This paper presents a reduced-complexity QRD-M algorithm using partial decision feedback (DF) detection. Adaptive QRD-M algorithm obtains the threshold value through the simulation to prune off paths at each stage. However, the proposed algorithm efficiently acquires the threshold value using partial DF detection at each stage. In 4 × 4 V-BLAST system with 16-QAM, the complexity of the proposed algorithm
is approximately 50 % lower than that of adaptive QRD-M algorithm at Eb/N0 = 16 dB. Moreover, the effectiveness of complexity reduction is especially predominant at low signal-to-noise ratio (SNR).