Comparative Studies of Beam-Squinting Effects Between Leaky-Wave and Phased Array Antennas

This paper is dedicated to comparing the similarities and differences between leaky-wave antennas (L WAs) and phased array antennas (P AAs) regarding their beam-squinting effects. It is shown that although a general L W A and phase-shifter-based P AA suffer from a narrow instantaneous bandwidth due to the common issue of beam-squinting, the specific behaviors of their beams as frequency varies are different. In particular, the useful radiation frequency band of an L W A presents a spatial dependence, whereas this phenomenon is not possessed by a phase-shifter-based P AA. On the other hand, it is observed that the time-delay circuits/devices that are usually deployed in wideband P AAs can be properly implemented in L W As to design a class of wide band LWAs featuring fixed-beam radiation. From the authors' perspective, such a comparative study can help general readers grasp basic yet important pictures concerning the frequency- and phase-based beam-scanning architectures.