Maximum Likelihood Multiuser Detection with Use of Linear Antenna Arrays
نویسندگان
چکیده
We focus on receiver structures and their performance for DS/CDMA systems in mobile cellular environments in cooperation with a linear antenna array. After reviewing the performance of a single-element antenna (scalar) maximum likelihood (ML) detection for CDMA signals, we analyze two ML detection receiver structures, employing interference suppression and desired signal enhancement, and compare the performance of the receivers with that of a single-antenna ML detection receiver. We derive a maximum likelihood linear array receiver for a synchronous DS/CDMA Gaussian channel, in which an array performs neither interference suppression nor desired signal enhancement. We present an ML decision rule, utilizing the spatial information of users such as angles-of-arrivals (AOAs), and derive an expression of the bit error rate (BER) of a user. The eeect of AOA estimation error is also considered for the BER performance with some numerical examples.
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