Design of Channel Estimation Filters for Pilot Channel Based DS-CDMA Systems
نویسندگان
چکیده
The accuracy of channel estimation significantly affects the performance of coherent receiver in a DS-CDMA system. The receiver performance can be improved if an appropriate channel estimation filter is used according to the channel condition. In this paper, we consider the design of channel estimation filters for pilot channel based DS-CDMA systems. When a moving average (MA) FIR filter is used as the channel estimation filter (CEF), the tap size is optimized by minimizing the mean squared error of the estimated channel impulse response. Finally, the analytic design is verified by computer simulation. Numerical results show that the optimum MA FIR CEF provides near optimum performance, i.e., quite similar to that with the use of Wiener filter. key words: channel estimation filter, DS-CDMA system, pilot channel
منابع مشابه
Bit 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 کاملZero-delay Channel Estimation Based on Pilot and Traffic Channels for Ds/cdma Systems
Abstract In this paper, a zero-delay channel estimation scheme based on both pilot and traffic channels is proposed for next generation direct sequence codedivision multiple-access (DS/CDMA) systems. This scheme has no channel estimation delay, and is found to perform significantly better than a zero-delay channel estimation scheme based on only pilot channel. The elimination of channel estimat...
متن کاملE ffi cient Channel Estimation in DS - CDMA Systems ∗
The accuracy of channel estimation significantly affects the performance of coherent rake receiver in DS-CDMA systems. It is desirable for improved channel estimation to employ a channel estimation filter (CEF) whose bandwidth is adjustable to the channel condition. In this paper, we consider the use of moving average (MA) FIR filters as the CEF since it is simple to implement and can provide r...
متن کاملPerformance Analysis of ZF Pre-Coder and Extended Joint Channel Estimation Method in Downlink CDMA with HPA
In the down link scenario of code division multiple access (CDMA) systems, multi user detectors (MUDs) such as linear de-correlating detector (LDDs) provide satisfactory symbol error rates (SERs) at the expense of much increased complexity, they require all active users’ spreading sequences, which is impractical from privacy point of view. To overcome this impracticality, a simple matched filte...
متن کاملPilot Aided Channel Estimation for Short-Code DS-CDMA
This paper investigates pilot based channel estimation techniques for short code DS-CDMA in a multipath environment. It will be shown that the conventional correlative estimation algorithm is biased and very sensitive to multi-user interference (MUI). Therefore, we suggest two advanced estimation algorithms. The first one eliminates the inherent path cross talk and yields an unbiased estimate w...
متن کامل