Distributed processing techniques for beamforming in wireless sensor networks
Distributed processing techniques for beamforming in wireless sensor networks
复制标题
无线传感器网络中波束形成的分布式处理技术
DOI：
10.1109/icscs.2009.5412692
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发表时间：
2009
期刊：
影响因子：
--
通讯作者：
A. Ghrayeb
中科院分区：
文献类型：
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作者：
Keyvan Zarifi;S. Affes;A. Ghrayeb
无线传感器网络 (WSN) 分布式波束成形 (DBF) 技术的主要任务是最大化接入点 (AP) 处的接收信号功率，同时对意外接收器造成较小的干扰影响。当 DBF 节点不知道非预期接收器的方向时，可以通过形成具有指向 AP 的窄主瓣的波束方向图来显着减少对后者接收器的干扰。然而，这种方法要求 DBF 节点零星地分散在大范围内，因此增加了其互连丢失的可能性。假设节点均匀分布在网络中，我们展示了如何智能选择 DBF 节点来改善网络断开问题。反过来，当非预期接收器的方向已知时，人们可能旨在应用所谓的零点引导波束成形方法来有效地消除这些方向上的接收功率。然而，可以证明，在 WSN 中实现零点引导波束形成器需要每个节点了解网络中所有其他节点的位置；反对 WSN 分布式特性的要求。对于这种场景，我们使用另一个适合分布式实现的波束形成器来近似零转向波束形成器。
A main task in distributed beamforming (DBF) techniques for wireless sensor networks (WSNs) is to maximize the received signal power at the access point (AP) while inflicting small interfering effect on unintended receivers. When the DBF nodes are unaware of the directions of unintended receivers, interference at the latter receivers may be substantially reduced by forming a beampattern with a narrow mainlobe that is pointed towards the AP. However, such an approach requires the DBF nodes to be sporadically scattered over a large area and, hence, increases the probability of the loss of their inter-connection. Assuming that nodes are uniformly distributed in the network, we show how the DBF nodes can be intelligently selected to ameliorate the network disconnectivity problem. In turn, when the directions of unintended receivers are known, one may aim to apply the so-called null-steering beamforming approach to effectively nullify the received power at those directions. However, it can be shown that implementing a null-steering beamformer in WSNs requires each node to be aware of the locations of all other nodes in the network; a requirement that opposes the distributed nature of WSNs. For such a scenario, we approximate the null-steering beamformer with another beamformer that is amenable to a distributed implementation.