The Design And Fabrication Of Microatrip Phased Antenna Array

Due to its high efficiency and flexible beam scanning,Phased array antenna has awide range of applications in wireless communication, radio frequency identification andbusiness car early warning radar,and cause attention and research of many scholars athome or abroad. This paper makes a detailed analysis of microstrip Yagi antenna,microstrip reflection-type analog phase shifte and ARM control circuit, and then esignedand produced a microstrip phased array antenna system,which contains two antennaunits,works in2.4GHz. The test results show that the antenna can steer beam from-20°to+14°continuously.This paper first introduced the design of microstrip Yagi antenna,and then analyzesdifferent size parameters of the influence on the performance of the Yagi antenna, atlast,we Designed two Yagi antennas arranged along the E-surface. The workingfrequency of antennas is2.4GHz.Secondly, this paper has designed a microstrip reflection-type analog phase shiftewith varactor as as its terminal load and a wilkinson power divider. The test results of thephase shifter show that, along with the change of the control voltage, the phase shifter ischanged between75°~165°，the biggest phase shifter is almost up to90°,and insertion lossis in the range of-3.3dB~-4.5dB. The test results that,at the center frequency of2.4GHz,the input and output ports return loss of the wilkinson power dividerare less than-15dB,the isolation between the two output ports is-20dB,and the transmission loss between theinput and output ports is-3.52dB.Then using STM32F103RET6microprocessor as a core part, we designed a hardwarecircuit of the phase shifter. And we wrote a software control interface based on VISUALC++.When we input the required antenna scanning Angle in the software control interface,the hardware circuit can output two road corresponding voltage, and the liquid crystaldisplay the current scanning Angle.Finally, two Yagi antenna, two analog phase shifter,and a Wilkinson power divider aremade in the same piece of medium board, alonge with the hardware control circuit and thesoftware control interface, the phased array antenna system are completed. Mesurement results show that the antenna can be able to steer beam from-20°to+14°at the center frequency of2.4GHz.In this paper, we give the design process of antenna array element, power divider andmicrostrip analog phase shifte and control circuit, the results show that the system isfeasible. But scan Angle range is not wide enough, needs to be further studied.