Microwave And Millimeter Wave Filters Based On Ltcc Technology With L-band Transceiver Front-end

LTCC (Low-Temperature Co-fired Ceramic) technology makes use of a multi-layer construction to form a hermetical, high-density substrate. With this feature, it can improve the performance of the circuits, reduce the volume and decrease the weight of the system. L-band transceivers stand a key role in communication, radar, and some other microwave systems, thus the effort to minimize and higher the performance is a hot research branch for related engineers and scientists. Under this background, the focus of this thesis, microwave and millimeter-wave bandpass filers and an L-band transceiver with LTCC technology, is meaningful.Firstly, a brief introduction to LTCC technology and its corresponding components and systems are laid out to help the viewer a better understanding for the background of this thesis. For the convenience of the latter work, some inter-connectors and transitions, such as Ms-SL (Microstrip-Stripline), Ms-SIW (Microstrip-Substrate Integrated Waveguide), and etc, are designed. Meanwhile, a new Ms-RW (Microstrip-Rectangular Waveguide) transition is proposed, which adoptes a SIR-type (Step Impedance Resonator) opening to broaden the bandwidth and to simplify the construction. Then, the work to embed microwave and millimeter-wave filters is introduced. Through the transformation from K/J transformers to L/C circuits, prototypes of two-pole narrow bandwidth band-pass filters with targeted zeros are synthesized; an L-band L/C filter is designed with 3-D electromagnetic simulation software to validate this method. What is more, waveguide and cavity type filters based on SIW constructions are designed. Based on the knowledge of this work, a new DFSIW (Derivative Folded Substrate Integrated Waveguide) resonator is proposed. The DFSIW resonators is formed by doubly or even multiply folding the traditional SIW resonator, so that they have the merits of compact size and compressing some higher-order modes (which would be helpful for out-of-band rejection for band-pass filters). Besides, work on the general Chebyshev coupling matrix makes a three-pole FSIW filter of three transmission zeros possible. This thesis also casts some interest on the dual-mode filter design for its potential of improving filter performance and reducing the size. Ka-band patch-type and cavity-type dual-mode filters are designed; what is more, a dual-mode working FSIW cavity filter is proposed for the first time. Finally, this thesis aims to design the L-band transceiver with the help of previous work.The module size of the L-band transceiver is 59×59×18mm~3. A double frequency conversion schematic is designed to depress the imagine frequency. To reduce the size, the receiver and transmitter use common LOs. The mearured results is that the transmitter fails to reach the targeted function, for the failure caused by the IF filter embeded in the LTCC substrate; the receiver has a gain within 21±1dB, image rejection larger than 30 dB and noise figure about 12dB.