Link-adaptation (LA) is one of the most important aspects of wireless communications where the modulation and coding scheme (MCS) used by the transmitter is adapted to the channel conditions in order to meet a certain target error-rate. In a single-user SISO (SU-SISO) system with out-of-cell interference, LA is performed by computing the post-equalization signal-to-interference-noise ratio (SINR) at the receiver. The same technique can be employed in multi-user MIMO (MU-MIMO) receivers that use linear detectors. Another important use of post-equalization SINR is for physical layer (PHY) abstraction, where several PHY blocks like the channel encoder, the detector, and the channel decoder are replaced by an abstraction model in order to speed up system-level simulations. However, for MU-MIMO systems with non-linear receivers, there is no known equivalent of post-equalization SINR which makes both LA and PHY abstraction extremely challenging. This important issue is addressed in this two-part paper. In this part, a metric called the bit-metric decoding rate (BMDR) of a detector, which is the proposed equivalent of post-equalization SINR, is presented. Since BMDR does not have a closed form expression that would enable its instantaneous calculation, a machine-learning approach to predict it is presented along with extensive simulation results.
翻译:链接适应(LA)是无线通信的最重要方面之一,在无线通信中,发射机使用的调制和编码办法(MCS)与频道条件相适应,以达到某一目标误差率。在单用户SISO(SU-SISO)系统中,通过细胞外干扰,LA通过计算接收器的电平后信号对干涉噪音比(SINR)来进行。在多用户MIMO(MU-MIIM)接收器中使用的相同技术,使用线性探测器的多用户SIMO(MU-MIMO)接收器。后平衡 SINR的另一个重要用途是物理层(PHY)抽取,其中几个PHY(PHY)区块如频道编码器、探测器和频道解码器被抽象模型取代,以加速系统级模拟。然而,对于拥有非线性接收器的MU-MIMO系统系统,没有已知的等同SIMR(MA和PHY)的模拟方法,这个重要问题在这两部分中处理,而SIS-DR的测算方法则是一种闭式的测算结果。