In this paper, we propose two adaptive cooperation protocols for wireless systems. The first protocol chooses between cooperative communications (CC) and non-cooperative communications (NCC), the protocol that offers the highest instantaneous throughput. The best relay is activated only if the instantaneous throughput of relayed link is larger than that of direct link. The second protocol chooses between CC and NCC, the protocol that maximizes the average throughput. The best relay amplifies the received signal only when the average throughput of relayed link is larger than that of direct link. Both protocols include adaptive modulation and coding to increase the throughput by selecting the appropriate modulation and coding scheme. The results are valid for Rayleigh fading channels where relay nodes use amplify and forward relaying.

中文翻译：

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具有自适应调制和编码的自适应协作协议

在本文中，我们为无线系统提出了两种自适应协作协议。第一个协议在合作通信 (CC) 和非合作通信 (NCC) 之间进行选择，该协议提供最高的瞬时吞吐量。只有当中继链路的瞬时吞吐量大于直接链路的瞬时吞吐量时，才会激活最佳中继。第二个协议在 CC 和 NCC 之间进行选择，这是最大化平均吞吐量的协议。只有当中继链路的平均吞吐量大于直接链路的平均吞吐量时，最佳中继才会放大接收信号。这两种协议都包括自适应调制和编码，以通过选择适当的调制和编码方案来增加吞吐量。结果对于中继节点使用放大和转发中继的瑞利衰落信道有效。