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This paper presents the performance analysis of a realistic Smart Utility Network (SUN) system with low duty signaling design. The main focus of this paper is to evaluate the performance of the SUN system based on the specifications in an on-going industrial standardization activity, the IEEE 802.15.4g. For this purpose, a theoretical framework is constructed to model the transceiver with low duty...
In coding theory, concatenated codes form a class of error-correcting codes that are derived by combining an inner code with an outer code. This is a solution to the problem of finding a code that has both exponentially decreasing error probability with increasing block length and polynomial-time decoding complexity. The work presented in this paper, provides link level performance analysis of non-line...
This paper presents a novel technique to save the transmitting power of spread-spectrum communication systems based on the application of delay diversity. The core idea of this delay-diversity system is to delay two spreading sequences that carry the same information of a bit with respect to each other in order to statistically separate the influence of fading on the same bit in time domain. The theoretical...
Modern communication system is restricted by the underwater communication. the underwater acoustic channel is probably one of the most complex environments for data communication, the main reasons of bit-error-rate in underwater acoustic communication are serious multipath fading and Dopppler shift, the direction of underwater acoustic communication's development is the data transmission with low...
The performance of multi-hop multiple-input, multiple-output (MIMO) communication scenarios is evaluated for space time block coded (STBC) and the proposed distributed cyclic delay diversity (CDD) technique. By increasing the frequency selectivity, multi-stage CDD with low complexity implementation yields significant performance improvement as relaying network. Both diversity techniques based on frequency-correlated...
In a code-multiplexed transmitted-reference (CM-TR) ultra-wideband (UWB) system [8], the reference pulse trains are made orthogonal to the information-bearing signal by code-shifting. The receiver is simple because it avoids the use of an analog delay line. Moreover, the CM-TR UWB system outperforms the original TR-UWB system in terms of error rates. In this paper, we extend the CM-TR concept to transmit...
This paper analyzes the interference in Direct Sequence Spreading Spectrum (DSSS) systems with Selective RAKE (SRAKE) receivers where channel delay is comparable with spreading sequence length. We build an accurate output model of SRAKE receiver and derive the output Signal to Interference-Noise Ratio (SINR) and Bit Error Rate (BER) of SRAKE receiver, taking multipath effect into consideration. Based...
Statistical models for handover scenarios are necessary in order to identify key parameters and to allow proper benchmarking for handover techniques. This is quite a difficult task, since many assumptions have to be made, resulting in a loss of generality. Efforts towards the generation of such models were already made. Although these models show insights into trade offs, they leave some open questions...
The phenomenon of multipath propagation has contributed significantly towards deterioration of quality of signal received in a wireless communication system. Several techniques for multipath mitigation are in use in the current wireless communication technology standards. With the steady rise in the number of wireless devices active in the environment, the concept of beamforming has also gained popularity...
Signals in HF radio channels are suffered from the effect of delay spread, time-varying interference and additive Gaussian noise. The performances of two differential modulation methods FDDD and TDDD for OFDM system are analyzed in this paper. By analysis and simulations, the relationship of the subcarrier bandwidth and BER is demonstrated, which shows that the selection of optimal subcarrier bandwidth...
Pulse position modulation (PPM) is a popularly adopted modulation scheme in the impulse radio based ultra wideband (UWB) systems. In order to shape the spectrum of the signal, a time dither on generated pulses leading to so-called Time Hopping UWB (TH-UWB) is introduced. Although of many advantages, the TH-PPM scheme faces serious challenges which are the cross modulation interference (CMI) and the...
In this paper, the performance of phase hop diversity in multiple input multiple output (MIMO) wireless system is researched. We get the diversity order of the phase hop diversity (PHD) according to the definition of diversity order and discuss the diversity order in different cases. Although diversity order is an important parameter to evaluate the performance of a communication system using diversity,...
Ultra-wideband (UWB) has been considered a viable and an innovative solution for future short-range high-speed wireless communication systems. One of the big concerns for UWB devices to function properly is the narrow band interference (NBI) issue, which must be carefully studied. For this purpose, the performance of UWB communication system over indoor Lognormal fading channel in the presence of...
The bit error rate (BER) of MDPSK-OFDM in frequency domain over fading HF channels is evaluated, and the optimum value of subcarrier number is given and the upper and lower bound of BER is obtained. The convention differential demodulation scheme is sensitive to the value of subcarrier number in time-variant multipath channel. Improved frequency domain differential demodulation (FDDD) scheme for fast...
In this paper, we propose an adaptive M-ary quadrature amplitude modulation (M-QAM) with variable threshold, which adapts the threshold of rate-region boundaries to the variation of feedback delay between the transmitter and the receiver, over independent and identically-distributed (i.i.d) Nakagami-m fading (NMF) channel. The proposed scheme exploits the estimation of instantaneous bit error rate...
Distributed Cooperative Cyclic Delay Diversity (DCCDD) multi-hop relay network is shown to yield superior performance over traditional link network. The benefits provided by increased frequency selectivity caused by the cyclic delays are evaluated through the explicit closed-form BER expressions and maximum achievable throughput [bits/s/Hz]. Towards that end resource allocation strategies in terms...
In this paper, the ground-to-air channel model is studied and the simulation results of the model are provided. Then, we implement it in the improved single carrier frequency domain equalization (SC-FDE) system and compare the transmission characteristics in different conditions. Theoretical analysis and simulation results show that the BER performance of the proposed system can reach 10-7 or even...
Adaptive modulation and coding (AMC) scheme suffers performance degradation with the signaling feedback delay, as channel state information (CSI) is outdated with time variant channel. In this paper, we propose a robust AMC scheme to mitigate the effect of signaling feedback delay, especially in vehicular environments. Channel information estimated in current time interval is utilized to obtain the...
In the OFDMA downlink, obtaining channel state information (CSI) from users is necessary for the base station (BS) to optimize network performance by intelligently allocating resources and scheduling mobile stations (MS). However, the overhead of obtaining CSI is a large burden and therefore, schemes to reduce CSI are necessary for a realizable system. By considering a MS's coherence time Deltatcoh...
Noncoherent multilevel systems have been typically analyzed with spectrally inefficient orthogonal modulation methods. In this paper, we present a novel error probability analysis of energy detected (ED) signals with spectrally efficient multilevel pulse amplitude modulation (PAM). One of the main challenges in the analysis of ED systems with the multilevel PAM is to find analytical methods to evaluate...
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