Extending coverage area in none line-of-sight MIMO communications using passive repeaters

Annotation: In MIMO communications, high buildings in cities and other obstructions can prevent the propagation of radio waves, resulting in blind spots and poor communications. This problem can be solved using passive repeaters, which, by distributing them in the communication environment, the blind spots can be accessed and the coverage area can be extended. The distribution of these repeaters in the MIMO communication should be optimized in order to maximally cover the target area. In this article, an approach based on non-negative least square (NNLS) algorithm is proposed for optimizing the distribution of the minimum number of repeaters in none-line-of sight (NLOS) MIMO communications. The proposed approach is implemented using passive repeaters consisting of two parabolic antennas connected through a flexible cable. The numerical analysis is performed to verify the validity of the proposed approach, and it is found that the proposed method helps to optimally distribute passive repeaters and extend coverage area with minimum number of repeaters.

Keywords: mimo, non-line-of-sight, nnls, blind spots, passive repeater