Reseach And Design Of Ka/Ku Band Transceiver RF Front-End

With the progress of science and technology, the application fields and technical performance of wireless system have made great progress which includes wireless communication system and radar systems. The performance of RF front-end of wireless system has a direct impact on the performance of the whole system.This paper first introduces the design of the Ka/K band multi-channel receiver. As a result of using time-sharing in this receiving system, this work make three information channels in a receiving channel, which change information channel by changing the local oscillator’s operating frequency and this method simplify the design and reduces the design cost. The receiver adopts double-conversion superheterodyne structure.ADS(Advanced Design System) and HFSS(High Frequency Structure Simulator) software simulation was carried out on the front suppression filter design in the receiver, and the two separate frequency conversion module design. Finally, within 300 MHZ intermediate frequency bandwidth, all three receiving information channel of the receiver has 45 dB gain which is 30 dB controlled with 1dB step and the noise figure is better than 8 dB and image rejection is excellent. The output intermediate frequency is 720MHz±150MHz.Moreover, this paper introduces the RF front-end design of a TDOA radar system. The work focuses on the communication front-end design of the sub-system.and the front end contain three information channels. The volume restriction is severe,which make all the three information channel can only be integrated in a semicircle cavity which’s diameter is only 160 mm and made us have to use coaxial-cable to connect different part of the front end. The entire three information channels adopt double-conversion superheterodyne structure and share antenna by using a circulator and a duplexer. Finally, we have +27d Bm output power in 5MHz bandwidth around 16 GHz and-5dBm output power in 150 MHz around 15.35 GHz. The reception channel has a 60 dB gain in 5MHz around 16.7GHz; the noise factor(NF) is less than 9.5dB. In addition to the work above, we design a 4-way power divider work in Ku band and an equalizer which operate between 2 and 18 GHz.