Abstract: Existing research on MIMO ( Multiple -Input Multiple -Output) backscatter communication mostly improves reliability at the cost of rate, which fails to meet the performance requirements of high -rate scenarios. In order to balance the SER(Symbol Error Rate) and transmission rate of MIMO backscatter communication, unlike previous works where the power supplier only serves as an energy provider, an antenna selection -based power supply scheme for MIMO backscatter communication systems is proposed. The essence of the proposed scheme is to select only the power -transmitting antennas corresponding to the links with optimal communication quality to enhance MIMO backscatter communication performance. Rigorous mathematical proofs and numerous simulation results indicate that the proposed scheme can provide significant performance improvement in rate under the same diversity order with respect to the conventional approach, and this gain can also be translated into a significant improvement in SER performance at the same transmission rate. This scheme provides effective theoretical support and technical guidance for high -rate, high -performance transmission in MIMO backscatter communication.

Key words: backscatter communications, multiple -input, multiple -output(MIMO), antenna selection, symbol error rate (SER)