Performance of Massive MIMO System with Cross-layer Design over Composite Rayleigh Fading Channel

In this paper, the cross-layer design (CLD) performance of uplink massive MIMO system is studied by combining the discrete rate adaptive modulation with truncated automatic repeat request over composite Rayleigh fading channel. As shown in the performance analysis, each user's effective signal-to-noise ratio (SNR) and the corresponding conditional probability density function are, respectively, derived. Furthermore, we deduce the switching thresholds for CLD by means of the approximation of the PER with the constraint of the target packet error rate (PER). Based on switching thresholds, using the appropriate numerical integration method, average PER (APER) and overall average spectral efficiency (ASE) of massive MIMO with CLD are derived, and resultant closed-form expressions of APER and ASE can be achieved. The theoretical results above can agree with the corresponding simulations, and thus the system performance can be feasibly assessed. Simulation results illustrate that the CLD system is able to increase the ASE while maintaining the target PER, and thus the theoretical analysis is valid. Besides, with the increase of the maximum retransmission number, the ASE increment will decrease while the PER will increase. Moreover, the system performance will become better with the number of receive antennas increases, as expected.