Hermetically Sealed S-Band LTCC Based Transmit/Receive Module with Integrated Self-Calibration Circuitry for Space-borne SAR

This paper presents the design and measured results of a hermetically sealed Low Temperature Co-Fired Ceramic (LTCC) based Transmit/Receive (T/R) module with integrated self-calibration circuitry for S-Band Synthetic Aperture Radar with Digital Beam Forming on Receive. Real-time digital beam forming mandates high precision digital calibration of each channel independently, necessitating integrated self-calibration circuitry inside each T/R module. Across 70 developed LTCC T/R modules, transmit linear gain> 39 dB, transmit output P
1dB
> 28 dBm, receive gain> 60 dB and noise figure < 1.6 dB has been achieved. Excellent calibration performance in terms of leakage signal isolation, > 80 dB during transmit calibration and> 110 dB during receive calibration, has been realized across modules. To the best of our knowledge, T/R modules on LTCC technology with integrated calibration circuitry having high isolation during both transmit and receive calibration has not been reported.