Frequency-Scanned Monopulse Pattern Synthesis Using Leaky-Wave Antennas for Enhanced Power-Based Direction-of-Arrival Estimation

The synthesis of frequency-scanned monopulse radiation patterns using an array of two leaky-wave antennas (LWAs) is demonstrated. The LWA array must be designed with appropriate shifted frequency-dispersion responses to fulfill the desired monopulse-scanning specification over the required bandwidth and number of channels. This is demonstrated using two manufactured LWAs in half-width microstrip technology, designed to scan in the band from 2.39 to 2.65 GHz covering a field of view (FoV) from -80° to +80° and using three frequency channels. Also, this paper addresses the procedure to estimate the direction of arrival (DoA) of an incoming beacon RF signal composed by prescribed tones distributed in the scanning band. This type of multicarrier beacon signals can be produced in wireless systems which allow for frequency-hopping operation. It is demonstrated that the proposed monopulse DoA-estimation technique combines good angular resolution and wide FoV using a simple passive antenna structure.