MU-STBC is uniquely redesigned with auxiliary signals superimposed on top of users' data during the transmission process to intelligently cancel inter-user interference and channel effects at the receiver while keeping the reception process much simpler and less power-consuming
In this study, we present a novel multi-user scheme in which space-time block coding (STBC) is exploited for transmitting data in two rounds in a multiple-input multiple-output (MIMO) fashion while orthogonal frequency division multiplexing (OFDM) is utilized as a transmission framework to serve multiple users on the premises that all the resources remain the same. This new scheme labeled as modified multi-user STBC (MMU-STBC) is an enhanced version of conventional STBC-MIMO in terms of exceptionally higher throughput and reliability. Furthermore, uniquely designed auxiliary signals are superimposed on top of users' data during the two transmission rounds (time slots) to intelligently cancel inter-user interference and channel effects at the receiver while keeping the reception process much simpler and less power-consuming. Moreover, we also present a simple equalization step to recover the signals at the receiver while reducing the complexity significantly, resulting in low latency and less processing at the receiver. Additionally, the proposed scheme's performance is inspected and examined by utilizing performance metrics such as bit error rate (BER), throughput error rate (TER), and peak-to-average power ratio (PAPR) while comparing it with the performance of conventional MIMO systems.
Keywords: Alamouti STBC, multi user, MIMO, OFDM, 6G, IoT, diversity, super-positioning.
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