A Diversity Receiver-Based High-Gain Broad-Beam Reception Array Antenna

A novel reception antenna configuration is proposed for achieving high gain and broad beam coverage at the same time. This is accomplished by combining a multibeam array antenna with a diversity receiver. Signals from different beams are merged by diversity receiver in the baseband level using the maximal ratio combining scheme. The proposed approach is implemented by integrating a dual-channel digital TV receiver, a four-dipole array, and a 4 x 4 Butler matrix. Two outputs of the array, which have beam maxima pointing away from the boresight by +/- 14 degrees, are connected to the two receiver inputs. Sensitivity measurements are conducted for different incident angles to find lowest transmitter power levels permissible for DTV signal demodulation. Measured results of a reference single-beam antenna validates that its angular sensitivity profile is proportional to the antenna gain pattern, and the ones of the diversity receiver-based array confirm that the proposed method can combine receptions of the two beams coherently. The effective 3 dB beamwidth of the implemented antenna is doubled, and the gain maximum is comparable with the single-beam array.