2025 Volume E108.B Issue 3 Pages 282-293
In cooperative systems for multi-antenna techniques, multiple-input multiple-output (MIMO) is essential to enhance the system capacity. For the transmission technique of MIMO systems, there is the combination of the space division multiplexing (SD) and the spatial modulation (SM), and the bit error rate (BER) performance is improved by using the channel ranking QR decomposition with M algorithm maximum likelihood detection (CR-QRM-MLD). And then, the transmission for the phase rotation SM on-off keying (PR-SM-OOK) and the rectangular SD-8QAM is also effective by using the CR-QRM-MLD with the simultaneous and separated searches. On the other hand, there are several assignments of the constellation for the 8QAM, but they are not evaluated in the SD-SM-MIMO. Therefore, in this paper, we propose the combination of the PR-SM-OOK and the rectangular, cross, octagonal SD-8QAMs for MIMO systems.