Vertaile menetelmiä

	Nollatukahdutus- ja minimikeskineliövirhe-ekvalisaatio	LDPC-koodit (Low-Density Parity-Check Codes)	Ortogonaalinen taajuusjakoinen multipleksointi (OFDM)
Tieteenala	Tietoliikennetekniikka	Tietoliikennetekniikka	Tietoliikennetekniikka
Menetelmäperhe	Process / pipeline	Process / pipeline	Process / pipeline
Syntyvuosi	1974	1962	1971
Kehittäjä	Saleh Mansour and Paul Zervos	Robert Gallager	Weinstein and Ebert
Tyyppi	linear equalization algorithm	linear error-correcting code	multicarrier modulation scheme
Alkuperäislähde	Proakis, J. G. (2001). Digital Communications (4th ed.). McGraw-Hill.	Gallager, R. G. (1962). Low-density parity-check codes. IRE Transactions on Information Theory, 8(1), 21-28.	Weinstein, S. B., & Ebert, P. M. (1971). Data transmission by frequency-division multiplexing using the discrete Fourier transform. IEEE Transactions on Communication Technology, 19(5), 628-634.
Rinnakkaisnimet	channel equalization, interference cancellation	sparse codes, belief propagation codes	multicarrier modulation
Liittyvät	5	5	5
Tiivistelmä	Zero-Forcing (ZF) and Minimum Mean-Square Error (MMSE) equalization are fundamental linear receiver algorithms for combating intersymbol interference in dispersive channels. Developed in the context of data transmission theory, these methods form the basis of modern channel equalization in wireless and wired systems. While ZF aggressively cancels interference, MMSE balances interference suppression with noise enhancement, making it the optimal linear solution under Gaussian noise.	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.	OFDM is a multicarrier modulation technique that divides a wideband channel into many narrowband orthogonal subcarriers. Introduced by Weinstein and Ebert in 1971, it exploits the duality between time and frequency domains to efficiently use spectrum while mitigating intersymbol interference in frequency-selective channels. OFDM is now the standard for high-speed wireless systems including WiFi, cellular LTE, and digital broadcasting.