Design of LDPC codec for the FX.25 pico-satellite link

Abstract

In this dissertation, a novel Weighted Bit-Flipping (WBF) Low Density Parity Check (LDPC) decoder known as the Reliability Ratio-Based Self-Normalized WBF (RRSN-WBF) decoder is proposed. This proposed decoder is compared to the latest WBF decoders examined in the literature. Along with this decoder an encoding method with low complexity is also used. The encoding method used is the Richardson and Urbanke Upper Triangular encoding method. The RRSN-WBF decoder and Richardson and Urbanke encoding method are used to aid the University of Malta satellite radio project known as the UoMBSat1 whose aim is to launch a pico-satellite. To aid in the design of the communication system of this UoMBSat1 project the current available technologies for nano/pico-satellite systems which consider a SDR system were examined. During this examination special attention was given to the type of FEC and data-link protocols these systems used. In this project, the AX.25 and FX.25 protocols were implemented. The aim was to show that LDPC codes can also be integrated with the FX.25 protocol. This was successfully achieved. Based on this implementation various analysis concerning the integrated LDPC codes with the FX.25 protocol are outlined.