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A new method for capacity and spectral efficiency increases is a full-duplex communication, where sending and receiving are done simultaneously. Hence, severe interference leaked from the transmitter to the receiver, which can disrupt the system's operation completely. For interference reduction, the transceiver tries to estimate the interfering symbols to remove their effects. A typical method is to use the Hammerstein model. In this method, nonlinear power amplifier (PA) and multipath channel are modeled with a successive nonlinear system and a finite impulse response filter. Then, the model parameters are adjusted, and interference symbols are estimated from the transmitted symbols. In the Hammerstein method, the interference symbols are estimated directly from the transmitted symbols. But practically, the transmitted symbols first pass through the pulse-shaping filter and become a signal. Then, this signal passes through the nonlinear PA and communication channel. Finally, the received signal is filtered by the matched filter (MF) at the receiver and converted to the symbols again. In this procedure, the amplifier and the communication channel affect the transmitted signal directly and distort transmitted symbols indirectly. Therefore, in the practical situation, when we consider the transmitter's pulse-shaping filter and the receiver's MF, the estimated symbols with the Hammerstein method are erroneous. To solve this problem, a new MF at the receiver is proposed and adjusted according to the interfering signal. We have shown that this method is far better than the Hammerstein method. [ABSTRACT FROM AUTHOR]

Continuous-variable quantum key distribution (CV-QKD) provides a theoretical unconditionally secure solution to distribute symmetric keys among users in a communication network. However, the practical devices used to implement these systems are intrinsically imperfect, and, as a result, open the door to eavesdropper attacks. In this work, we study the impact of transmitter stage imperfections on the performance and security of a Discrete Modulated (DM) CV-QKD system using M-symbol Quadrature Amplitude Modulation (M-QAM) and Amplitude and Phase Shift Keying (M-APSK) coupled with Probabilistic Constellation Shaping (PCS). Assuming two different modulation stage topologies, we first deform the constellations and then evaluate the secure key rate achievable with the deformed constellation. The presented results show that, due to the erroneously estimated channel parameters, non-monitored imbalances greatly reduce the system's performance, with situations where Bob and Alice estimate that no secure bits can be obtained while the real value of the key rate is still positive. Our results show the importance of monitoring these constellation imbalances and show that the optimal constellation may vary depending on the degree of device imperfection. [ABSTRACT FROM AUTHOR]

We consider a dual function radar communications network and propose a waveform diversity-based approach to embed both target and scheduling data in the transmitter pulses. The scheduling data of radar signal bandwidth, carrier frequency, and waveform along with the information on target detection, range, and Doppler are shared among the network radar nodes without a need for designated communication links. Scheduling and target information are encoded to bits and transmitted over the radar coherent processing interval using up- and down-chirps. We derive exact expressions of probability of bit error and false alarm rate for sharing scheduling and target information data between two radar nodes. The effect of different parameters and data sharing on the radar performance is analyzed and validated by computer simulations. Using the cross-ambiguity function, we show the capability of the up- and down- chirp sequence transmission scheme in reducing range sidelobes compared to the conventional transmission of only the up- (or down-) chirps. To overcome the limited data rate associated with only using two chirp waveforms, we consider orthogonal chirp division multiplexing and derive its CAF. We demonstrate the suitability of OCDM for high data rate radar operations by examining the mainlobe width and sidelobe levels of the zero-Doppler and zero-delay cuts of the CAF. [ABSTRACT FROM AUTHOR]

Underwater visible light communication emerges as a promising technique to enhance the capacity of underwater wireless communication networks for upcoming generation. Major technical problem with underwater visible light communication systems in motion is the pointing, acquisition, and tracking. To ease pointing, acquisition, and tracking, hence it is important to navigate optical information beam over broad range and adjust the transmitter beam divergence angle according to the link condition, which is adjusted by the Optisystem software. In this paper, performance comparison among wide range of transmittance optical beams in underwater visible light communications system for high-speed communication is presented for PIN as well as for Avalanche photodiode. The effect of using variable transmittance beam-divergence angle on the bit-error rate, signal-to-noise ratio, communication link distance is also investigated. OptiSystem and MATLAB software is used to implement the underwater visible light communication transceiver system. Finally, it is shown in the paper that in the presence of pointing errors, adaptive beam control techniques improve the performance of high-speed Underwater visible light communication system. [ABSTRACT FROM AUTHOR]

In this paper, we propose a signal processing method in passive radar using the multi-user (MU) multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) signal as the illuminator of opportunity. The MU-MIMO-OFDM modulation is adopted in the fifth-generation (5G) communication. We consider the scenario where multiple mobile users share the same time–frequency resources but separate spatially in different beams formed a prior by the MU-MIMO transmitter antenna array, which is a quite general case in realistic 5G communication. A beam-by-beam matched filter is proposed for weak target sensing. Interference suppression is also discussed. The interference in this scenario is more complicated than that in the traditional passive radar. In the MU-MIMO communication system, the base station (BS) transmits multiple signals to different beam regions simultaneously for the communication between the BS and mobile users. For a specific beam region where the radar receiver is located, the interference consists of not only the direct and multipath interference (DMI) of the signal transmitted by the BS to this beam region, but also the inter-user interference (IUI) from the other beam regions. The DMI and IUI degrade the weak target detection capability significantly. In this paper, we propose a suppression method for jointly eliminating the DMI and IUI. Simulations verify the effectiveness of these methods. [ABSTRACT FROM AUTHOR]

Free space optics (FSO) communication is a very recent mechanism. It is mainly needed when physical connection between the transmitter and the receiver is practically impossible and when high bandwidth data transmission is expected. This paper walks through the investigation of the performance of FSO communication adopting spectral amplitude coding optical code division multiple access (SAC-OCDMA) systems at different weather scenarios. The suggested system uses enhanced double weight codes as signature codes by 3 clients, simultaneously. To eliminate multiple access interference and phase induced intensity noise, two different detection schemes are used; single photodiode (SPD) and modified-AND subtraction detection schemes. Furthermore, a comparison between PIN and APD detectors is performed. The performance is evaluated through its propagation distance, received power, Q-factor and bit error rate (BER). The obtained numerical results reveal both Q-factor and BER are modified by 30%. Accordingly, the system performance is enhanced by 30%, when using SAC-OCDMA-FSO with SPD detection technique compared with modified-AND subtraction technique. [ABSTRACT FROM AUTHOR]

The implementation of beamforming schemes on the base station side has been widely employed in recent communication networks. Thanks to the small size of microstrip antenna elements in millimeter-wave (mmWave) frequencies, the implementation of uplink beamforming in small-size user equipments (UEs) is now available and recently becoming popular. The practical implementation of beamforming on the UE side is limited by a variety of challenges and bottlenecks, of which the most significant are the hardware and software complexity as well as power consumption, and hence the low-complexity beamsteering techniques such as analog beamsteering is generally preferred to other schemes on the UE side. In this paper, we consider a mmWave D2D underlaid cellular network, wherein D2D UEs are equipped with low-complexity beamsteering capable antennas. The problem is then formally defined as to find the channel scheduling together with assigning optimal directivity angle and transmit powers of D2D UEs corresponding to the maximum throughput of D2D network. We will employ novel distributed solution approach based on generalized benders decomposition scheme. More specifically, we manage to obtain the closed-form solutions of the primal and master subproblems through which the optimal solution variables can be obtained in a low-complexity distributed scheme. [ABSTRACT FROM AUTHOR]

Massive multiple-input multiple-output (massive-MIMO) is a promising technology for next generation wireless communications systems due to its capability to increase the data rate and meet the enormous ongoing data traffic explosion. However, in non-reciprocal channels, such as those encountered in frequency division duplex (FDD) systems, channel state information (CSI) estimation using downlink (DL) training sequence is to date very challenging issue, especially when the channel exhibits a shorter coherence time. In particular, the availability of sufficiently accurate CSI at the base transceiver station (BTS) allows an efficient precoding design in the DL transmission to be achieved, and thus, reliable communication systems can be obtained. In order to achieve the aforementioned objectives, this paper presents a feasible DL training sequence design based on a partial CSI estimation approach for an FDD massive-MIMO system with a shorter coherence time. To this end, a threshold-based approach is proposed for a suitable DL pilot selection by exploring the statistical information of the channel covariance matrix. The mean square error of the proposed design is derived, and the achievable sum rate and bit-error-rate for maximum ratio transmitter and regularized zero forcing precoding is investigated over different BTS topologies with uniform linear array and uniform rectangular array. The results show that a feasible performance in the DL FDD massive-MIMO systems can be achieved even when a large number of antenna elements are deployed by the BTS and a shorter coherence time is considered. [ABSTRACT FROM AUTHOR]

We consider the Simultaneous Wireless Information and Power Transfer strategy optimization in the two-way transmission relay system under Power Splitting (PS) receiver. In such case, we propose two operational strategies for two-way transmission under PS receiver structure, (1) Delay-Limited-Relay strategy (PS-LDR) and (2) Delay-Tolerated-Relay strategy (PS-TDR). PS-LDR strategy is that both sending node and receiving node need synchronization of information transmission, so communication systems have higher Signal Noise Ratio (SNR) threshold for channels, or communication may break down. In order to explore the performance of PS-LDR strategy, we use outage probability to calculate the analytical expression of the actual maximum throughput (AMT). PS-TDR strategy allows that the information received by the receiving node delays with the information sent by the sending node. Communication system in PS-TDR strategy has lower SNR threshold than that in PS-LDR strategy. The analytical expression of the AMT is calculated by the ergodic capacity in PS-TDR strategy. The influences of system parameters on the optimal throughput in two strategies are discussed. [ABSTRACT FROM AUTHOR]

A scheme for transportation of information with minimum Rayleigh backscattering (RB) noise to the multi-users by employing Qdash laser diode as a source is designed and evaluated. In this paper, employing digital phase shift keying, millimeter wave, 16-quadrature amplitude modulation orthogonal frequency division multiplexing (16-QAM OFDM), and 32-QAM OFDM techniques, the data rates of 4 × 10 Gbps are transmitted simultaneously over 50 km single mode fiber, plus 15 m wireless link, 50 m free space optical (FSO) link, 10 m wireless respectively. Four selective self-injection locked modes of Qdash laser are utilized as optical carriers for downstream and upstream transmission. To ensure the matter of mitigation of RB noise, which mainly arises due to the transmission of light-wave of same wavelengths in bidirectional transportation, the carrier signals of different wavelength are used for modulation and remodulation in optical line terminal and optical network unit. Besides being a strong support to increase the tolerance level against RB noise, this architecture is capable to transmit less noisy information wirelessly in radio frequency sensitive areas too. The constancy of the proposed architecture is evaluated by very low power penalty (~ 1.5–1.7 dB, ~ 2.4–2.6 dB, ~ 1.4–1.6 dB, ~ 1.7–1.8 dB for four channels respectively), clear constellation, prominent eye opening, low bit-error-rate (< 10–9 for pseudo random bit sequence data stream and < 3.8 × 10–3 for OFDM signal) and low error vector magnitude (< 12.4% for 16 QAM, < 10% for 32 QAM). Therefore, the proposed architecture could be promising alternative not only due to the scheme for mitigation of RB noise but also be a potent in the field of applications of the communication world to provide less noisy information to the multi-users (wired/wireless/FSO). [ABSTRACT FROM AUTHOR]

Millimeter-wave (mmWave) and massive multi-input–multi-output (mMIMO) communications are the most key enabling technologies for next generation wireless networks to have large available spectrum and throughput. mMIMO is a promising technique for increasing the spectral efficiency of wireless networks, by deploying large antenna arrays at the base station (BS) and perform coherent transceiver processing. Implementation of mMIMO systems at mmWave frequencies resolve the issue of high path-loss by providing higher antenna gains. The motivation for this research work is that mmWave and mMIMO operations will be much more popular in 5G NR, considering the wide deployment of mMIMO in major frequency bands as per 3rd generation partnership project. In this paper, a downlink multi-user mMIMO (MU-mMIMO) hybrid beamforming communication system is designed with multiple independent data streams per user and accurate channel state information. It emphasizes the hybrid precoding at transmitter and combining at receiver of a mmWave MU-mMIMO hybrid beamforming system. Results of this research work give the tradeoff between multiple data streams per user and required number of BS antennas. It strongly recommends for higher number of parallel data streams per user in a mmWave MU-mMIMO systems to achieve higher order throughputs. [ABSTRACT FROM AUTHOR]

Body channel communications (BCCs) were investigated, to enhance requirements for low power and high-reconfiguration power within permitting technology of wireless measurement systems for wireless communication applications. Standard options for BCC are targeted totally toward channel modeling with a potency measuring technique, a transmission technique, and a wireless transceiver style. Wireless digital transmission designed as a personalized methodology meant for the body channel offers significantly the necessary pathway to implement versatile and low-power BCC systems. In addition to the developing level of wearable communication protocol and applications, there is also an increasing reliability on a flexible BCC transmitter which helps to reconfigure power and meet power reduction conditions. This paper proposes an ultra-low-power, Hamming encoding-based, and body channel communication receiver for wireless body area network applications. Proposed BCC transmitter uses a channel of 1–100 MHz frequency to enhance the transmitter frequency and time domain properties. Hamming-based BCC transmitter makes use of a two-stage low-power analog processing circuit and digital information restoration circuit. Analog processing circuit consists of a dual op-amp adjustable preamplifier. Proposed BCC transceiver has higher data reliability because of the orthogonal characteristic of the Hamming codes. Moreover, the proposed Hamming code concatenated method strengthens the jitter tolerance and improves the code rate. Proposed BCC transceiver was verified using a field-programmable gate array board. Proposed data transceiver achieves a data speed rate of 20 Mbps. Bit error reduction values achieved were < 10−6 and < 10−5 at 60 Mbps and 100 Mbps, respectively. It uses a primary space of 0.14 mm × 0.2 mm when it is functioning below a 15 Mb/s data rate (low-power) condition. BCC transmitter utilizes the power of only 1.0 mW. [ABSTRACT FROM AUTHOR]

In this paper, we consider an energy harvesting device-to-device (D2D) communication system, where D2D transmitter can use mode A to directly communicate with D2D receiver or use mode B as a relay to assist cellular communication while communicating with D2D receiver by adopting non-orthogonal multiple access technology. Firstly, the outage probability expression in two modes is derived, and the communication mode is determined according to outage performance. Then, assuming that the full system information is available, the channel allocation and relay selection are completed by Kuhn–Munkres algorithm, and the offline power allocation of D2D users is realized by reinforcement learning. Next, the offline optimization results are taken as the training data set to train the neural network, and the optimal model of the transmission power is obtained. Considering the transmission power constraint, the online power allocation optimization algorithm is further proposed. Numerical results demonstrate the accuracy of derived outage probability, and the proposed resource allocation algorithm can improve the performance of hybrid system. [ABSTRACT FROM AUTHOR]

Cybersecurity has become a major concern in the modern world. A serious threat to wireless networks is eavesdropping. On the other hand, usable spectrum is diminishing due to the presence of various wireless services. To address the problem, highly spectral efficient methods have been introduced e.g. spectrum sharing. Cognitive radio networks could sense unused spectrum and make use of it. In this paper, the cognitive radio is to perform a second task, i.e. jamming the eavesdropper. This paper is significant in revealing the cognitive radio's energy efficiency in this setting, where a cognitive transmitter (CT) can transmit its own data when it senses the absence of primary transmitter (PT). If PT is present, CT is to jam an eavesdropper (EA) by transmitting artificial noise. Our main contribution is finding the CT's optimal energy efficiency. Through the proposed formulas, we have determined the fractions of time and power required by CT to achieve the optimal energy efficiency, subject to constraints like minimum required secrecy rate Rs, etc. Our major findings are: (1) only a small portion of a time frame (66 μs in our setting) is required for sensing. CT can utilize the remaining time for sending its data or jamming EA. (2) To achieve a target energy efficiency of 0.5 bps/Hz/J, PT should not be actively transmitting more than 35% of the time, and Rs should not be larger than 1.2 bps/Hz. [ABSTRACT FROM AUTHOR]

Due to the spectrum scarcity in conventional celluar frequency bands, millimeter wave (mmWave) frequency bands are attracting increasing attention as a promising candidate for future wireless cellular communication networks. The performance analysis in terms of coverage and rate of mmWave network is a crucial aspect and has been received an increasing interest in recent literature. However, the impact of LoS/NLoS propagation and outage on the coverage probability and rate of the mmWave network is yet to be completely understood. In this paper, we analyze the performance of mmWave networks considering (a) only Non Line-of-Sight (NLoS) environment and (b) both NLoS and LoS propagation. In particular, we compare the coverage and rate performances of mmWave networks with a more practical blockage model that encompasses an outage state, standard path loss function,and directional beamforming which is implemented using number of antennas and scanning angle at the transmitter and receiver. Further, for more practical and precise analysis, we assume that channel amplitudes are Nakgami-m distributed with different fading parameters for NLoS and LoS communication links. Also, different from existing works, the user association with a BS is assumed with a LoS/NLoS path with the smallest pathloss. Our numerical results depict that the presence of an outage state in blockage model decreases the performance of mmWave network. Also, we show the presence of LoS propagation increases the performance of network at the small average cell radius. Further, the impact of variable number of transmit antennas, scanning angle, and antenna radiation efficiency on the network performance is also addressed. [ABSTRACT FROM AUTHOR]

In order to improve the access efficiency of multimedia communication system and solve the problem of two-way link collaboration effectively, based on the collaboration between uplink and downlink, an adaptive multimedia streaming segmentation access mechanism is proposed. First, the multimedia communication system is divided into the transmitter division module, the receiver modular module and the relay network joint control module. In the sending end, the segmentation and flow mapping of multimedia streams are implemented. At the receiving end, the flow control of the multimedia sub-stream and the reorganization of the split flow are realized. The relay network realizes the area division and error detection of the channel capacity. Secondly, the downlink of the multimedia communication system is divided into the parallel multimedia data stream of the server cluster and multiple concurrent users. After interweaving the downlink and the uplink of the multimedia stream segmentation, the cooperative parallel multimedia stream is formed. At the same time, the interleaving weight of the downlink and the weightings of the uplink are combined in order to coordinate the area division and Realization of the channel capacity of the duplex link. Finally, simulation experiments verify the feasibility and effectiveness of the proposed algorithm in terms of resource utilization, wireless access accuracy and efficiency, and multimedia communication quality. [ABSTRACT FROM AUTHOR]

The possibility of using acousto-optic multiband filters for construction of code division multiple-access communication networks has been experimentally proved. Correlation interference has been studied for a set of bands with a spectrum close to sin(x)/x function which are used for encoding/decoding. For the case of several transmitters, a special technology was developed and realized that made it possible to perform studies on a transmission line based on two filters. The key component of this technology lies in emulating the sum signal from two to five transmitters on the first filter. The measured signal-to-interference ratio was more than 11 dB and decreased by less than 3 dB due to correlation interference from the network neighborhood and the emulation error of the sum signal. [ABSTRACT FROM AUTHOR]

In performing short-distance, high-data-rate wireless communications using ultra-wideband (UWB) systems, it is necessary to reduce the average transmission power and ensure a fixed synchronization error between the transmitter and receiver ends. Furthermore, to reduce multipath interference, the UWB system should be sometimes implemented using a rake receiver. However, for such receivers, the delay time and attenuation loss over each transmitted route must be known in advance. In the present study, the complexity of rake receivers with a large number of 'fingers' is reduced by means of a delay-hopped transmitted-reference (DHTR) scheme, in which the delayed signal is correlated with the original signal; thereby avoiding the need for a separate template signal. The synchronization performance of the proposed DHTR receiver is analyzed both theoretically and numerically. An effective timing synchronization scheme, designated as 'parallel signal acquisition with shared looped delay-line' (PS-SLD), is then proposed. The simulation results show that for multipath environments with a single user, the proposed synchronization scheme achieves a higher detection probability and a lower normalized mean square error (MSE) than the traditional timing dirty templates (TDT) algorithm. [ABSTRACT FROM AUTHOR]

Specific emitter identification (SEI) designates the unique transmitter of a given signal, using only external feature measurements called the RF fingerprints of the signal. SEI is often used in military and civilian spectrum-management operations. The SEI technique has also been applied to enhance the security of wireless network, such as VHF radio networks, Wi-Fi networks, cognitive radios, and cellular networks and so on. According to the state of a given signal, SEI techniques can be split into two groups, namely transient signal techniques and steady state signal techniques. Owing to several challenges, transient signal techniques may be limited in practice. On the contrary, steady state signal techniques are more practical. In this paper, a SEI method belonging to steady state signal techniques is proposed. The method works based on the actual signal's inherent nonlinear dynamical characteristics. Firstly, several measurements are acquired from the given signal. Secondly, permutation entropy is utilized to extract the nonlinear dynamical characteristics of these measurements as the signal's RF fingerprint to identify the unique transmitter. DSSS-QPSK signals from WLAN cards, OFDM-BPSK, OFDM-16QAM, DSSS-CCK4b and DSSS-DQPSK signals from digital radios are used to evaluate the performance of the proposed method. Experimental results demonstrate that the proposed method is effective. [ABSTRACT FROM AUTHOR]

Synchronization is an important issue for a communication system to decode the received symbols correctly. Basically, synchronization process includes the time and frequency offsets prediction and compensation. If there are Time Offset (TO) and Carrier Frequency Offset between the Transmitter (Tx) and Receiver (Rx), OFDM system will suffer the Inter-Symbol Interference and Inter-Carrier Interference that degrade the system performance dramatically. In this paper, we propose a low complexity time synchronization and sector identification (ID) method using the unique null sub-carrier feature of the Primary Synchronization Signal and the Second Synchronization Signal for the LTE system. Combined with the down-sampling technique, computer simulations and experimental results show that the proposed method can predict the TO and sector ID correctly and has the advantage of very low computational complexity. [ABSTRACT FROM AUTHOR]

A unified approach based on truncated moment generating function (TMGF) is employed to derive the explicit expressions for channel capacity of log-normal channel under different adaptive transmission policy. The analysis is carried out assuming channel state information known to both transmitter and receiver. The efficacy of the approach is based on the fact it yields computationally convenient and efficient results in log-normal fading environment. Based on TMGF, a simple closed form expression for higher order moments of channel capacity for log-normal channels is obtained when channel state information is only known to receiver. Numerical computation in relation to simulation results for varying value of $$\sigma _{ dB}$$ over permissible range are carried out to validate the accuracy of derived expressions. [ABSTRACT FROM AUTHOR]

The communication efficiency of primary networks in cognitive radio depends on wireless environments, such as obstacles (e.g. buildings), distances between transmitter and receiver, and limited transmit power. A cooperative model between primary and secondary networks has the potential to overcome these problems. In this paper, we propose and analyze the performance of a decode-and-forward scheme with relay ordering for secondary spectrum access. In this scheme, a primary transmitter communicates with a primary receiver with the help of two secondary transmitters. Each secondary transmitter relays primary signals from the primary transmitter to primary receiver, and follows an optimal order to ensure the best communication capacity of the primary network and to find opportunities to transmit its own signals. The performance of primary and secondary networks is evaluated by theoretical analysis in terms of outage probability. Monte Carlo simulations are presented to verify the theoretical analysis and to compare the performance of the proposed protocol with that of a direct transmission protocol and a decode-and-forward protocol with a relay selection scheme. [ABSTRACT FROM AUTHOR]

Cognitive radio requires that a secondary user (SU) stops its transmission as soon as possible upon the arrival of a primary user (PU). In this paper, we propose a novel approach to quickly detect PUs while an SU transmission is in progress. The proposed method requires an SU transmitter to use OFDM to insert periodic zero-energy intervals in a selected subcarrier and to detect energy during each interval for PU detection. The length and periodicity of these intervals determine the performance of PU detection. We also discuss how to determine the energy detection threshold. [ABSTRACT FROM AUTHOR]

Standard power control techniques are not deployable in Aloha networks due to lack of central controlling entity and/or inefficiency of such algorithms in large networks with bursty traffic. To handle this problem in practice, simple transmission power selection algorithms are used for ranging and/or combating harsh channel conditions. In such algorithms, the transmission power is steadily increased by an amount called power step, until the packet is successfully transmitted. Noting that ranging is the major concern of this approach, small power steps are ideal for its operation. However, as we will show in this paper, using small power steps with this algorithm causes a throughput collapse in large networks, when capture effect is considered in the analysis. In the asymptotic case, the throughput of this algorithm will be less than the throughput of the Binary Exponential Backoff (BEB) scheme which only uses a single power level. To show these results, we will present an asymptotic analysis of this algorithm with small power steps in an ideal communication channel where BEB is used as the retransmission scheme. In order to strengthen the results, we will prove the existence of better choices for power steps by extending the analysis for large power steps and we will show that properly chosen large power steps guarantee higher throughputs and require approximately the same average powers as small power steps. Our analysis and simulation results show that small power steps should be avoided with the mentioned power selection algorithm except probably for ranging and once the ranging process is complete, larger power steps should be used to exploit the capture effect. [ABSTRACT FROM AUTHOR]

Abstract  In this paper, we present an analytical model to quantify the effect of the Ultra-Wide Band (UWB) transmitters on the CDMA-PCS downlink range and normalized capacity. The effect is given for different configuration and environments. Our analysis shows that, for a single UWB transmitter, an UWB power density of −78dBm/MHz is the maximum permitted power density to have only PCS macrocell capacity reduction of 1% when the distance between the PCS mobile and the UWB transmitter is 1 m. For the multiple UWB transmitters case, a power density of −80dBm/MHz, is the maximum permitted power density to have only PCS macrocell capacity reduction of 1% when the distance between the PCS mobile and the UWB transmitter is 1 m. [ABSTRACT FROM AUTHOR]