Researches On High Gain And Miniaturization Of Log-periodic Antenna

With the progress of the society and the development of science and technology, wireless communication technology has become the pillar industry in today’s society. The antenna is a microwave component in wireless communication system to receive and transmit radio waves, it’s performance fit or unfit quality affects the quality of communication directly. In recent years, based on the communication system of channel capacity, information transmission rate and energy radiation efficiency, and military surveillance and monitoring requirements, wide band, miniaturization and high gain antenna and it’s important significance of the research.Log Periodic Dipole Antenna(LPDA) is not a member of the frequency change of antenna was developed in 1950s. Because of it’s simple structure and excellent performance and itself inherent wide-band characteristics antenna, it has been used widely. Therefore, research on the characteristics of miniaturization and high gain LPDA has very significance and application prospect.Because the micro-strip LPDA has similarity on the working principle with LPDA, in this article, through analyzing the working principle and structure size of LPDA for the good bedding of the design of micro-strip LPDA. Correct the relevant parameters from the log-periodic antenna to the micro-strip log-periodic antenna, the lpda, and with the aid of the electromagnetic simulation software Ansoft HFSS13.0 modeling, simulation and optimization of antenna. First of all, through the LPDA parameter correction work designed a 1.5GHz-6GHz conventional micro-strip log-periodic antenna. Then, through to the antenna vibrator fold, the top load andtilt of the dipole method to design the two work in 1.5GHz-6GHz mini micro-strip log-periodic antenna, the two antenna had a very big size reduction, realize the miniaturization of micro-strip LPDA design requirements. To the requirement of LPDA high gain, this paper is implemented by means of set of array. Group for antenna array demand dof feed network, Wilkinson power splitters and impedance converter is presented in this paper the basic principle, adopt the method of multiple class impedance converter cascade to expand bandwidth, power splitters work using ADS2008 electromagnetic simulation software designed a work at 1.5GHz-6GHz frequency ultra-wideband Wilkinson power splitters.In this article, through Ansoft HFSS13.0 and Agilent ADS2008 software simulation was carried out on the log-periodic antenna and power splitters design, according to the results of simulation, and make related physical processing and make tests. Results show that within the scope of the band, conventional micro-strip LPDA gain reached above 6 dBi. Ultra-wideband Wilkinson power splitters return loss is greater than 10 dB; Two new miniaturized micro-strip LPDA gain in more than 5 dBi, compared with the conventional micro-strip LPDA lateral size shrank by 29.86% and 29.86% respectively; Antenna array gain more than 10 dBi. Basic satisfy the design requirements of the antenna above indicators, to verify the feasibility of miniaturization and high gain technology in this paper.