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处于“死亡谷”的边缘？

认知无线电（CR）的诞生是为了解决二十年前不断发展的用户需求。从那时起，它也被认为是一种减轻各种应用领域中频谱稀缺感的方法。在本文中，通过使用IEEE主题，技术准备水平以及综合能力元模型作为分析框架，通过对2013年至2020年的193篇文章进行系统的文献综述，对军事CR研究的现状进行了评估。军事CR研究的年度分布表明持续的兴趣。军事CR研究似乎在诸如波形设计和安全性等主题上多产，并且不会忘记对CR网络主题的稳定兴趣。涉及应用，服务和标准化的论文数量极少。总的来说，军事企业责任研究似乎是零星的和分散的。我们的数据表明，尚未发生从单个技术，朝着系统工程方法方向的组件级子系统研究以及系统级研究的转变，并且总体TRL仍然很低。缺乏对军事认知无线电系统概念的公开表述的全面处理，这是图形的，并导致子系统级别的研究分散，分散。