Title: Experimental Covert Communication Using Software-Defined Radio Show Chinese title

Title: 基于软件定义无线电的实验隐蔽通信

Abstract: The fundamental information-theoretic limits of covert, or low probability of detection (LPD), communication have been extensively studied for over a decade, resulting in the square root law (SRL): only $L\sqrt{n}$ covert bits can be reliably transmitted over time-bandwidth product $n$, for constant $L>0$. Transmitting more either results in detection or decoding errors. The SRL imposes significant constraints on hardware realization of provably-secure covert communication. Thus, experimental validation of covert communication is underexplored: to date, only two experimental studies of SRL-based covert communication are available, both focusing on optical channels. Here, we report our initial results demonstrating the provably-secure covert radio-frequency (RF) communication using software-defined radios (SDRs). These validate theoretical predictions, open practical avenues for implementing covert communication systems, as well as raise future research questions. Show Chinese abstract

Abstract: 关于隐蔽通信，或者低检测概率（LPD）通信的信息论基本极限已经被研究了十多年，得到了平方根定律（SRL）：对于常量 $L\sqrt{n}$，仅能在时频积 $n$ 上可靠传输 $L>0$ 个隐蔽比特。传输更多比特要么会导致被检测到，要么会导致解码错误。 SRL 对可证明安全的隐蔽通信硬件实现施加了重大限制。因此，隐蔽通信的实验验证尚不充分：迄今为止，只有两项基于 SRL 的隐蔽通信实验研究可用，且这两项研究都专注于光学信道。 在这里，我们报告了使用软件定义无线电（SDR）实现的可证明安全的隐蔽射频（RF）通信的初步成果。这些成果验证了理论预测，开辟了实现隐蔽通信系统的实际途径，并提出了未来的研究问题。