MIMO surface wave radar using time staggered FMCW chirp signals

In order to distinguish between different signal paths, full orthogonal waveforms for each transmit antenna element is desirable for the concept of MIMO radar. We investigate time staggered Frequency Modulated Continuous Wave (FMCW) chirp signals with an individual successive temporal delay larger than the maximum round-trip time of the radar signal. This concept is superior compared to those using time division multiplexing or multiple carrier frequencies in terms of unambiguous Doppler and bandwidth requirement, respectively. This is in particular important for long range marine surveillance using high-frequency surface wave radar where the frequency band is very congested and fast boats or helicopters have to be detected.