Study on digital coded technology in active radar calibrator of SAR

The fundamental method of the active coded radiometric calibration technique is analyzed. The theory of reducing the influence of background clutter signal to the precision of radiometric calibration by active coded radiometric calibration technique is explained. Digital coded technique is applied to avoid phase-shifting error of the phase-shifter used in the analog coded method. An experiment is carried out, and the experiment results proved that the active coded radiometric calibration technique can restrain the influence of background clutter signal effectively and improve the precision of radiometric calibration.