Adaptive Channel Estimation in Pilot Channel based DS-CDMA Systems
نویسندگان
چکیده
The performance of a coherent rake receiver of DSCDMA systems is significantly affected by the accuracy of channel estimation. The performance of the channel estimator can be improved by employing a channel estimation filter (CEF) whose impulse response is adjusted according to the channel condition. In this paper, we consider the design of an adaptive channel estimator for DSCDMA systems with a pilot channel. The proposed channel estimator estimates the channel condition, which can be performed without having exact a priori information on the operating condition. The estimated channel condition adjusts the impulse response of the CEF. Numerical results show that the use of the proposed channel estimator can provide BER performance quite robust to a wide range of channel condition.
منابع مشابه
Adaptive Channel Estimation in DS-CDMA Systems
The accuracy of channel estimation (CE) significantly affects the performance of the coherent rake receiver in DS-CDMA systems. It is desirable to employ a CE scheme that can provide good estimation performance and fast tracking the channel fading with reduced complexity. Such a CE scheme needs to employ a so-called channel estimation filter (CEF) that can effectively reduce the noise effect ac...
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