چکیده (انگلیسی):

Abstract: Luby Transform (LT) codes, the first realization of
rateless codes are widely used in wireless communication mainly for
its adaptability to varying channel conditions and its capacity
approaching performance. In spite of the above advantages and its
simplicity in implementation, LT codes suffer from a bottle neck of
premature termination due to the poor design of degree distribution.
In this study, a novel degree distribution called Joint Degree
Distribution (JDD) is proposed for the successful completion of LT
encoder/decoder processes. The efficient utilization of the bandwidth
is tried to be achieved by using only ‘k’ encoded symbols for ‘k’
source symbols, unlike in traditional systems. JDD is carefully
designed to ensure that the encoding/decoding delay does not exceed
that which is existent in the traditional systems. The performance of
JDD for throughput and bit error rate, experimented over Additive
White Gaussian Noise (AWGN) channel compared to conventional
degree distribution was observed to be much better.