Cognitive radio (CR) was coined to address evolving user needs two decades ago. Since then, it also has been considered a way to mitigate perceived spectrum scarcity in various application areas. In this article, the status of military CR research is assessed through a systematic literature review of 193 articles, from 2013 to 2020, using IEEE thematic topics, technology readiness levels, as well as comprehensive capability meta-model as analytical frameworks. The annual distribution of military CR research indicates continuing interest. The military CR research seems to be prolific on topics like waveform design and security, not forgetting a steady interest in CR networking topics. Significantly low numbers of papers address applications, services, and standardization. In general, military CR research seemed sporadic and scattered. Our data suggest that a transition from individual techniques, component-level subsystem research in the direction of systems engineering approach, and system-level studies has not yet happened, and the overall TRLs remain low. The absence of publicly articulated comprehensive treatment of the notion of military cognitive radio system is graphic and has led to disjointed, scattered research at the subsystem level.

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系统文献综述：军事认知无线电系统是否已濒临“死亡走廊”？


认知无线电（CR）是二十年前为了满足不断变化的用户需求而创造的。从那时起，它也被认为是缓解各种应用领域频谱稀缺的一种方法。本文以IEEE主题、技术成熟度以及综合能力元模型为分析框架，通过对2013年至2020年193篇文章的系统文献回顾，评估了军事CR研究的现状。军事 CR 研究的年度分布表明了持续的兴趣。军事 CR 研究似乎在波形设计和安全等主题上非常丰富，同时也没有忘记对 CR 网络主题的稳定兴趣。涉及应用程序、服务和标准化的论文数量明显较少。总体而言，军事CR研究显得零星且分散。我们的数据表明，从个体技术、组件级子系统研究向系统工程方法和系统级研究方向的转变尚未发生，总体 TRL 仍然较低。军事认知无线电系统概念缺乏公开明确的综合处理，这导致子系统层面的研究脱节、分散。