A New Method of Generating Spectral Nulls at the Transmitter in Cognitive Radio
A New Method of Generating Spectral Nulls at the Transmitter in Cognitive Radio
复制标题
认知无线电发射机处产生频谱零点的新方法
DOI：
10.1007/s11277-016-3207-y
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发表时间：
2016-02
影响因子：
2.2
通讯作者：
Guo, Pei
中科院分区：
文献类型：
--
作者：
Li, Qingwei;Gao, Fei;Fu, Jiangzhi;Guo, Pei
在认知无线电（cognitive radio， CR）中，认知用户可以感知全频谱和白频谱，并在主用户（pu）所占据的频段内产生频谱缺口或干扰。因此，CR的关键技术是控制传输信号的频谱形状，以避免PUs和干扰。本文提出了一种利用扩频技术塑造发射信号频谱包络的新方法。该方法可以在pu波段产生频谱零值，也可以在CR环境下产生干扰。与现有的频谱零值生成方法相比，该方法只需设计基于直接序列扩频技术的伪随机编码波形（PCW），即可有效地生成频谱零值以避免干扰或pu。利用CR技术检测电磁频谱占用情况，从而构建理想的频谱模板。在频谱模板的基础上，研究了基带波形的设计。推导了该方法在不同干扰条件下的误码率（BER）性能，以及误码率与频谱重叠度（SOD）之间的关系，并提出了SOD的概念。BER与SOD之间的表达式表明，BER与SOD成正比，为设计PCW提供了依据。接收机中存在音调干扰和BPSK干扰的信号频谱图表明，该方案可以有效地在被pu或干扰占用的频段产生频谱零值。此外，在音频干扰和BPSK干扰情况下的误码率与信噪比和误码率与SIR仿真结果表明，该方法通过产生频谱零值来避免PUs或干扰，显著提高了误码率性能。仿真结果验证了理论分析的正确性。
In cognitive radio (CR), cognitive users can sense the wholes and white spectrum and generate spectrum notch in the spectrum bands occupied by primary users (PUs) or interference. Thus, the key technology in CR is to control the spectrum shape of the transmitted signal to avoid PUs and interference. In this paper, a new method of shaping the transmitted signal spectrum envelope by spectrum-spread technology is proposed. The proposed method can generate spectral nulls at the band of PUs or interference in the CR environment. Compared to the existing methods generating spectrum nulls, the proposed method can effectively generate spectral nulls to avoid interference or PUs only by designing the pseudo-random code waveform (PCW) based on direct sequence spread spectrum technology. The condition of electromagnetic spectrum occupation is detected by CR technology so as to construct an ideal spectrum template. Based on the spectrum template, we study the design of the baseband waveform. The bit error rate (BER) performance of the proposed method in different sorts of interferences, and the relation between the BER and the spectrum overlap degree (SOD) are derived, of which the concept of SOD is proposed. The expression between BER and SOD shows that BER is proportional to SOD, which shows the criterion to design the PCW. The signal spectrograms in the receiver in presence of tone jamming and BPSK jamming indicate that the proposed scheme can effectively generate spectrum nulls in the frequency band occupied by PUs or interference. Furthermore, the BER versus SNR and BER versus SIR simulation results both in presence of tone jamming and BPSK jamming show that the proposed method has a significantly improved the BER performance by generating spectral nulls to avoid PUs or interferences. Simulation results are carried out to corroborate our theoretical analysis.
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影响因子：
6.8
作者：
Jonathan D. Backens;Chundheng Xin;Min Song;Changlong Chen
通讯作者：
Jonathan D. Backens;Chundheng Xin;Min Song;Changlong Chen
影响因子：
10.4
作者：
Dinesh Datla;R. Rajbanshi;A. Wyglinski;G. Minden
通讯作者：
Dinesh Datla;R. Rajbanshi;A. Wyglinski;G. Minden
DOI：
10.1049/iet-com.2013.1076
发表时间：
2014-11
期刊：
IET Commun.
影响因子：
--
作者：
R. Lin;G. Bi;Xin Liu;Y. Guan
通讯作者：
R. Lin;G. Bi;Xin Liu;Y. Guan
影响因子：
16.4
作者：
Haykin, S
通讯作者：
Haykin, S
影响因子：
1.7
作者：
Badamchi, Bahareh;Nourinia, Javad;Shahmirzadi, Arash Valizade
通讯作者：
Shahmirzadi, Arash Valizade