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In order to obtain high spectral efficiency and high-rate packet transmission, this paper has proposed a STBC-OFDM system to solve the problem of Multi-fading Channels for wideband wireless communication system. Considering the Frequency Selective Channels (FSC), the paper gives the many simulation results of BER based on SNR when the system adopted different number of receiving and transmitting antennas,...
In this paper, using the equivalent single-input single-out (SISO) model, we derive the exact symbol error rate (SER) and bit error rate (BER) of orthogonal space-time block codes (OSTBCs) with multiple modulations over flat uncorrelated and correlated Rayleigh fading channels. We provide the impact of antenna correlation on the performance of OSTBCs. The results showed that the symbol error rate...
This paper describes a modulation scheme for TH- UWB systems using pulse position modulated (PPM). For this scheme, a set of overlapped and orthogonal signals are transmitted simultaneously in the same time slot resulting in a composite pulse. And the signals have been discussed analytically for AWGN and multi-path channels. The proposed scheme can achieve an excellent BER performance by using one...
The researches about conditions of the resource allocation algorithm in wireless communication have been done a lot recently. An evaluation model for the adaptive algorithm of MIMO-OFDM system is built in this paper. After formulating system efficiency under static and adaptive conditions, the effect of imperfect channel state information (CSI) to MIMO-OFDM system is analyzed. Analytical and numerical...
In this paper, frequency offset and phase noise influence and its compensation technique are discussed in the DFT-spread OFDM system. Simulation results show that DFT-spread OFDM introduces more interference than OFDM because of DFT spreading phase offset mismatch caused by frequency offset and random phase noise. Data conjugate ICI self-cancellation method is suggested to improve system performance.
Multiple antenna arrays are promising architectures for overcoming the effects of multi-path interference and increasing the spectrum efficiency. In order to be able to investigate these systems, in this article, we derive generalized spatial correlation equations of a circular antenna array for two types of angular energy distributions: a Gaussian angle distribution, and uniform angular distribution...
In this paper, we present the impact of timing jitter on a direct sequence ultra wideband (DS-UWB) system in additive white Gaussian noise (AWGN) and multipath environment. Rake receiver is used to capture the multipath profile. Investigation is performed in ordinary and optimum Rake, each with all Rake (ARake) and selective Rake (SRake). Additionally, the equal gain combining (EGC) maximal ratio...
Multiple antenna arrays are promising architectures for overcoming the effects of multipath interference and increasing the spectrum efficiency. In order to be able to investigate these systems, in this article, we derive generalized spatial correlation equations of a circular antenna array for two types of angular energy distributions: a Gaussian angle distribution, and uniform angular distribution...
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