Collaborative Wideband Signal Decoding using Non-coherent Receivers

Abstract

In recent years we are experiencing an important growth of interest for sensing the electromagnetic spectrum and making its access more agile. Emerging initiatives use low-cost receivers in large deployments for sensing the radio spectrum or collecting air-traffic signals at large scale. One of the major drawbacks of low-cost spectrum receivers is their limited sampling rate, which does not allow to decode wideband signals. In order to circumvent the hardware limitations of single receivers, we envision a scenario where non-coherent receivers sample the signal collaboratively to cover a larger bandwidth than the one of the single receiver and then, enable the signal reconstruction and decoding in the backend. We present a methodology to enable the signal reconstruction in the backend by multiplexing in frequency a certain number of non-coherent receivers in order to cover a signal bandwidth that would not otherwise be possible using a single receiver. We propose a method that does not use the knowledge of the modulation scheme, and has been designed to be transparent to the subsequent decoding process. As such, it is equivalent to the reception of the signal by a high-end receiver. We demonstrate and evaluate our approach with two non-coherent receivers which collaboratively sample an aviation signal of almost twice the bandwidth of each receiver. The experimental results show that, using two non-coherent receivers, our method is able to reconstruct and decode correctly more than 80% of data.