Collaborative spectrum sensing for opportunistic access in fading environments
Collaborative spectrum sensing for opportunistic access in fading environments
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DOI：
10.1109/dyspan.2005.1542627
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发表时间：
2005-12
期刊：
影响因子：
--
通讯作者：
A. Ghasemi;E. Sousa
中科院分区：
文献类型：
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作者：
A. Ghasemi;E. Sousa
传统上，频谱由政府机构以固定的方式许可给用户，其中被许可人具有访问所分配的频带的专有权。多年来，这一政策一直是保护系统免受相互干扰的法律实践。然而，随着对频谱需求的增加和空闲频段的稀缺，频谱政策改革似乎不可避免。与此同时，最近的测量表明，在受到干扰保护限制的情况下，不同的参与方之间共享频谱的可能性。在本文中，我们研究频谱共享之间的主要持牌人和一组二级用户。为了能够接入未使用的许可频谱，次要用户必须监视许可频带，并且每当没有检测到主要信号时就伺机发送。然而，当用户经历阴影或衰落效应时，检测受到损害。在这种情况下，用户无法区分未使用的频带和深衰落。本文提出并研究了协作频谱感知作为对抗这种影响的一种手段。我们的分析和模拟结果表明，合作可能会提高感知性能显着
Traditionally, frequency spectrum is licensed to users by government agencies in a fixed manner where licensee has exclusive right to access the allocated band. This policy has been de jure practice to protect systems from mutual interference for many years. However, with increasing demand for the spectrum and scarcity of vacant bands, a spectrum policy reform seems inevitable. Meanwhile, recent measurements suggest the possibility of sharing spectrum among different parties subject to interference-protection constraints. In this paper we study spectrum-sharing between a primary licensee and a group of secondary users. In order to enable access to unused licensed spectrum, a secondary user has to monitor licensed bands and opportunistically transmit whenever no primary signal is detected. However, detection is compromised when a user experiences shadowing or fading effects. In such cases, user cannot distinguish between an unused band and a deep fade. Collaborative spectrum sensing is proposed and studied in this paper as a means to combat such effects. Our analysis and simulation results suggest that collaboration may improve sensing performance significantly