This letter considers the downlink of a cellular network with an asymmetric antenna configuration, where virtual multiple-input multiple-output (MIMO) is formed with receive cooperation over out-of-band or in-band overlay device-to-device (D2D) links. The objective of this work is to determine the best pairing and resource sharing configuration of the cooperative devices such that the overall network utility is optimized and the devices achieve their best available rate larger than that without D2D cooperation. A distributed algorithm is developed via an algorithmic-game-theoretic message-passing framework to obtain a solution at a low computational cost and without reporting the D2D link qualities to the base station. We show that the algorithm converges to an optimal point through analysis and its performance is validated by simulation. In addition, the virtual MIMO network enabled by the D2D receive cooperation is shown to provide a significant gain over the network without the D2D receive cooperation.

A class of low-complexity multi-antenna relaying schemes is proposed for orthogonal frequency division multiplexing based one-way and two-way relay networks. In the proposed schemes, two single-antenna terminal nodes complete the data transfer in two time phases via a multi-antenna amplify-and-forward relay without channel state information, discrete Fourier transform (DFT), and inverse DFT. The relay signal processing consists of receive combining, power scaling, and transmit diversity, where instantaneous time domain power scaling is proposed for power scaling and power-based selection combining and cyclic delay combining are proposed for receive combining, to leverage the performance only with time domain operations. An approximation to the outage probability is also derived to predict the coded performance behavior under practical channel models. It is shown by evaluating the outage probability and coded bit error rate that the proposed schemes outperform the conventional schemes of comparable complexity.