Capacity Gain from Transmitter and Receiver Cooperation

TL;DR

This paper compares capacity gains from transmitter and receiver cooperation in relay networks, highlighting conditions where each strategy outperforms the other and emphasizing the importance of CSI and power allocation.

Contribution

It provides a comprehensive analysis of capacity gains under different CSI and power allocation scenarios, revealing when transmitter or receiver cooperation is more effective.

Findings

Transmitter cooperation outperforms receiver cooperation with full CSI and equal power.

Receiver cooperation can outperform transmitter cooperation with optimal power allocation and limited CSI.

Full CSI is crucial for transmitter cooperation, while optimal power allocation benefits receiver cooperation.

Abstract

Capacity gain from transmitter and receiver cooperation are compared in a relay network where the cooperating nodes are close together. When all nodes have equal average transmit power along with full channel state information (CSI), it is proved that transmitter cooperation outperforms receiver cooperation, whereas the opposite is true when power is optimally allocated among the nodes but only receiver phase CSI is available. In addition, when the nodes have equal average power with receiver phase CSI only, cooperation is shown to offer no capacity improvement over a non-cooperative scheme with the same average network power. When the system is under optimal power allocation with full CSI, the decode-and-forward transmitter cooperation rate is close to its cut-set capacity upper bound, and outperforms compress-and-forward receiver cooperation. Moreover, it is shown that full CSI is essential in transmitter cooperation, while optimal power allocation is essential in receiver cooperation.