A single-planar integrated self-heterodyne receiver with a built-in beam-steerable array antenna for 60-GHz-band video transmission systems

This paper presents a compact self-heterodyne receiver with a 24-element beam-steerable array antenna using varactor diodes for 60-GHz-band video transmission systems. An MMIC down-converter is integrated with the antenna substrate. The radiation elements of the antenna, are fed in series by a circuit based on microstrip-to-slotline transitions and slotline-to-microstrip transitions. A feed network of the symmetric structure is developed by fully using the in-phase and anti-phase power dividing techniques. In the feed network, variable phase shifters using varactor diodes are inserted to steer the beam direction, and impedance transformers are introduced to increase the steering angle. We fabricated the antenna and measured the antenna characteristics. Furthermore, an MMIC down-converter was mounted on the antenna substrate for a 60-GHz-band self-heterodyne video transmission receiver. The reception performances were evaluated by using a BS (Broadcasting-satellite) digital signal. The antenna gain is about 15 dBi, and the bandwidth is more than 2 GHz. Experimental results show that the antenna is capable of about 16-degree beam steering at 60 GHz. Moreover, in the self-heterodyne receiver, the C/N and BER (Bit Error Rate) patterns can be steered within about 16 degrees by changing the control voltage.