The previous suboptimal user pairing and optimal power control for uplink multiantenna NOMA systems considers the physical-layer-only to maximize the sum data rates. For video communications, the objective is changed to minimize the sum video distortion and then maximize the peak signal-to-noise ratio (PSNR). For uplink multiantenna NOMA systems, we propose 1) a novel weak set user selection scheme to maximize the ratio of signal power and the interference to the strong set users, 2) a novel iterative user substitution scheme based on video distortion in the application layer that increases the PSNR, and the video quality, 3) a novel optimal power allocation derived to minimize the video distortion in the application layer. 1) considers the physical-layer only and 2) and 3) consider the application layer too. The numerical results indicate that the proposed cross-layer scheme outperforms the previous physical-layer-only by 1.1 dB, and is only 0.8 dB away from the exhaustive upper bound in PSNR with 20 users and SNR = 15 dB. The complexity of the proposed scheme is slightly greater than that of the previous physical-layer-only scheme, but still much lower than that of the exhaustive upper bound.
- cross-layer optimization
- multi-user-multiple-input multiple-output (MU-MIMO)
- nonorthogonal multiple access (NOMA)
- power allocation
- user set selection