Polarized Antenna And A Transition Structure Research Based On LTCC Millimeter Round

LTCC (Low-Temperature Co-fired Ceramic) is very suitable to be used in investigation of millimeter wave band due to its high performance in millimeter wave such as high thermal conductivity, low medium loss, high QT, etc. The multi-layer advantage of LTCC technique provides the benefit for the designer, which can integrate passive components and antenna at3D structure, so as to create more advantageous conditions for miniature structure. This thesis is mainly concerned with the design of circularly polarized antennas and arrays in millimeter wave band, the passive components on substrate integrated waveguide, as well as the implementation of waveguide-to-microstrip and waveguide-to-stripline transition. The author’s major contributions are outlined as follows:1. A circular polarized antenna in3mm band on LTCC and its4-element planar array are investigated. First, scheme of the common LTCC helical antenna in3mm band is verified. And then, a new LTCC helical antenna with pattern correction is designed and processed. The researches of the measured results have been done. Finally,4-element planar arrays with different feed methods are presented, and the comparisons of different feed methods are discussed.2. The passive components on substrate integrated waveguide in3mm band have been investigated. T-shaped power divider and transition structure from top layer to down layer are presented respectively. It turned out that the impedance bandwidth of the return loss which is less than-15dB can be achieved33%for the T-shaped power divider. And the bandwidth of transition structure from top layer to down layer can be achieved33%.3. Waveguide-to-microstrip and waveguide-to-stripline transition in Q band have been investigated. The vertical transition structures of waveguide-to-microstrip and waveguide-to-stripline are designed using LTCC technology. Meanwhile its analysis is presented. Results show that waveguide-to-microstrip transition can realize23%impedance bandwidth of the return loss which is less than-15dB and11%impedance bandwidth of the return loss which is less than-25dB. Within the23%impedance bandwidth, the insertion loss is less than0.5dB. And waveguide-to-stripline transition can realize23%impedance bandwidth of the return loss which is less than-15dB and11%impedance bandwidth of the return loss which is less than-25dB. Within the23%impedance bandwidth, the insertion loss is less than0.5dB.