The land mobile satellite (LMS) channel is characterised by its relatively long deep fades, especially at higher frequencies like the Ku-band. It would need prohibitively large link margins to overcome this problem by increasing the transmit power. Instead, it is proposed to add an additional layer of coding at the transport layer (transport layer coding) and by spreading the sent packets over time, create an extremely long virtual interleaver. Since the size of files can be in the range of up to some megabytes, an efficient and low complexity encoding and decoding approach is needed. The paper investigates the use of low-density-parity check (LDPC) codes for this purpose.
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