Design X‐band monopulse tracking system

In this letter, a higher‐order‐mode coupler using waveguide for multimode monopulse satellite tracking and signal processing schemes handling the signal from the higher‐order‐mode coupler are proposed. The proposed higher‐order‐mode coupler uses TM01 mode for compactness and weight reduction, making it suitable for OTM satellite tracking systems. The TM01 mode is extracted from the two H‐plane slots of the circular waveguide and then divided signals are combined through magic‐T structure. Also, the sum and difference radiation patterns of antenna applicable to monopulse satellite tracking are generated. A monopulse tracking data is extracted using the proposed signal processing schemes to the antenna radiation patterns. The influence of Doppler effect and noise is concerned to enhance tracking accuracy and sliding techniques are adopted to deal with an instantaneous tracking system. Designed X‐band higher‐order‐mode coupler of TM01 mode and signal processing schemes are expected to be used for all OTM monopulse satellite tracking systems.