The LMMSE estimate-based multiuser detector: performance analyses and adaptive implementation

Presented in this article are analytical expressions of the performance measure on the LMMSE estimate-based multiuser detector, including an error probability expression and its computationally and notationally efficient approximations, signal to interference-plus-noise ratio, and asymptotic efficiency. Also included in are adaptive implementation schemes of the LMMSE detector and the equivalent relation between them under appropriate assumptions. Simulations are included to show the tightness of approximate results over a wide range of near-far ratio and various combinations of SNRs of interfering multiple-access users