Three proposed mobile radio multirate CDMA systems through multipath Rayleigh fading channel

摘要

The main properties of the precombining blind adaptive multiuser detector (PBA-MUD), which is composed of a rake and a minimum output energy receiver (MOE), are low complexity, multiple-access interference mitigation and remarkable near-far resistance in time-varying multipath fading channels scenarios. In this paper the PBA-MUD is applied to a multirate with variable spreading length, CDMA mobile system. Furthermore, a second multirate system is also suggested, using a prerake at the transmitter. This simplifies the receiver while maintaining a good performance. A channel coding is employed for both systems giving an appreciable improvement. Finally, a diversity technique is applied to the first proposed system resulting in an appreciable improvement. The performance measure is the average bit error rate versus the SNR per bit in a single cell environment.