MULTI-ANTENNA TRANSMISSION SCHEME FOR CONVOLUTIONALLY CODED DS CDMA SYSTEM/

In this paper, we discuss the use of convolutional codes with a multi- antenna transmission scheme for DS/CDMA systems. The binary input data to a rate 1/M encoder produces M coded bits, which, in turn, are assi gned to M different antennas and transmitted from each antenna simulta neously. An intentional delay of several chips duration is introduced at each antenna before transmission, which enables a receiver to disti nguish the signals from different antennas. Because the proposed schem e utilizes spatial and lime domains for coding, it can achieve not onl y implicit time-diversity through the use of coding with interleaving, but also space-diversity through the transmission from multiple anten nas. Multi-antenna schemes with convolutional codes can perform better than conventional single antenna schemes with the same codes and tran smission diversity technique with the same number of transmitting ante nnas, especially when a fading is relatively slow and interleaving siz e is limited.