Channel Prediction Aided Multiuser Transmission in SDMA

— Transmit preprocessing employed at the basestation (BS) has been proposed for simplifying the design of the mobile receiver. Provided that the channel impulse response (CIR) of all the BS to mobile station (MS) links is known in advance-even before the signal’s transmission-it is plausible that the different users’ signals may be differentiated with the aid of their unique, user-specific downlink CIRs. Naturally, this non-causal CIR knowledge is unavailable in practice. Hence a natural design option is to estimate the CIRs at the receiver after the BS’s signal was received and convey it using side-information to the BS for its future use. Naturally, the resultant CIR has to be quantized before its transmission. In addition to this quantization error, it also becomes outdated and both imperfections result in an erosion of the achievable transmit preprocessing gain expressed in terms of either the attainable transmit power reduction or the number of users that may be supported...

• Type: Conference
• Year: 2008
• Where: VTC
• Authors: Wei Liu, Lie-Liang Yang, Lajos Hanzo
• Keywords: Communications, Division Multiple Access, Transmit Preprocessing Gain, Unique User Specific, VTC 2008