Low-complexity improved-throughput generalised spatial modulation (LCIT-GSM) is proposed. More explicitly, in GSM, extra information bits are conveyed implicitly by activating a fixed number $N_{a}$ out of $N_{t}$ transmit antennas (TAs) at a time. As a result, GSM has the advantage of a reduced number of radio-frequency (RF) chains and reduced inter-antenna interference (IAI) at the cost of a lower throughput than its multiplexing-oriented full-RF based counterparts. Variable-${N_a}$ GSM mitigates this throughput reduction by incorporating all possible TA activation patterns associated with a variable value $N_{a}$ ranging from $1$ to $N_{t}$ during a single channel-use, which maximises the throughput of GSM but suffers a high complexity of the mapping book design and demodulation. In order to mitigate the complexity, \emph{first of all}, we propose two efficient schemes for mapping the information bits to the TA activation patterns, which can be readily scaled to massive MIMO setups. \emph{Secondly}, in the absence of IAI, we derive a pair of low-complexity near-optimal detectors, one of them has a reduced search scope, while the other benefits from a decoupled single-stream based signal detection algorithm. \emph{Finally}, the performance of the proposed LCIT-GSM system is characterised by the error probability upper bound (UB). Our Monte Carlo based simulation results confirm the improved error performance of our proposed scheme, despite its reduced signal detection complexity.
翻译:更明确的是,全球通量中,额外的信息比点通过在单一频道使用期间使用一个固定的值$N ⁇ a}美元发送天线(TAS)而默认地传递。因此,全球通量的优势是,无线电频率链数减少,而安全线间干扰(IAI)则减少,其成本低于其多x导向全RF的对应方。变量-${N_a}全球通量中,将所有与可变值$N ⁇ a}相关的可能TA启动模式纳入到一个可变值为美元-美元=美元/美元/美元传输天线的固定数字中,从而可以降低无线电频率链链链链(RF)链条数量,降低安全线间干扰(IAI)的成本,降低其复杂性(emph*),我们建议两个高效的系统来绘制信息比启动模式的启动率(TAAV)减少,在一次测试之前可以快速地进行一次测试。