Detection in collision avoidance radar using active versus passive phased arrays

Abstract

This paper presents two designs for phased arrays for collision avoidance radar operating at the 76 GHz band. The two designs for the antenna use a linear waveguide horn array that is fed with a waveguide powerdividing network and is tapered to produce low side-lobe levels for low-error detection. The taper is based on a 40-dB Taylor distribution. The first design uses passive phased arrays that are stacked and bore-sighted in different directions to produce scanned beams through switching. The second design uses a single phased array with MEMS phase shifters embedded in the last stage of the waveguide power divider. The phase shifters are integrated with the help of MIC/MMIC-to-waveguide or waveguide-tocoplanar-waveguide (CPW) transitions that are housed in the waveguide sections that feed the array elements. The antenna and detection system measurement results of the passive array design are presented, along with the simulation results of the active array design.

H-plane corporate waveguide-fed 4-aperture-stacked circular microstrip patch linear array for Ku band applications

“…Over the years, waveguide technology has been mainly used for satisfying low‐loss and high‐power requirements of feeding networks such as in satellite or radar applications. However, high cost and some physical limitations are associated to the waveguide technology manufacturing process compared to other technologies like substrate integrated waveguide (SIW) or microstrip …”

Waveguide-to-CPW transition for an active phased array for collision avoidance radar

“…The basic waveguide feeding network for the horn array is sketched in Figure 1, showing the waveguide medium in which the transition will be housed. The 16 arrays can be replaced with a single active array that employs phase shifters embedded in the waveguide power divider, which are used for fast beam steering and still using the waveguide as a low-loss medium [2]. One of the efficient media for the phase shifter implementation is the co-planar waveguide (CPW).…”