A V-band single-chip MMIC oscillator array using a 4-port microstrip patch antenna

In this paper, a V-band strongly-coupled single-chip MMIC oscillator array is presented. To reduce the MMIC chip size and increase the output power of the millimeter-wave source module, the output powers of the four oscillators are combined in a single chip using a four-port patch antenna. A parallel combination of the two pairs of the oscillators operating in a push-pull mode was implemented using a single four-port patch antenna. When measured in a closed over-sized waveguide, the circuit showed the output power of 3.8dBm at 60.626GHz. The measured radiation pattern of the active antennas array in free space shows broadside pattern with low cross-polarization level, verifying that the current profile on the antenna closely follows that of the ideal push-pull mode. The proposed active antenna approach is a promising candidate for a low-cost source module at mm-waves.