Σύγκριση μεθόδων

	Κωδικοποίηση Turbo με Επαναληπτική Αποκωδικοποίηση	Κώδικες Ελέγχου Χαμηλής Πυκνότητας (LDPC)	Πολικοί Κώδικες με Αποκωδικοποίηση Διαδοχικής Ακύρωσης
Πεδίο	Τηλεπικοινωνίες	Τηλεπικοινωνίες	Τηλεπικοινωνίες
Οικογένεια	Process / pipeline	Process / pipeline	Process / pipeline
Έτος προέλευσης	1993	1962	2009
Δημιουργός	Claude Berrou, Alain Glavieux, and Punya Thitimajshima	Robert Gallager	Erdal Arikan
Τύπος	iterative error-correcting code	linear error-correcting code	recursive error-correcting code
Θεμελιώδης πηγή	Berrou, C., Glavieux, A., & Thitimajshima, P. (1993). Near Shannon limit error-correcting coding and decoding: Turbo-codes. In Proceedings of the IEEE International Conference on Communications (ICC), 1064-1070.	Gallager, R. G. (1962). Low-density parity-check codes. IRE Transactions on Information Theory, 8(1), 21-28.	Arikan, E. (2009). Channel polarization: A method for constructing capacity-achieving codes for symmetric binary-input memoryless channels. IEEE Transactions on Information Theory, 55(7), 3051-3073.
Εναλλακτικές ονομασίες	iterative decoding, concatenated codes	sparse codes, belief propagation codes	channel polarization, recursive codes
Συναφείς	5	5	5
Σύνοψη	Turbo codes, introduced by Berrou, Glavieux, and Thitimajshima in 1993, are a landmark in channel coding history. They achieve performance within 0.5 dB of the Shannon limit—the theoretical boundary for reliable communication—a feat previously thought impossible with practical complexity. Turbo codes use concatenated convolutional codes with an interleaver and iterative decoding via belief propagation. They were adopted in 3G (UMTS) and remain important in 4G/5G systems alongside LDPC codes.	LDPC codes, invented by Robert Gallager in 1962 and rediscovered in the 1990s by MacKay, are linear error-correcting codes defined by sparse parity-check matrices. They achieve performance within 0.4 dB of the Shannon limit with iterative belief-propagation decoding and have become the standard for modern wireless (WiFi-6, 5G NR, Digital Video Broadcasting). Unlike turbo codes, LDPC codes have a more elegant graph-theoretic structure and more mature theoretical analysis.	Polar codes, introduced by Erdal Arikan in 2009, are the first constructive family of codes proven to achieve the Shannon capacity of symmetric binary-input memoryless channels. They use recursive construction and successive cancellation decoding, a simple greedy algorithm with theoretical guarantees. Polar codes were adopted in 5G NR for control channel coding and are studied for future 6G systems. Unlike turbo and LDPC codes (which are empirical), polar codes provide rigorous theoretical foundations.