In this letter, we propose a new convert information embedded spatial modulation (SM) system for secure communications, in which the transmitter tries to send covert information to the specific receiver while keeping the unintended receiver unaware of the transmission. In the proposed system, the covert information bits are conveyed via the activated antenna index while the common information bits are via the modulation symbols. Specifically, the convert information modulation is achieved by carefully designing the space-time mapping principle so that it is disguised as a conventional SM antenna index. Furthermore, an efficient detection scheme is designed for the proposed system. The simulation results show that the proposed scheme with the developed receiver can offer nearly the same performance gain as conventional SM, whereas the unintended receiver can hardly detect the information correctly. Moreover, the average bit error rate (BER) is analyzed, which also validates our simulation results.

中文翻译：

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隐蔽信息嵌入空间调制

在这封信中，我们提出了一种用于安全通信的新的转换信息嵌入式空间调制 (SM) 系统，其中发射器尝试向特定接收器发送隐蔽信息，同时让非预期接收器不知道传输。在所提出的系统中，隐蔽信息比特通过激活的天线索引传送，而公共信息比特通过调制符号传送。具体来说，转换信息调制是通过精心设计空时映射原理来实现的，使其伪装成传统的SM天线索引。此外，为所提出的系统设计了一种有效的检测方案。仿真结果表明，所提出的带有开发接收器的方案可以提供与传统 SM 几乎相同的性能增益，而无意的接收者很难正确检测到信息。此外，分析了平均误码率 (BER)，这也验证了我们的仿真结果。