Benefits of space-time diversity for radar

When designing a new radar system, standard resolution trade-offs play a major role, providing the basic parameters of the radar, such as size, update rate, and range. Besides, diversity has long been used for mitigating fading effects due to the fluctuation of targets and clutter. However, with the arrival of more flexible systems, using multiple parallel channels on transmit and receive, and wider instantaneous bandwidths, these standard trade-offs are becoming less simple-and more flexible. In this communication, we will analyse the benefits of diversity and its relations with range, Doppler, and angle, for detection and location of moving targets with wideband/wide-beam radar systems. The idea is to contribute to a better understanding of the real benefits of agile transmissions for detection/localization of moving targets, focusing on range, velocity, and angular measurement improvements, as well as on the benefits for detection of moving targets. Special attention will be given to the quality of the different wideband wide-beam sensor modes for long-range surveillance, and new results on detection of moving targets in clutter will be provided to demonstrate the effectiveness of these new architectures for small target detection at long range, in difficult environments. (C) 2019 Academie des sciences. Published by Elsevier Masson SAS.