부산대학교 도서관

An instantaneous frequency measurement (IFM) module with 2000MHz instantaneous bandwidth was designed and fabricated. The classical interferometer phase-comparison is adopted and the delay line element in the microwave correlator is realized based on the stripline. The results show that compared with coaxial line and microstrip line, the stripline has good electromagnetic compatibility and producibility simultaneity. Firstly, this paper introduces the application of IFM receiver, gives the common methods of frequency measurement and then interferometer phase-comparison IFM is mainly studied. The scheme of the proposed module is given and the design of stripline delay line is described in detail. Some techniques such as serpentine routing and matching via are used to improving the microwave performance. The input and output return loss is less than -20dB within the operating frequency range for the interconnection of stripline and microstrip. Finally, the proposed IFM module realizes the frequency measurement accuracy up to 2MHz with 10-bit digital coding within 2000MHz bandwidth. And during the dynamic range of input power from +10dBm to -70dBm, the maximum frequency error is ±8MHz. Frequency measurement time is less than 150ns and the operating temperature range from -45℃ to +70℃. The specifications and performance of the proposed IFM module can meet many defense application requirements. It permits production of lightweight, modular, ruggedized and low cost systems that provide highly accurate instantaneous frequency measurement capability and high system sensitivity which allows for excellent detection ranges to accomplish the mission.