Miniaturization techniques of substrate integrated waveguide based on multilayered printed circuit board platform.

摘要

The work in this dissertation starts with reviews and discussions of existing miniaturization techniques for Substrate integrated waveguide (SIW), including ridge substrate integrated waveguide (RSIW), half-mode substrate integrated waveguide (HMSIW) and folded substrata integrated waveguide (FSIW).;In this work, a novel transition between a microstrip line and an SIW in a multilayer substrate design environment is presented. In order to achieve a low-loss broadband response, the transition, consisting of a tapered or multi-sectional ridged SIW and a tapered microstrip line, is modeled and designed by considering both impedance matching and field matching. Characteristic impedance and guided wavelength calculated by using closed-form expressions based on a TRM are used to develop design procedures. Effective broad bandwidth is obtained in two examples developed in this work, which are validated with simulated and measured results. Another three more transitions, including a microstrip-to-SIW transition, a TFSIW-to-SIW transition and an SIW-to-SIW transition, are designed in a two-layer substrate and have good correlation between the simulations and measurements.;Several passive components are designed and fabricated utilizing the miniaturization techniques mentioned above and the proposed transitions. A design procedure of a T-type folded substrata integrated waveguide (TFSIW) hybrid ring is presented and discussed with reference to the calculated parameters of TFSIW transmission lines using TRM. The bandwidth with reference to the return loss at all four ports and isolation between isolated ports is 12.7%, less than -20 dB. The insertion loss and phase difference are -3.7 dB and 180° +/- 3°, respectively, at the center frequency. Two six-port junction circuits based on the HMSIW technique are proposed and implemented over a frequency band from 22 GHz to 26 GHz.;SIW provides a very good solution to integrate a waveguide slot array antenna and its feeding network in a planar substrate. It was found that some miniaturized SIW structures can not only reduce the size of the circuit but also have some features improved, such as impedance bandwidth. A 4 x 4 slot array antenna based on RSIW technique is proposed and an 8.8% bandwidth is easily achieved. With the proposed 2 x 4 TFSIW slot array antenna, the size of the antenna is reduced by 40% and the impedance bandwidth (-10 dB) is 5.6%. Several RSIW arrays are designed with different feeding networks, fabricated in a two-layer Rogers substrate and compared with specifications, such as broadband gain, radiation pattern and return loss. The best design among these array antennas is integrated with an SIW diplexer whose centers of two passing bands are 25.5 GHz and 26.5 GHz, respectively.;In this work, we present two design platforms of SIW phase shifter at 26 GHz, namely an inline phase shifter and a reflection-type phase shifter, for tuning the phase of SIW continuously and digitally, respectively. The diodes are loaded on top of the SIW through some transverse slots opened on the broad wall of the SIW. The tuning range, phase and magnitude imbalance of both inline SIW phase shifter and reflection type SIW short termination are investigated through the correlation between the simulation and measurement. Measured results are in agreement with responses calculated from equivalent models and EM models.;Based on the conclusion drawn from this investigation, an SIW six-port junction that is composed of four 3 dB couplers is built in a single layer Rogers substrate. A transceiver system is proposed using all devices introduced and designed in this work, including -- A phase modulator that is controlled by a sequence of voltage converted from input I/Q signal; -- Two RSIW slot array antennas, with one is placed on the cross-polarized plane of the other; -- An SIW diplexer and an SIW band pass filter; -- A six-port junction whose four outputs are connected with RF power detectors and analog decoder circuits; -- A group of packaged integrated circuits which are surface mounted on the substrate and connected with surrounding SICs through grounded coplanar waveguide (GCPW). (Abstract shortened by UMI.)