Magneto-Electric-Dipole-Based Leaky-Wave Radiating Structure with Reduced Frequency-Dependent Beam Squint

Frequency-induced beam squint is probably the biggest hurdle in some cases that limits the application of leaky-wave antennas (LWAs) and leaky-wave radiating structures (LWRSs) to communication systems. In this paper, we derive a frequency-phase condition of guided-wave radiation elements in an LWA or LWRS to prevent beam squint from frequency scanning. It is found out that magneto-electric (ME) dipoles can be used as radiation elements which possess the required frequency-phase condition in a considerable wide band. Over this band of interest, the main lobe direction of the obtained LWA or LWRS based on the ME dipole can be constant. A simulated LWA prototype demonstrates its beam is fixed at -14° from 16.9 GHz to 17.9 GHz with a well suppressed effect of beam squint over the operation band.