Narrowband Interference Cancellation for Wireless Communications with Channel Distortion

Download or read book Narrowband Interference Cancellation for Wireless Communications with Channel Distortion written by Sandeep Panthula and published by . This book was released on 2004 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: Code division multiple access (CDMA) implemented with direct-sequence spread spectrum signaling is among the most promising multiplexing technologies for cellular services. The advantages of these include superior operation in multipath environments, flexibility in the allocation of channels and share bandwidth with narrowband communication systems without undue degradation of either performance. The discrepancy in the predictability of narrowband interference and CDMA signal is exploited in this work to propose techniques for narrowband interference cancellation. Linear predictive techniques employed here estimates the interference by processing the past samples and then subtracting it from the received signal to form a signal free of interference. The first proposed method uses this linear prediction model for interference estimation. This method is also used to evaluate the case of multiple received signals at the receiver. The performance of first method degrades with the presence of CDMA signal. So, to account this problem a second method is proposed such that the CDMA signal estimate from the traditional wiener filter is subtracted from the received signal and then it is linearly processed. Linear prediction coefficients are designed using the MMSE criterion to minimize the prediction error.