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This paper presents X-Band wide bandwidth coaxial cavity band pass filter for spacecraft checkout applications. Mostly coaxial cavity filter is used for designing narrow bandwidth filter, less than 1 percent bandwidth but in this paper an attempt has been made to design and develop a compact size filter with more than 1 percent bandwidth. The main advantage of this designed filter is its wide bandwidth and excellent harmonic rejection performance. The realized filter has 1.1 dB insertion loss at center frequency of 8.2 GHz, better than 18 dB return loss over a passband of 7.96 GHz to 8.44 GHz and 60 dB rejection at 720 MHz away from center frequency. Achieved results of proposed filter are in good agreement with the design specifications.

SAR payloads are generally used on-board all-weather imaging satellites. When compared to optical payloads they are found more suitable for target detection applications in absence of sunlight. Their working principle is based on transmission and reception of pulses of predefined pulse characteristics. The reflected pulse from earth terrain is analysed and processed based on the changes in the transmitted pulses. This analysis provides all the necessary information regarding the terrain. The effectiveness of the image generation depends on the accuracy of the desired pulse that is transmitted. Thus there is a need for characterizing the transmitted pulses for all the relevant parameters. This paper provides an automated scheme to characterize the transmit receive modules in a typical LFM (Liner Frequency Modulation) SAR payload. This scheme includes a test set up comprising of various COTS measurement instruments. It also includes an automation software which conducts all the measurements using the test set up and presents the results in a standard form.