Wide dynamic range microwave attenuator and driving circuit

Multi-stage pin diode is widely used in microwave attenuator and switch. In this paper, the relations between microwave attenuator characteristics and PIN diode spaces for a multi-stage attenuator are analyzed theoretically. According to theoretical results, a high performance wide dynamic range, broadband microwave attenuator, its band extends from 3.2 GHz to 26.5 GHz, is designed. In order to make it maintain good linearity in the whole power adjusting process, an exponential driving circuit is also designed. After the design is applied in microwave vector network analyzer for experiment, the results show that the dynamic range of the attenuator can reach about 70 dB, and the linearity is within ±1 dB.