Discrete rate spectral efficiency for adaptive MIMO systems

Adaptive modulation scheme has been widely used in multipleinput multiple-output (MIMO) systems to enhance spectral efficiency while maintaining bit-error rate (BER) under a target level. We consider two MIMO schemes, orthogonal space-time block codes (OSTBC) and spatial multiplexing with zero-forcing receiver (SM-ZF), that apply adaptive modulation and derive closed-form expressions of the average spectral efficiency. Based on the closed-form expression of the average spectral efficiency, a low complexity switching method is utilized to gain significant improvement in spectral efficiency over an adaptive modulation system using a single MIMO scheme.

• Type: Conference
• Year: 2008
• Where: ICASSP
• Authors: Jinliang Huang, Svante Signell
• Keywords: Adaptive Modulation, Average Spectral Efficiency, ICASSP 2008, Signal Processing, Spectral Efficiency