6.972 PRINCIPLES OF DIGITAL COMMUNICATION II Fountain Codes
نویسندگان
چکیده
3 Tornado Codes 5 3.1 Code Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 3.2 Optimal Degree Sequences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 3.3 Practical Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 3.3.1 Matlab Implementation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
منابع مشابه
Trapping Sets in Fountain Codes over Noisy Channels
Fountain codes have demonstrated great results for the binary erasure channel and have already been incorporated into several international standards to recover lost packets at the application layer. These include multimedia broadcast/multicast sessions and digital video broadcasting on global internet-protocol. The rateless property of Fountain codes holds great promise for noisy channels. The...
متن کاملLecture 4 — September 17 4.1 Digital Fountain Characterization 4.1.1 Limitations of Building Digital Fountain with Rs Codes
A Digital Fountain is an approach used to provide reliability in multicast networks without the use of receiver initiated packet retransmissions. Prior work to Digital Fountain has shown that use of receiver initiated retransmissions to recover lost data is unscalable in multicast networks and the impact is significant in lossy networks. Instead, like many other techniques that transmit redunda...
متن کاملIRWIN AND JOAN JACOBS CENTER FOR COMMUNICATION AND INFORMATION TECHNOLOGIES On-Line Fountain Codes with Low Overhead
An on-line fountain code is defined as a fountain code for which an optimal encoding strategy can be found efficiently given any instantaneous decoding state. This property is important for data distribution in practical networks. In this paper we formalize the problem of on-line fountain code construction, and propose new on-line fountain codes that outperform known ones in having factor 3-5 l...
متن کاملDigital Fountain Codes System Model and Performance over AWGN and Rayleigh Fading Channels
Digital fountain codes were originally packet-level forward erasure codes, but researchers have found that they are good at correcting bit errors. Modern LDPC and turbo codes have been shown to approach the Shannon limit. However, they are fixed rate codes and cannot well satisfy the Internet services that may encounter variable loss rates or asynchronous data access. For both packet and bit le...
متن کاملLinearly-Coupled Fountain Codes
Network-coded multiple access (NCMA) is a communication scheme for wireless multiple-access networks where physical-layer network coding (PNC) is employed. In NCMA, a user encodes and spreads its message into multiple packets. Time is slotted and multiple users transmit packets (one packet each) simultaneously in each timeslot. A sink node aims to decode the messages of all the users from the s...
متن کامل