Optimal secondary access in retransmission based primary networks via chain decoding
Optimal secondary access in retransmission based primary networks via chain decoding
复制标题
通过链式解码在基于重传的主网络中实现最佳二次访问
DOI：
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发表时间：
2017
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影响因子：
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通讯作者：
Nicolò Michelusi
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文献类型：
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作者：
Nicolò Michelusi
本文研究了二次接入策略的设计，利用时间冗余的重传协议所采用的主要用户（PU），以提高无线网络的频谱效率。次级用户（SU）执行选择性重传以便优化接收机处的干扰消除的可能性。损坏的信号在SU接收器处被选择性地缓冲，然后经由链解码的连续应用被解码[1]。推导了在对PU造成最大干扰的约束下，最大化SU吞吐量的最优SU接入策略，并以封闭形式给出了其性能。示出了这样的策略在SU的三种操作模式之间最优地随机化：1）SU在PU的整个重传间隔上保持空闲，以避免干扰PU; 2）SU仅在解码PU分组之后进行发送，以利用干扰消除; 3）SU总是在PU的整个重传间隔上进行发送，以便利用链解码。最佳随机化由对PU造成的最大干扰的约束确定。它示出的数字链解码达到15%的吞吐量增益相对于一个国家的最先进的计划，其中SU不执行选择性重传。
This paper investigates the design of secondary access policies which exploit the temporal redundancy of the retransmission protocol employed by primary users (PU) to improve the spectral efficiency of wireless networks. Secondary users (SU) perform selective retransmissions in order to optimize the potential of interference cancellation at the receiver. The corrupted signals are selectively buffered at the SU receiver, and then decoded via the successive application of chain decoding [1]. The optimal SU access policy which maximizes the SU throughput under a constraint on the maximum interference caused to the PU is derived, and its performance is found in closed form. It is shown that such policy optimally randomizes among three modes of operation of the SU: 1) The SU remains idle over the entire retransmission interval of the PU, to avoid interfering with the PU; 2) The SU transmits only after decoding the PU packet to leverage interference cancellation; 3) The SU always transmits over the entire retransmission interval of the PU, so as to leverage chain decoding. The optimal randomization is determined by the constraint on the maximum interference caused to the PU. It is shown numerically that chain decoding attains a throughput gain of 15% with respect to a state-of-the art scheme where the SU does not perform selective retransmissions.