Digital true time delay for pulse correlation radars

A novel concept for digital true time delay pulse correlation radars using digital programmable delay lines and monolithically integrated radar front-ends is investigated. The effects of quantization errors on side lobe level and deviation of beam direction due to the digital true time delay lines are evaluated by numerical simulations based on the performance of commercially available time delay units. To verify the simulation results, a compact 26 GHz active electronically steered linear antenna array consisting of 8 elements has been realized, which provides beamforming in both transmit and receive path. Measurement results and design details of this steerable radar sensor are presented in the experimental part of this paper.