An adaptative method for determination of WDS in a DS/CDMA system
نویسنده
چکیده
The steeping chip weighting waveforms are used in Multiple Access Interference (MAI) cancellation by emphasizing the received spreading signal, therefore, that allows to solve the problem of orthogonality for the chip waveforms. Our paper presents a useful method based on fuzzy systems to determine the despreading sequences weighted by the steeping chip weighting waveforms for Direct Sequence Code Division Multiple Access (DS/CDMA). The validity of our proposed method has been tested by numerical examples for an Additive White Gaussian Noise channel. We show that the parameter values of the chip weighting waveforms are good and the Bit Error Rate performance of the system does not undergone any degradation. Keywords—DS/CDMA, MAI, Weighted Despreading Sequences (WDS), Fuzzy Systems.
منابع مشابه
Throughput Improvement of STS-Based MC DS-CDMA System with Variable Spreading Factor
The throughput enhancement of Space-Time Spreading (STS)-based Multicarrier Direct Sequence Code Division Multiple Access (MC DS-CDMA) system is investigated in this paper. Variable Spreading Factor (VSF) is utilized to improve the data throughput of the system. In this contribution, an analytical approach is proposed to compute a new expression for the Bit Error Rate (BER) performance of t...
متن کاملNonlinear Multiuser Receiver for Optimized Chaos-Based DS-CDMA Systems
Chaos based communications have drawn increasing attention over the past years. Chaotic signals are derived from non-linear dynamic systems. They are aperiodic, broadband and deterministic signals that appear random in the time domain. Because of these properties, chaotic signals have been proposed to generate spreading sequences for wide-band secure communication recently. Like conventional DS...
متن کاملBit Error Performance for Asynchronous Ds Cdma Systems Over Multipath Rayleigh Fading Channels (RESEARCH NOTE)
In recent years, there has been considerable interest in the use of CDMA in mobile communications. Bit error rate is one of the most important parameters in the evaluation of CDMA systems. In this paper, we develop a technique to find an accurate approximation to the probability of bit error for asynchronous direct–sequence code division multiple–access (DS/CDMA) systems by modeling the multipl...
متن کاملMAI Cancellation in DS/CDMA using a new Approach on WDS
The steeping chip weighting waveforms are used in Multiple Access Interference cancellation by emphasizing the received spreading signal, therefore, that allows to solve the problem of orthogonality for the chip waveforms. The goal of this study was to elaborate a useful method based on fuzzy systems to determine the despreading sequences weighted by the steeping chip weighting waveforms for Di...
متن کاملJoint Closed-Loop Power Control and Base Station Assignment for DS-CDMA Receiver in Multipath Fading Channel with Adaptive Beamforming Method
In this paper, we propose smart step closed-loop power control (SSPC) algorithm and base station assignment based on minimizing the transmitter power (BSAMTP) technique in a direct sequence-code division multiple access (DS-CDMA) receiver in the presence of frequency-selective Rayleigh fading. This receiver consists of three stages. In the first stage, with conjugate gradient (CG) adaptive ...
متن کامل