Code-division multiple transmission for high-speed UWB radar imaging with array antennas

In this paper, we introduced PN signals with Gold codes instead of the conventional short pulse for the UWB radar imaging, which enabled us to simultaneously transmit signals with multiple antennas. This radar system can obtain the observation data within a short time, which does not spoil the advantage of the high-speed imaging by the SEABED algorithm. We have derived the revised SEABED algorithm in order to deal with the antenna arrangement with a fixed receive antenna and multiple arrayed transmit antennas. This proposed radar system is suffered from the range sidelobes due to the auto-correlations and cross-correlations between PN codes. We found a sub-optimum set of sequences to suppress the range sidelobes. The quality of the estimated target image with the proposed sequences is high enough for most of applications.