An adaptive modulation algorithm with low complexity for generalized spatial modulation

作者：Liu Jianling; Chen Zhigang^*; Wang Lei

来源：Journal of Xi'an Jiaotong University, 2016, 50(4): 48-53 and 67.

DOI：10.7652/xjtuxb201604008

• Joint optimization
• Lower complexity
• Minimum euclidean distances
• Modulation algorithm
• Modulation constellations
• Spatial modulations
• System spectral efficiency
• Transmit antenna

A new adaptive modulation algorithm for generalized spatial modulation (AGSM) is proposed to make full use of the channel state information. The algorithm realizes the joint optimization of antenna combinations and symbol modulation constellations by using the known channel state information and maximizing the minimum Euclidean distance of space-modulation constellation points so that the system performance is improved. Furthermore, a low-complexity AGSM algorithm (LA-GSM) is proposed to reduce the complexity of the joint optimization of antenna combinations and symbol modulation orders. The LA-GSM achieves a lower complexity and makes full use of the antenna combinations of GSM systems by reducing the number of available symbol modulation constellations and searching the identical symbol modulation constellations from the typical antenna combinations and remanent antenna combinations adaptively and respectively. Simulation results show that both the AGSM and the LA-GSM achieve much lower BER performance than the GSM does at a cost of certain complexity under same system spectral efficiency 5 b/(s·Hz) and 6 transmit antennas. Especially, the AGSM's BER and LA-GSM's BER are 1/10 and 1/3 of GSM's one, respectively, when the SNR is high. Moreover, the LA-GSM achieves a better trade-off between lower BER performance and lower complexity.

• 出版日期2016