Beacon receiver with better power estimation accuracy is the need for the propagation model development for Ka Band propagation studies experiment. This paper proposes the design philosophy of Digital Receiver, signal processing steps & design of window to achieve the beacon power estimation accuracy of +/- 0.5 dB with measurement rate of 1 Hz up to 30 dBHz C/N0 of a single channel Ka-band beacon receiver working with IPSTAR Ka-band on-board beacon. A custom window with intelligent signal processing steps resulted into improved beacon power measurement accuracy of +/- 0.5 dB over a large programmable bandwidth which is better than the available beacon receiver developed so far under similar signal conditions. A performance comparison with different window functions is also presented. The present receiver design works in closed loop with L-band downconverter to achieve better power estimation accuracy and suitable for unmanned operation. The designed receiver is tested within lab setup with simulated input and also tested in field with 20.199827 GHz beacon onboard IPSTAR. © 2013 IEEE.