Small-aperture, high-resolution beam-scanning antenna array using nonlinear signal processing

A high-resolution two-element antenna array is demonstrated using nonlinear signal processing of the output signals of the two antennas. The basic principle of this method is to convert the output signal of each antenna into a train of very short pulses and to extract a time delay between the two pulse trains by correlation. Compared to previous work, the input signals in this work are first down converted to a low IF frequency and then a nonlinear signal processing can be achieved using fast digital ICs. An experimental receiver was built, and the general principle of the new approach is demonstrated. In addition, including digital delay ICs into each channel, even beam scanning is included. Adding a transmitter with a FM-modulation, a simple radar sensor was built up.