Uporedite metode
Pregledajte izabrane metode jednu pored druge; redovi koji se razlikuju su istaknuti.
| Kodovi sa niskom gustinom provere pariteta (LDPC)× | Višestruki ulaz višestruki izlaz (MIMO)× | Ortogonalna multipleksacija podele frekvencije (OFDM)× | |
|---|---|---|---|
| Oblast | Telekomunikacije | Telekomunikacije | Telekomunikacije |
| Porodica | Process / pipeline | Process / pipeline | Process / pipeline |
| Godina nastanka≠ | 1962 | 1995 | 1971 |
| Tvorac≠ | Robert Gallager | Telatar, Foschini, and Gans | Weinstein and Ebert |
| Tip≠ | linear error-correcting code | spatial multiplexing technique | multicarrier modulation scheme |
| Temeljni izvor≠ | Gallager, R. G. (1962). Low-density parity-check codes. IRE Transactions on Information Theory, 8(1), 21-28. DOI ↗ | Telatar, I. (1999). Capacity of multi-antenna Gaussian channels. European Transactions on Telecommunications, 10(6), 585-595. DOI ↗ | 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. DOI ↗ |
| Drugi nazivi≠ | sparse codes, belief propagation codes | spatial multiplexing, antenna diversity | multicarrier modulation |
| Srodne | 5 | 5 | 5 |
| Sažetak≠ | 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. | MIMO is a technique that uses multiple transmit and receive antennas to significantly increase channel capacity and reliability. Pioneered theoretically by Telatar (1999) and Foschini & Gans (1998), MIMO exploits multipath propagation—typically a liability in wireless—as an asset by creating independent spatial channels. It is now fundamental to all modern wireless systems including LTE, WiFi-6, and 5G, where it provides both capacity gains through spatial multiplexing and robustness through diversity. | 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. |
| ScholarGateSkup podataka ↗ |
|
|
|