIMO OFDM systems. We derive the throughput-maximizing TX/RX beamforming coefficients taking into account I/Q imbalance effects. In addition, we propose a low-complexity pilot-aided scheme for the estimation of the channel and I/Q imbalance parameters. Our simulation results demonstrate that the proposed generalized multiple beamforming scheme is effective in mitigating I/Q imbalance effects and by using multiple beamforming data rate can be increased at the expense of increased error rate. 2012 IEEE. Scopus

Fourth-generation cellular mobile wireless broadband systems are currently being trialled and deployed in Australia and around the world. This next generation is driven by increasing customer demand for ubiquitous access and higher data rates, the opportunity for increased revenues and lower costs for network operators, and the pursuit of more efficient, harmonised and profitable spectrum by regulators. Focusing on the 3GPP evolution path, we present an overview of technologies for 4G and beyond, and consider the opportunities in Australia in terms of spectrum, future wireless networks, and the National Broadband Network. Refereed/Peer-reviewed

Modern communication systems require higher data rates which have increased thedemand for high speed transceivers. For a system to work efficiently, all blocks ofthat system should be fast. It can be seen that analog interfaces are the main bottleneckin whole system in terms of speed and power. This fact has led researchersto develop high speed analog to digital converters (ADCs) with low power consumption.Among all the ADCs, flash ADC is the best choice for faster data conversion becauseof its parallel structure. This thesis work describes the design of such a highspeed and low power flash ADC for analog front end (AFE) of a transceiver. Ahigh speed highly linear track and hold (TnH) circuit is needed in front of ADCwhich gives a stable signal at the input of ADC for accurate conversion. Twodifferent track and hold architectures are implemented, one is bootstrap TnH andother is switched source follower TnH. Simulations show that high speed with highlinearity can be achieved from bootstrap TnH circuit which is selected for the ADCdesign.Averaging technique is employed in the preamplifier array of ADC to reduce thestatic offsets of preamplifiers. The averaging technique can be made more efficientby using the smaller number of amplifiers. This can be done by using the interpolationtechnique which reduces the number of amplifiers at the input of ADC. Thereduced number of amplifiers is also advantageous for getting higher bandwidthsince the input capacitance at the first stage of preamplifier array is reduced.The flash ADC is designed and implemented in 150 nm CMOS technology for thesampling rate of 1.6 GSamples/sec. The bootstrap TnH consumes power of 27.95mW from a 1.8 V supply and achieves the signal to noise and distortion ratio(SNDR) of 37.38 dB for an input signal frequency of 195.3 MHz. The ADC withideal TnH and comparator consumes power of 78.2 mW and achieves 4.8 effectivenumber of bits (ENOB).

Date of Conference: 18-20 April 2012 Ultra-Wideband (UWB) communication systems have been developed for short distance, high data rate communications. To avoid interfering with the existing systems in the same environment, very short duration pulses used by these systems should satisfy a predefined spectral mask. Data rate of UWB systems can be increased by using multiple pulse shapes simultaneously. Orthogonality of the simultaneously used pulse shapes simplifies the receiver design. In this work, design of orthogonal pulse shapes which satisfy the spectral mask is modelled as an optimization problem. First, it is converted to a convex optimization problem by constraining the pulse shapes to lie in a subspace spanned by the Hermite-Gaussian (HG) functions. Then the optimal solution is obtained. It is shown that a larger pulse shape set can be designed compared to the existing approaches, and hence, a higher data rate can be achieved. © 2012 IEEE.

To optimize performance of ad hoc networks, the contradicting objectives: energy conservation and high data rate realization need to be jointly considered. In such a case, network interference need to be controlled in a manner that users transmit at minimum power enough to sustain the transmission. This paper proposes a joint power and rate adaptation in ad hoc network based on coupled interference minimization (PRIM) where the formulated network utility maximization (NUM) is solved using reverse engineering based on Karush-Kuhn-Tucker (KKT) conditions. In that way, users determine their transmit power and data rate based on their local observations (coupled interference). Pricing mechanism is employed in PRIM to restrict users from self-interest behaviours. It is demonstrated theoretically that PRIM satisfies the conditions of the super-modular games such that the local optimality is always the global optimality. Simulation results have shown that adapting transmits power and data rates based on the coupled interference (i.e. link dynamics) can improve the performance of ad hoc networks.

The wide range of wireless body area network (WBAN) applications gives rise to different system requirements for the carrier frequencies and data rates. In order to accommodate various standards in WBAN applications, a universal receiver system with good performance and low power is highly desirable. The subsampling receiver architecture is one of the promising receiver architectures that might fulfill the features of low power consumption and reconfigurability. However, there are two main concerns, namely the frequency stability and noise performance. In order to overcome these problems, a novel subsampling receiver architecture with two sampling branches as well as a new compensation algorithm are proposed and analyzed in this paper. The frequency stability and noise performance of the receivers can be greatly improved using this architecture. Simulation in different scenarios is carried out, and the results verify the effectiveness of the proposed architecture. © 2011 IEEE.

The wide range of wireless body area network (WBAN) applications gives rise to different system requirements for the carrier frequencies and data rates. In order to accommodate various standards in WBAN applications, a universal receiver system with good performance and low power is highly desirable. The subsampling receiver architecture is one of the promising receiver architectures that might fulfill the features of low power consumption and reconfigurability. However, there are two main concerns, namely the frequency stability and noise performance. In order to overcome these problems, a novel subsampling receiver architecture with two sampling branches as well as a new compensation algorithm are proposed and analyzed in this paper. The frequency stability and noise performance of the receivers can be greatly improved using this architecture. Simulation in different scenarios is carried out, and the results verify the effectiveness of the proposed architecture. © 2011 IEEE.

As the CMOS semiconductor technology enters nanometer regime, interconnect processes must be compatible with device roadmaps and meet manufacturing targets at the specified wafer size. The resulting ubiquitous process variations cause errors in data delivering through interconnects. This paper proposes an Information Theory based design method to accommodate process variations. Different from the traditional delay based design metric, the current approach uses achievable rate to relate interconnect designs directly to communication applications. More specifically, the data communication over a typical interconnect, a bus, subject to process variations (uncertain bus), is defined as a communication problem under uncertainty. A data rate, called the achievable rate, is computed for such a bus, which represents the lower bound on the maximal data rate attainable over the bus. When a data rate applied over the bus is smaller than the achievable data rate, a reliable communication can be guaranteed regardless of process variations, i.e., a bit error rate arbitrarily close to zero is achievable. A single communication strategy to combat the process variations is proposed whose code rate is equal to the computed achievable rate. The simulations show that the variations in the interconnect resistivity could have the most harmful effect regarding the achievable rate reduction. Also, the simulations illustrate the importance of taking into account bus parasitic parameters correlations when measuring the influence of the process variations on the achievable rates. © 2006 IEEE. 19 3 397 410

In this chapter, fully integrated organic RFID tags are demonstrated. These tags are inductively-coupled at a base frequency of 13.56 MHz and can be read out at distances up to 10 cm, which is the expected readout distance for proximity readers. We also demonstrate next generation transponder chips, fabricated in a dual-gate technology. The additional gate, backgate, is used to control the threshold voltage and allows integration into more robust unipolar, dual-VT transponder chips. Finally, we realized an 8-bit transponder chip having data rates that are EPC-compatible. This has been achieved in our thin-film transistor technology by introducing a high-k Al2O 3 gate dielectric, by scaling the channel lengths down to 2 mm and by reducing the overlap capacitance of the parasitic source-gate and drain-gate capacitors. © 2011 Springer Science+Business Media B.V.

In this chapter, fully integrated organic RFID tags are demonstrated. These tags are inductively-coupled at a base frequency of 13.56 MHz and can be read out at distances up to 10 cm, which is the expected readout distance for proximity readers. We also demonstrate next generation transponder chips, fabricated in a dual-gate technology. The additional gate, backgate, is used to control the threshold voltage and allows integration into more robust unipolar, dual-VT transponder chips. Finally, we realized an 8-bit transponder chip having data rates that are EPC-compatible. This has been achieved in our thin-film transistor technology by introducing a high-k Al2O 3 gate dielectric, by scaling the channel lengths down to 2 mm and by reducing the overlap capacitance of the parasitic source-gate and drain-gate capacitors. © 2011 Springer Science+Business Media B.V.

Dual-gate organic transistor technology is used to increase the robustness of digital circuits as illustrated by higher inverter gains and noise margins. The additional gate in the technology functions as a V-T-control gate. Both zero-V-GS-load and diode-load logic are investigated. The noise margin of zero-V-GS-load inverter increases from 1.15 V (single gate) to 2.8 V (dual gate) at 20 V supply voltage. Diode-load logic inverters show an improvement in noise margin from similar to 0 V to 0.7 V for single gate and dual gate inverters, respectively. These values can be increased significantly by optimizing the inverter topologies. As a result of this optimization, noise margins larger than 6 V for zero-V-GS-load logic and 1.4 V for diode-load logic are obtained. Functional 99-stage ring oscillators with 2.27 mu s stage delays and 64 bit organic RFID transponder chips, operating at a data rate of 4.3 kb/s, have been manufactured. ispartof: pages:1223-1230 ispartof: IEEE Journal of Solid-State Circuits vol:46 issue:5 pages:1223-1230 ispartof: location:CA, Anaheim status: published

We investigate an outage optimal adaptive resource allocation scheme for the upstream of two-hop OFDMA based decode-and-forward cooperative relay systems. The objective of this work is to design resource allocation strategy, which addresses the needs of the users minimizing their outage probability. This scheme utilizes the subchannel-pairing and proportional fairness in two-hop multiuser multirelay network to achieve the user required percentage throughput ( i.e., if the user's application can tolerate 5% outage then guaranteeing the 100% availability is actually a wastage of scarce radio resources). Using outage optimal resource allocation scheme, we achieve the complimentary fairness along with the required data rate on each node. Simulation results show that the proposed scheme achieve better throughput-fairness trade-off compared to proportional fair scheduling (PFS) and MaxMin resource allocation schemes. 2011 IEEE. Scopus

Dual-gate organic transistor technology is used to increase the robustness of digital circuits as illustrated by higher inverter gains and noise margins. The additional gate in the technology functions as a VT-control gate. Both zero-VGS-load and diode-load logic are investigated. The noise margin of zero- VGS-load inverter increases from 1.15 V (single gate) to 2.8 V (dual gate) at 20 V supply voltage. Diode-load logic inverters show an improvement in noise margin from ~0 V to 0.7 V for single gate and dual gate inverters, respectively. These values can be increased significantly by optimizing the inverter topologies. As a result of this optimization, noise margins larger than 6 V for zero- V GS-load logic and 1.4 V for diode-load logic are obtained. Functional 99-stage ring oscillators with 2.27 µs stage delays and 64 bit organic RFID transponder chips, operating at a data rate of 4.3 kb/s, have been manufactured.

During the last few years, several authors have studied the performance of many different types of channel codes for cooperative communication systems. Some of these codes include Low Density Parity Check (LDPC), Turbo and convolutional codes. Published results show that these codes effectively improve both the data rate and system performance in cooperative schemes such as the decode and forward (DF). Reed-Solomon (RS) codes are one of the most widely used channel codes in wireless communication systems today. These codes have also been adopted by several 3G standards including several digital video broadcasting (DVB) standards and also by worldwide interoperability for microwave access (WiMAX) which is based on the IEEE 802.16 standard. However, published literature shows no specific study to investigate their performance for the cooperative communication environment. Using the component codes adopted in the IEEE 802.16 standard, this paper investigates the performance of the concatenated RS coding schemes for cooperative communication. This paper first analyses the standard RS-coded DF cooperative system. The results obtained for the standard RS-coded scheme show huge gains over the non-cooperative system. Some of the problems of the standard DF relay protocol is then discussed and an improved RS-coded DF cooperative scheme is proposed. The performance of the proposed scheme shows significant gains over the standard RS-coded DF system. Qatar National Research Fund Scopus

We propose a data precoded relay-assisted scheme, for a system cooperating with L relays, each one equipped with a single antenna. The use of relays is of significant interest to allow radio access in situations where either the direct path is not available or has poor quality. However because of the half duplex constraint at the relays, transmission of a data rate that would be possible using a modulation technique with m bits per symbol in the case a continuous link was available from the BS to the UT, requires the use of a constellation with 2m bits per symbol. This implies a penalty in the power efficiency. In this communication we propose a simple precoding scheme that exploits the relation between QPSK and 4L-QAM, by alternately transmitting through the L relays, keeping the diversity of order L. Numerical results are presented for the case where 2 relay nodes are used, for realistic scenarios with LTE parameters and using turbo coding, showing significant performance improvements relatively to the case of a relay based distributed Alamouti employing 16-QAM. ©2010 IEEE. European project CODIV - FP7-ICT-2007-215477 CADWIN - PTDC/EEATEL/ 099241/2008 Portuguese Foundation for Science and Technology (FCT) grant

This article attempts to improve the average efficiency and linearize the work-horse of RF power amplification- the class-B (or class AB) PA-relying, for example, on predistortion, dynamic load modulation or ET. Nevertheless, whenever higher efficiencies are desired, the current-mode class-B PA must be replaced by switchedmode PAs (for example, class-E or class-F), completely modifying the paradigm of RF amplification. In fact, as these are saturated circuits, they cannot respond to excitations of variable amplitude; and thus the original signal envelope must be restored by operating the PA as an AM modulator via dynamic supply adaptation. A good example of this is the EER arrangement.

Multiview video is increasingly getting attention due to emerging applications such as 3DTV and immersive teleconferencing. In this paper, we present a non-stationary Hidden Markov Model (HMM) for characterizing the data rate of compressed multiview content. The states of the model correspond to different video activity levels and exhibit a Poisson state duration distribution. We derive a stable maximum likelihood algorithm for estimating the parameters of our multiview traffic model. Synthetic data generated by the model exhibits statistics that closely match those of actual multiview data. In addition, we demonstrate the high accuracy of the model in two multiview streaming applications by evaluating the frame loss rate of a constrained network buffer fed by actual and synthetic data.

Conference name: IEEE 17th Signal Processing and Communications Applications Conference, SIU 2009 Date of Conference: 9-11 April 2009 Gelecek nesil kablosuz iletişim sistemlerinde öngörülen veri hızlarına ulaşabilmek için bu sistemlerde frekans yeniden kullanım oranının 1 olmasına ihtiyaç¸ vardır, bu ise özellikle hücre sınırlarındaki kullanıcıların önemli ölçüde hücreler arası girişime maruz kalmalarına neden olur. Telsiz erişim terminalleri arasında işbirliği hücreler arası girişimin azaltılmasında önemli bir rol oynamaktadır. Bu bildiride çok hücreli, çok girdili çok çıktılı, dikgen frekans bölmeli çoklu erişim sistemlerinde telsiz erişim terminallerinden kullanıcılara işbirlikli veri iletimi problemini ele alıyoruz. Telsiz erişim terminallerinin aralarında kısıtlı ileti paylaşımı ile çizelgeleme ve veri iletimi yaptıkları etkin bir işbirlikli algoritma öneriyoruz. Achieving the targeted data rates for next generation wireless communication systems requires using frequency reuse ratio 1 in these systems, but this in turn results in significant intercell interference observed especially by the users near cell edges. Cooperation between the base stations plays an important role in reducing the intercell interference. In this paper, we consider the problem of cooperative data transmission from the base stations to the users in multicellular multiple input multiple output (MIMO) orthogonal frequency division multiple access (OFDMA) systems. We propose an efficient cooperative scheduling and data transmission scheme, requiring limited information exchange between the base stations. ©2009 IEEE.

A photoreceiver optoelectronic integrated circuit based on InP with a bandwidth of 37 GHz is presented. The receiver consists of a 50 GHz waveguide-integrated photodiode and a distributed amplifier with a bandwidth of 39.5 GHz, which is composed of four high-electron mobility transistors. A system experiment at 40 Gb/s receiving an return-to-zero coded optical input signal is demonstrated, and a good quality of eye pattern is achieved.