Abstract—Feedback of channel information can be used inMISO precoding to increase link reliability. To reduce theoverhead in feedback signaling channel, codebook basedprecoding scheme is adopted in practical systems includingLTE. However, the size-limited codebook has obviousquantization error which will incur some performance losscompared to the optimal precoding. In this paper, wepropose a new precoding scheme for the codebook basedMISO system. The proposed scheme utilized the PMI reportfrom UE to modify the precoding vector towards theoptimal beamforming vector on per slot basis. Simulationresults indicate that the proposed scheme has obvious SNRgain over the conventional precoding scheme under samefeedback overhead.

Index Terms—precoding, codebook, MISO

Cite: Chengyu. Liu and Hongwen. Yang, "A New Precoding Scheme for the Codebook Based MISO Beamforming," International Journal of Signal Processing Systems,  Vol. 1, No. 1, pp. 98-102,  June 2013. doi: 10.12720/ijsps.1.1.98-102