Ka-band Receiver Front-end Design

In microwave and millimeter-wave systems, the receiving front-ends play critical roles for the whole system performance. The theory and design for Ka-band low noise integrated receiving front-ends are discussed in this thesis.The characteristics of millimeter wave, microwave and millimeter wave devices and integrated circuits are discussed in Chapter 1. The development of the front-end at home and abroad as well as the uses and technical requirements of this subject are introduced. Based on the principle and main technical indicators of Radar receiver, the circuit diagram of low noise receiving front-end and the estimates of preliminary indicators were given.Passive circuit relevant to our subject is discussed in Chapter 2. Firstly, we introduced the structures of several common waveguide - microstrip transition, and the waveguide - microstrip transition structure used in this subject was simulated and tested. Then some methods of the image rejection were discussed and analyzed, and the needed method of frequency suppression was decided, and simulated.The major indicators like the noise factor, conversion loss and dynamic range are detailed in Chapter 3. The working theories of single-ended mixers, single-balanced mixers, double-balanced mixer and harmonic mixer are discussed. The needed mixer chip was chosen according to the actual circumstances .Then the noise figure, dynamic range, power gain, and other key indicators of small-signal amplifier are presented in Chapter 3. Two kinds of low-noise amplifier chips were introduced, and the amplifier structure used in this subject was selected through the comparison of the both.In Chapter 4, a Ka-band low-noise receiving front-end is achieved based on the discussions of the aforementioned various functional components. According to the technical requirements of this subject, the design scheme of the receiving front-end was given. The manufacture, assemblage, and the test of the receiving front-end are expounded separately. The test data indicate that the Ka-band low-noise front-end developed in this thesis fully meets the required indicators and of which noise, gain, image suppression ect. are much better than requested. In this paper, the millimeter-wave receiving front-end is achieved by the combination of various functional components, which are based on the technology of hybrid integrated circuit and the conversion of a 35GHz±800MHz RF signal to a 1.6GHz±800MHz IF signal is accomplished. The manufactural method is verified and the chip is tested. The Ka-band receiving front-end proposed in this thesis fully meets the technical requirements in all indicators. And it is convenient to make certain simple modifications of the proposed millimeter-wave receiving front-end to meet the demand of various indicators, if the requested characteristics are close to the requirements in this thesis.