Partial decision-feedback detection for multiple-input multiple-output channels

The BLAST ordered decision-feedback (ODF) detector is a nonlinear detection strategy for multiple-input multiple-output channels that can significantly outperform a linear detector at the expense of the increased computational complexity. We propose the partial decision-feedback (PDF) detector, a simplified version of the ODF detector that only feeds back one decision. The PDF detector reduces complexity significantly compared to the ODF detector while suffering limited performance loss. For example, over a 5 × 5 Rayleigh fading channel with 64-QAM inputs, the PDF detector is one-third as complex as the ODF detector yet it requires only 0.5 dB more average signal energy to reach a symbol-error rate of 10^-3.