Research And Design Of High Isolation And Dual-polarization Antenna

With the development of the communication systems, the use ratio and the quantity ofinformation attract more and more attention. Therefore, the study of the dual polarization antennasbecomes hotspot. For the dual polarization antennas, the small volume and light weight is themainly study direction. The microstrip dual polarization antennas become the research key point.This paper presented a single layer microstrip dual polarization antenna and its performanceanalyze.To improve the isolation of the dual polarization antennas, a highly isolation dual polarizationmicrostrip antennas with corner fed is proposed. The two radiation patches are the square patches,and fed in serial form in the corner. The operating range of the antenna is from5.66GHz to 5.74GHz.The size of this antenna is 22mm×22mm×1mm. This antenna can provide a better E-plane andH-plane radiation pattern, also with a better gain. The high frequency structure simulator HFSS isused to analyze and optimize the parameters which can influence the performance of the antenna.On this basis, the antenna is fabricated and measured with vector network analyzer. The simulatedand measured results show that this antenna can meet the requirements of highly isolation and dualpolarization.A dipole antenna is also designed in this paper. To realize the performance of the highlyisolation and dual polarization, the antenna is a single layer microstrip antenna. Firstly, the singlemicrostrip dipole antenna is designed and achieved the bandwidth of 5.15GHz-6.0GHz. Acommonly dipole antenna can not meet the bandwidth requirement. Through inserting a microstriptransmission line in two single dipoles, a broadband microstrip dipole antenna can be achieved.Secondly, the DGS(defect ground structure) is added in the dipole antenna. The operating frequencyrange of the antenna can be adjusted through changing the size of the DGS. Thirdly, the influence ofantenna size to the operating frequency is discussed. Through placing two single dipoles crossly, adual polarization antenna is achieved. Then the influence of the two dipoles placed position to theperformance of the antenna is studied. Fourthly, the feed network is added to this dual polarizationantenna and the simulated results by HFSS are obtained. The two antennas are fabricated andmeasured. They are in good agreement. Finally, the drawback of the two antennas is discussed andalso the research direction in the future is supplied.As a word, this thesis puts forward two section of monolayer bipolar microstrip antenna strips.Through the comparison of two models of antenna that, microstrip antenna oscillator realize twopolarization has a wide bandwidth and good isolates degree, after the double polarized antenna to study as a reference, therefore has the engineering application value.Finally, the paper discusses the two paragraphs of the antenna that exist deficiencies and thefuture research direction.