X-band Receiver Front-end Research And Design

Radar was invented for battle in the world war two. It was quickly applied other field. Radar widely used as an all-weather communication obtaining equipment which can detect far distance aim forwardly in national defense and economy. As a part of radar system, the receiver act a important role. As a part of radar receiver, the X-band receive front-end mainly complete the function that translate the weak RF signal from the antenna system to the corresponding middle frequency signal, assure proper dynamic range, low noise figure and STC. Based on the function and technology parameter of the receive front-end, the main results in this paper are as follows:1. Because the input-port of the receive front-end is waveguide, a kind of appropriate transition shape from waveguide to microstrip is selected and designed. The structure and electric dimension is designed by the electromagnetic simulated software(HFSS). The optimal parameter of VSWR and IL is assured by the software.2. This paper analyse compose form and work theory of the limitr, determine some technology parameter of the limitr for the receive front-end.3. This paper analyse work theory and design method of LNA and select a kind of appropriate amplifier.4. This paper analyse work theory and design method of voltage control attenuator and select a kind of appropriate voltage control attenuator.5. By reason of the request for image rejection in receive front-end, there is more 20dB image rejection in mixer. This paper analysis the theory of IRM and design a appropriate IRM for the receive front-end.6. This paper analyse the work theory and design method of filter. Because of the request of receive front-end, the technology parameter of IF filter was confirmed.7. Because of the total request of receive front-end, determine compose form of it, reasonable arrange all components, produce the circuit board.8. Assemble all components, debug and test the whole parameter, acquire a sample.