Design of Broadband Miniaturized Microstrip Equalizer

The power amplifier module has gain fluctuation in the working frequency band. The ideal solution to this problem, at present, is to add a gain equalizer network to the original transmission network, which is called gain equalizer. In this paper, a miniaturized equalizer using microstrip circuit is designed and manufactured, aiming at the problem that the gain of 2-6 GHz power amplifier module fluctuates greatly. Its working frequency is 2-6 GHz, the balance is about 9 dB, and the input and output standing wave coefficient is less than 1.5, which improves the problem of uneven output power of power amplifier module, and has certain reference value for the research and development of this kind of equalizer. Furthermore, the basic principle of transmission line and gain equalizer and the related design of thin-film circuit are briefly introduced in the paper. According to the actual demand, the target curve is determined, the initial model of gain equalizer is designed. Then the gain equalizer is simulated and optimized by three-dimensional field simulation software, and the 2-6 GHz microstrip gain equalizer is developed. The experimental results of the gain equalizer are in good agreement with the design and meet the design requirements of miniaturization.