Raptor Codes for Super-Dense Networks

Abstract: In this project, we investigate the performance of Raptor codes as candidatesfor channel coding for the wireless communication between access nodes.Very high data-rates are used, and processing uses more resources than transmission.Therefore, we need fast encoding and decoding algorithms for thechannel coding. Raptor codes have linear encoding and decoding times, andcan have very small overhead if they are properly designed. Hence, they arepossible candidates. We have implemented an encoding and decoding algorithm for Raptorcodes, as well as an environment for simulation. The system requirementsare expressed in terms of delay between the beginning of a transmission andthe successful decoding, and storage required during the transmission and processing.We have evaluated the performance of Raptor codes in terms of delayand storage as a function of system design parameters, in particular the numberof nodes in the network, and the size of the packets. We show that if thesize of the packets is properly chosen, Raptor codes can be useful for the application,and we explain the method for choosing the size of the packets. Wealso provide a way to calculate the delay and the storage for a given systemconfiguration, in order for example to determinate the larger number of nodesor the larger of users such that the delay and the storage are acceptable.