Design and optimization of a parallel-coupled microstrip bandpass filter for Software Defined Telescope is presented in this paper. The simulation and optimization is done using ADS and Momentum. The filter is designed and optimized at a center frequency of 1.42GHz. The filter is built on a relatively cheap substrate FR-4 with permittivity 4.4 r and loss tangent tan 0.02 . Simulation results reveal that the filter operation is optimum over the frequency range 1.41 GHz to 1.44 GHz. The 3 dB bandwidth is thus 300 MHz. the return loss is below -10 dB over the passband. Insertion loss is -2.806 dB in the passband. The filter is almost matched to the characteristic impedance ( Z0 ), 50 Ohms. Also it is observed that the phase varies linearly with frequency. The filter once fabricated could be used at the radio receiver of the Software Radio Telescope to filter out terrestrial radio interference.
J. Rajendran, K. P. Soman, and Peter, R., “Design and Optimization of Band Pass Filter for Software Defined Radio Telescope”, International Journal of Information and Electronics Engineering, vol. 2, pp. 649-651, 2012.