Pilots-aided LTE reference signal reconstruction in low SNR reference channel for passive sensing

Reference signal reconstruction is performed to improve the cross-correlation detection performance for passive sensing applications. However, the reconstruction results are unreliable by using the conventional demodulation approaches in some extreme complicated environment, e.g. the seriously cluttered and low signal to noise ratio (SNR) scenarios. This paper proposes a novel LTE reference signal reconstruction method by only utilizing pilot signals to enable the robust cross-correlation detection performance in low SNR reference channel. Numerical results validate that: (1) the pilots-aided LTE reference signal reconstruction algorithm is a feasible solution in low SNR environment for passive radar applications; (2) the cross-correlation detection performance of the proposed algorithm is superior to that of the noisy reference signal scheme when the SNR in the reference channel is lower than approximately -11dB, which is determined by the power ratio between the used pilot signals and the perfectly reconstructed reference signal.