Multiple input multiple output radar: study and evaluation of signal to noise ratio

The multiple input multiple output (MIMO) radar operating in time multiplexing is a consolidated technique that allows angular resolution without moving parts. On the other hand, the MIMO could also be used in monostatic modality by transmitting simultaneously by all the TX antennas, for example for beam steering or for no direction of arrival (no-DOA) applications. In this paper, MIMO is used in this modality to improve the signal to noise ratio (SNR). The evaluation of SNR of a MIMO has been theoretically and experimentally addressed. The authors notice that SNR grows with a quadratic law with respect to the number of TX channels, while it grows linearly with the number of RX channels. The theoretical behavior of SNR as a function of TX and RX channels was experimentally confirmed in a controlled scenario. However, there are certain limitations that can negatively impact this performance, such as leakage effects, especially as the number of TX and RX channel increases. Additionally, there are restrictions on the maximum transmitted power that must be considered