Maximum-Eigenvalue Detector for Multiple Antenna Ambient Backscatter Communication Systems

This paper investigates the symbol detection of the multiple antenna ambient backscatter communication systems. In particular, to overcome the problem of the noise uncertainty, the maximum-eigenvalue detector is derived from the general likelihood ratio test, and the approximate bit error rate (BER) performance is characterized. The analytical results show that the BER of the maximum-eigenvalue detector converges to a fixed number in large signal-to-noise ratio or number of receiving antennas $M$ regime. Finally, numerical results are presented to confirm the correctness of theoretical analysis, and reveal that the maximum-eigenvalue detector outperforms the energy detector regarding the BER performance.