Resolution enhancement in antenna pattern measurements using pulse modulated averaging technique

This paper studies the improvement of Earth station antenna pattern measurements in a satellite communication system by increasing the resolution of the measurement. The objective is to devise a data acquisition algorithm, which improves the dynamic range of the measurement; and requires minimal modifications to the ground station setup utilizing readily available equipment. The proposed approach improves the conventional measurement techniques by utilizing pulse modulation of the test signal amplitude and its synchronous detection. The noise floor in the pattern is reduced by biasing out the average noise power calculated during the off cycle of the pulse. In addition, the randomly fluctuating local mean in the receiver output is reduced. Experimental results show improvements of over 10 dB in the dynamic range of the antenna pattern.