A High Frequency Resolution Successive-Band Shifted Filters Architecture for a 15-bit IFM Receiver

A novel structure of microstrip-based instantaneous frequency measurement (IFM) receiver is presented in this paper. The proposed structure employs open-ended resonators as the core part of the receiver. Compact frequency-shifted filters are designed to achieve high-frequency resolution, instead of conventional binary division. To overcome the reliability issues that conventional binary division has in high-bit IFMs, we introduce a novel complementary filter design, which leads to a highly reliable and robust system design for IFMs. The proposed structure is simulated by Advanced Design System (ADS) and fabricated on Rogers Ro4003 substrate with 8-mil thickness. There is a good agreement between simulation and measurement results. According to the measurement results, the measured root mean square of frequency error is less than 15 MHz in the S-band. Sensitivity and dynamic range of the proposed receiver are better than -65 dBm and 70 dB, respectively.