Waveguide-based antenna arrays in multi-chip module technology

For mm-waves, two types of low-loss waveguide are analysed, designed and measured. One is the hollow substrate integrated waveguide (HSIW) in which the inner dielectric of a traditional substrate integrated waveguide (SIW) is removed to resemble the propagation characteristics of a standard rectangular waveguide (RWG). The measured attenuation of a WR28-like HSIW is 2 Np/m or 17 dB/m throughout the Ka band. The second is the dielectric insular image guide (DIIG) in which an insular layer is added between the dielectric and the metallic ground to further reduce the conductor loss. The measured attenuation of a Ka band DIIG is 26 dB/m at 35 GHz. Based on the two waveguides, two high-gain antenna arrays operating in the Ka band are designed and measured. One is a 6 x 6 slot antenna array, centrefed by the HSIW. The Taylor-distribution technique is applied in two orthogonal directions to suppress the sidelobe level. The measured gain of this antenna array is 17.1 dBi at the centre frequency of 35.5 GHz. The other is a double-sided 10- element dielectric insular resonator antenna (DIRA) array, end-fed by the DIIG. The Taylor-distribution technique is also applied here to achieve a gain of 15.8 dBi at the centre frequency of 36 GHz. The great potential of these high-performance antennas is that they can be integrated with other microwave components (filters, power amplifiers, etc.) to form a complete front-end or transceiver in multi-chip module (MCM) technology.