STBC-assisted OFDM with Subcarrier Power Modulation
In this work, OFDM-SPM technique is compounded with Alamouti space-time block coding (STBC) in a multiple-input-single-output (MISO) setup to study, investigate and quantify the wireless system’s performance of their combination over a wireless multipath Rayleigh fading channel.
STBC-assisted OFDM with Subcarrier Power Modulation
Orthogonal Frequency Division Multiplexing with Subcarrier-Power Modulation (OFDM-SPM) has recently been proposed as a promising, potential transmission technique for future wireless communications(i.e., 6G and beyond) due to its multiple beneficial characteristics, including higher spectral efficiency, low latency with good reliability while maintaining low complexity. In this paper, the OFDM-SPM technique is compounded with Alamouti space-time block coding (STBC) in a multiple-input-single-output (MISO) setup to study, investigate and quantify the wireless system’s performance of their combination over a multipath Rayleigh fading channel. Particularly, we analyze the two main performance metrics, bit-error-rate (BER) and throughput of the newly designed technique called OFDM-SPM-STBC, and then quantify the amount of gains in both BER and throughput. For making STBC work well with OFDM-SPM, a suitable equalizer is proposed for detecting the SPM power bits, and it is observed that there is a considerable improvement in the BER performance. We also consider two scenarios for OFDM-SPM-STBC transmission. The first one is the power reassignment policy (PRP), and the second one is the power saving policy (PSP). It is found that the sub-carrier optimized power-reassignment scheme provides the best BER performance for the proposed transmission scheme. In contrast, the PSP for SPM provided an intermediate improvement in an average BER.
INDEX TERMS: OFDM-SPM, Alamouti STBC, BER, Equalizer, OFDM, Throughput, Subcarrier Power Modulation.
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