Narrowband frequency scanning array antenna at 5.8 GHz for short range imaging

We present a frequency scanning array antenna for radar applications. A high angular range is obtained while requiring only a small frequency band. This is achieved by using a band-pass filter feed structure that increases the frequency-dependent phase difference between the individual array elements. An angular range of ± 50 degrees is obtained while using only 150 MHz bandwidth with 5.8 GHz center frequency corresponding to the ISM Band. This antenna type can be applied for detecting covered objects or for short range imaging.