Designing an S Band Receiver for LEO Applications

In this paper we describe a generic receiver as a single channel S-band receiver and it is composed of two modules. The first module (down converter) consists of an input band pass filter, LNA, image rejection filter and down-converter with a PLL local oscillator. The second module consists of the IF module derived from the VHF receiver. The IF module consists of a low pass filter, 20MHz band pass filter, a LNA, narrow band pass filter and FM receiver IC with associated circuitry. The number of S-Band Receivers to be flayed on the LEO microsatellite is the main issue here. It is safer to include two (02) receivers as dual redundancy because it is the minimum requirement and the best option in terms of risk against cost and complexity. The study here is concentrate on the design and test results of an S-band receiver which receive commands and software from Earth.