Orthogonal waveforms for multistatic and multifunction radar

Modern radar include more and more multiple functions and multiple channels as in the case of MPAR (Multifunction Phased Array Radar) and MIMO (Multiple Input Multiple Output) radar. In this context sophisticated waveforms and related processing (pulse compression, extraction of information) are needed. Moreover, to avoid changes in target RCS and undesirable Doppler effects, the encoded waveforms (one for each channel) have to be transmitted simultaneously and at the same carrier frequency. The orthogonal property is required for the transmitted signals to separate them in reception. A good candidates to design signals that satisfy the orthogonal requirements are the Costas codes (CS) and the Phase Noise (PhaNo) signals. In this paper we present a comparison of the main characteristics of the CS and PhaNo considering as a reference the pair of "up" and "down" chirp (Linear-FM and Non-LFM).