Design and analysis of ultra-wide band and millimeter-wave antennas

Abstract

Ultra-wideband (UWB) antennas and 60-GHz millimeter-wave antennas and arrays are analyzed and designed in this thesis for developing high-speed short-range wireless communications.

Firstly, a probe-fed crossed circle-disk monopole UWB antenna with stable omnidirectional radiation pattern was studied. The antenna was then cut by half to form a crossed semi-circle monopole antenna with a top-loaded patch to reduce its height. Moreover, a new crossed semi-ring band-notch UWB antenna with L shaped slots was developed.

Secondly, an effective equivalent circuit for a UWB antenna was proposed for possible co-designing with analog/digital integrated circuits in the time domain by using a new automatic physical augmentation with tuning method. The proposed method has been validated for modeling a spiral inductor and an MIM capacitor in a wide bandwidth.

Next, a new compact and multilayer UWB planar antenna was designed using the low temperature co-fired ceramics (LTCC) technology, which gives the possibility of integrating RF circuits and antennas in a single substrate. The configuration of the proposed multilayer UWB LTCC planar antenna fully exploits the three-dimensional (3-D) integration feature of the LTCC technology and explores a new way for antenna size reduction.

Lastly, novel 60 GHz integrated antennas and arrays using the LTCC technology were developed. A new wideband planar circularly polarized helical antenna array was designed and realized in LTCC. Moreover, a wideband LTCC aperture-coupled truncated-corner circularly polarized patch antenna with a sequential rotation feeding scheme was proposed in the 60-GHz band. The wire-bonding packaging technology with a T-network compensation was also studied in the 60-GHz band. Development of an active circularly-polarized antenna by integrating the antenna array with a low noise amplifier in LTCC was demonstrated to enhance the receiving power.