Remote Video Interception System Implemented On USRP

With the development of the technology, life is filled with a growing number of information equipment. When they work, a great deal of information will be radiated. The leaked information caused serious threat to information security. The traditional intercept and recovery system composed of AD and DSP devices is not only expensive, but also not easy to carry. More importantly, it is often difficult to reconstruct the image with high resolution. In addition, related parameters configuration is complex,the operation is not convenient. In this paper, a hardware and software system is built with low cost, simple operation and superior performance based on USRP. And the system has more obvious advantages compared to the traditional system composed of AD and DSP devices. It is small in size, inexpensive, reconfigurable, and it is convenient to operate. And a new method to extract the line sync signal called cepstrum is proposed in this paper. The traditional method is to use the external signal generator to generate a line sync signal, or by spectral analysis method or signal autocorrelation to extract the synchronous information. The signal is becoming a triangular spectrum after the autocorrelation. The spectrum is horizontal using the cepstrum method, it is more conducive to find the interval between the neighboring peaks. Finally, we reconstruct the smallest of the 16 font in the display clearly.