Almost all conventional spread-spectrum acquisition schemes assume no data modulation or transition during the acquisition period, because the performance of the acquisition process is signlJicantly degraded when data is present. In practical applications, modulation-off requirements during acquisition period cause inconvenience and delays, such as request and acknowledgment before data transmission can initiate. Recently J. Li and S. Tantarantana proposed a serial search acquisition scheme with an additional correlator unit to compensate the effect of data modulation-on during acquisition. Because of the complicated quadruple integral equation involved in the analysis of the noncoherent acquisition method, they left the performance analysis of the noncoherent acquisition scheme as a future work. In this paper, the performance of the proposed noncoherent acquisition scheme has been investigated by simulation under static environment. For practical purposes the proposed acquisition scheme is extended to the investigation of the performance under both Rayleigh fading and Doppler frequency shifted fading environments. The simulation results indicate that the proposed noncoherent scheme performs signlficantly better with data modulation-on than the conventional ones, under both static and fading environments.worst scenarios are when acquisition is not made in the allocated time frame or when the receiver lost acquisition and trying to reacquire the phase, while the transmitter began to transmit data. If a memory-less system is assumed, which is more likely to be a practical situation at this stage, the presence of data will significantly degrade the performance of the conventional acquisition schemes. Especially the change of data polarity, which modulates the PN sequence, contributes to this performance degradation. These drawbacks of the conventional schemes led J. Li and S. Tantarantana to propose a new scheme for acquisition in the presence of data. In their paper [l], they did the mathematical analysis and performance analysis of the proposed system for coherent acquisition under additive white Gaussian noise (AWGN).In this paper, we simulate the performance of the proposed scheme for noncoherent acquisition under AWGN. For all practical purposes, we extended our simulation on the proposed noncoherent acquisition scheme under Rayleigh fading and Doppler frequency shifted fading environments with data modulation-on. Because of the extensive use of spread-spectrum in mobile communication, the analysis considering Doppler frequency shifted fading is pertinent. Section I1 presents the system model. Section I11 discusses simulation methods for the receiver under fading environments. Section IV provides some simulation results. Section V concludes the paper.
Focus of this paper is mainly evaluating the performance of Long Term Evolution (LTE) system in different terrains such as urban, suburban and rural area. The performance parameters such as, Bit Error Rate (BER) and the Data Throughput are reported in terms of Signal to Noise Ratio (SNR). The system parameters taken into consideration are signal to noise ratio (SNR), number of receiving antenna (RxAn), reference channel and duplex mode. All of the simulations were performed in MATLAB, version 2014a simulink. The results are presented in table and graph which gives clear idea of the effect of environment on signal and receiver sensitivity. Also bit-error-rate, an important parameter in case of receiving signal, is analyzed with respect to SNR values. A comparative analysis of bit-error-rate is performed between three areas for same conditions which proves that LTE signal is well suited in a rural area than that of a suburban and urban area.
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