Cyclic Minimum Variance Detection of Multirate Ds-cdma Inmultipath Fading Channels

A cyclic minimum variance detector is presented for the blind detection of the higher data rate signals in a multirate asynchronous Direct Sequence Code Division Multiple Access (DS-CDMA) system and which are signaled over a multipath Rayleigh fading channel. The interference viewed by a higher data rate symbol will be periodic in nature due to the presence of a lower data rate symbol, which spans multiple higher data rate symbols. The detector applies a cyclic detection rule along with joint channel estimation. The convergence and tracking properties of the cyclic detector as well as the Bit Error Rate (BER) characteristics are illustrated using simulation examples.