Research On K-band T/Rmodule And Antenna Arrays

Nowadays active phased array has already been an amazing development in radar system. With the rapid advancement of the digital integrated circuit technology and power amplifying device, the research for the active phased array technology is becoming much more important, including the array technology and the T/R module technology. T/R module, which located between antenna and power divider network, is the key part of the active phased array. Using it, the microwave signal can be shifted, attenuated and amplified. In the radar system, T/R module and the antenna unit are correspondence. Therefore it’s extremely significant to fulfill the miniaturization of the T/R module. Using the LTCC technology in the manufacture of the phased array antenna and the T/R module, miniaturization can be realized, so do the high density, reliability, and low cost.Based on the LTCC technology, the manufacture of the eight channels T/R module has been realized in this thesis, so do the miniaturization and the highly integration. The overall design of the whole system as follows, cascading the driven amplifier and the power amplifier in the transmitting branch design, maximum output power can be guaranteed; cascading two identical low noise amplifier in the receiving branch, both the branch gain and the system noise figure can be optimized. By introducing the outer control signal, the microwave signal has been shifted and attenuated. With this, the scanning of the antenna beam have been realized.In this thesis, a few kinds of phased array antenna units have been designed and realized. The stacked patch and surface meander technology have been utilized in the design of the micro-strip antenna, which largely improve the relative bandwidth of the antenna from 4% to 15%. In the design of the tapered slot antenna, a slotted surface has been introduced, which completely change the surface current distribution of the patch, to raise the antenna gain from 4.8d B to 5.4d B. Afterwards the antenna array has been designed and realized. Applying the algorithm of Taylor weighted distribution, the sidelobe level has been improved, which less than 20 d B within ±30°scanning angle range. By changing the phase difference of the antenna elements, the beam scanning has been achieved.