Opportunistic Spectrum Sharing Based on OFDM With Index Modulation
Opportunistic Spectrum Sharing Based on OFDM With Index Modulation
复制标题
基于索引调制 OFDM 的机会频谱共享
DOI：
10.1109/twc.2019.2943159
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发表时间：
2020
影响因子：
10.4
通讯作者：
Chen Fangjiong
中科院分区：
文献类型：
--
作者：
Li Qiang;Wen Miaowen;Dang Shuping;Basar Ertugrul;Poor H. Vincent;Chen Fangjiong
提出了一种基于正交频分复用和索引调制的认知无线电机会频谱共享方案。在所考虑的基于OFDM-IM的CR（OFDM-IM-CR）模型中，主发射机（PT）借助于放大转发（AF）中继通过发送OFDM-IM信号与主接收机通信。同时，辅发射机（ST）被动地感测频谱，并且如果PT $1到PT $ ST链路的信噪比高于预定义阈值，则通过主网络的那些不活动的子载波将其自己的信息发送到辅接收机;否则，ST保持在静默模式。两种不同类型的最大似然（ML）检测器设计的主网络，基于估计的信道状态信息或统计的次级网络的信道信息的知识。一个复杂性降低的方法，这是适用于这两种类型，并达到接近最佳的性能，进一步提出。为了评估性能，推导出一个严格的上界的误码率（BER），假设第一种类型的ML检测。仿真结果证实了分析，并表明OFDM-IM-CR有潜力优于OFDM-CR和OFDM-IM-AF方面的BER与更高的频谱效率。
In this paper, a novel opportunistic spectrum sharing scheme, based on orthogonal frequency division multiplexing with index modulation (OFDM-IM), is proposed for cognitive radio (CR) networks. In the considered OFDM-IM based CR (OFDM-IM-CR) model, the primary transmitter (PT) communicates with the primary receiver with the aid of an amplify-and-forward (AF) relay by transmitting OFDM-IM signals. Meanwhile, the secondary transmitter (ST) passively senses the spectrum and transmits its own information over those inactive subcarriers of the primary network to the secondary receiver if the signal-to-noise ratio of the PT $\to $ ST link is above a predefined threshold; otherwise, the ST stays in silent mode. Two different types of maximum-likelihood (ML) detectors are designed for the primary network, based on the knowledge of either the estimated channel state information or the statistical channel information of the secondary network. A complexity-reducing method, which is applicable to both types and achieves near optimal performance, is further proposed. To evaluate the performance, a tight upper bound on the bit error rate (BER) is derived, assuming the first type of ML detection. Simulation results corroborate the analysis and show that OFDM-IM-CR has the potential of outperforming OFDM-CR and OFDM-IM-AF in terms of BER with higher spectral efficiency.