HARQ protocols for cooperative networks

这项研究计划的目的是增加我们的基本原则，限制和权衡有关的部署所谓的HARQ协议在协作通信网络的理解。网络中的终端之间的协作被视为增加无线环境中的通信的覆盖范围、速率和可靠性的方式。它通常采取中继的形式，其中终端相互帮助将信息传递到各自的目的地。在无线环境中，传输错误是不可避免的，因此有必要考虑经由所谓的混合自动重传请求（HARQ）协议的重传。虽然它是点对点通信中的公知机制，但是在协作网络的上下文中部署HARQ并不是微不足道的，因为重传可能性的数量由于许多终端的存在而显著增加。由于中继器可以使用所谓的网络编码，因此增加了该问题的另一个维度，并且因此重要的是阐明和分析如何将其与基于中继器的HARQ有效地组合。

The objective of this research program is to increase our understanding of the fundamental principles, limitations, and trade-offs related to the deployment of the so-called HARQ protocols in the collaborative communications networks. The collaboration between the terminals in the network is seen as a way to increase the coverage, the rate, and the reliability of the communication in the wireless environment. It usually takes the form of relaying, where the terminals help each other to convey information to their respective destinations. In the wireless context, the transmission errors are unavoidable so it is necessary to consider retransmission via the so-called hybrid automatic repeat request (HARQ) protocol. While it is a well-known mechanism in point-to-point communications, deploying HARQ in the context of collaborative network is not trivial because the number of retransmissions possibilities is significantly increased due to the presence of many terminals. Another dimension to the problem is added since the relays may use the so-called network-coding and thus it is important to elucidate and analyze how to combine it efficiently with the relay-based HARQ.