Miniaturization Of Microwave Receiver Components

Front-end transceiver is playing an important part in microwave systems. The effort to miniaturize front-end systems has always been a hot research branch. In this thesis a receiver with LTCC ( Low Temperature Co-fired Ceramic ) technology is analyzed and designed to investigate its potential in minimizing the front-end system.First of all, the development of microwave front-end systems and the project which is studied in this thesis, as well as the traits of the LTCC technology, are concisely introduced.Then, the structure of the circuit and why this thesis chosed this idea, as well as how it worked to achieve the goal, were shown in the following chapter. The design of the passive circuit and the active circuit were described. The thesis discussed about the structure of the transition, insulation, inductance and capacitor. Several kinds of embedded miniaturized BPF structures such as Hairpin, Interdiginal, SIR and the LC BPF were designed. The size of the L Band LC BPF is just 4 mm*2.5mm, and the test results show good agreement with the simulation results. A high-quality LNA was concretely described too. The gain of the LNA is more than 14dB and the NF is smaller than 0.8 dB. The miniaturization was well achieved by embedding some inductances into the LTCC material. In the frequency converter circuit, a broadband Direct Quadrature Demodulator with RF and baseband AGC amplifiers.The method for arranging the layout of the whole circuit structure, as well as the measurement results of the front-end, were shown in the fifth chapter. The gain of the receiver is more than 26dB and the NF is smaller than 4 dB. The final output of the frequency converter circuit is 760 mV p-p differential in AGC mode. Analysis of the result was included to show some experiences and the improvments which will be needed in the further research.