Fast scalable fixed-point architecture proposal of a QR decomposition for STBC-VBLAST receiver

This work presents a proposal of an implementation of a Sorted QR decomposition using fixed-point arithmetic for STBC-VBLAST space-time scheme. This proposal was verified in the context of a MIMO receiver, the effects of finite-length arithmetic and limited precision are evaluated in terms of their impact on the receiver bit error rate (BER). We will define the minimum fixed-point word size required not to adversely impact performance for n
_t
transmit antennas and n
_R
receive antennas. Our analysis of MIMO receiver under these conditions shows a strong robustness on the numerical precision, which allows to have a receiver performance very close to that obtained with floating point arithmetic in terms of BER, therefore we believe this scheme is attractive candidate for its implementation in current communications standards.