Interleaved OFDM Radar Signals for Simultaneous Polarimetric Measurements

A novel pair of mutually-orthogonal radar waveforms is proposed for simultaneous polarimetric measurements (SPM). The proposed waveform pair exploits the orthogonality features between different subcarriers within a single orthogonal frequency division multiplexing (OFDM) chip, and is called interleaved OFDM (I-OFDM). With I-OFDM signals the isolation limitation defined by the bandwidth time (BT) product for frequently used waveform pairs like linear frequency modulated (LFM) and phase-code modulated (PCM) signals, can be overcome. The performance features of I-OFDM signals are theoretically analyzed; the application of I-OFDM signals and the corresponding signal processing scheme in SPM are presented. A significant increase of the polarimetric measurements efficiency by utilization of the proposed I-OFDM signals has been verified by experiments using an operational radar system.