Сравнение методов
Просматривайте выбранные методы рядом; строки с различиями подсвечены.
| Множественный доступ с контролем несущей и предотвращением коллизий (CSMA/CA)× | Многовходовая многовыходная система (MIMO)× | Ортогональное частотное мультиплексирование (OFDM)× | Протокол случайного доступа с разделением по времени Slotted ALOHA× | |
|---|---|---|---|---|
| Область | Телекоммуникации | Телекоммуникации | Телекоммуникации | Телекоммуникации |
| Семейство | Process / pipeline | Process / pipeline | Process / pipeline | Process / pipeline |
| Год появления≠ | 1990 | 1995 | 1971 | 1970 |
| Автор метода≠ | Phil Karn | Telatar, Foschini, and Gans | Weinstein and Ebert | Norman Abramson and Lawrence Roberts |
| Тип≠ | random access protocol | spatial multiplexing technique | multicarrier modulation scheme | random access protocol |
| Основополагающий источник≠ | Karn, P. (1990). MACA—a new channel access method for packet radio. In Proceedings of the ARRL/CRRL Amateur Radio 9th Computer Networking Conference, 134-140. link ↗ | 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 ↗ | Roberts, L. G. (1975). ALOHA packet system with and without slots and capture. ACM SIGCOMM Computer Communication Review, 5(2), 28-42. DOI ↗ |
| Другие названия≠ | medium access control, WiFi MAC | spatial multiplexing, antenna diversity | multicarrier modulation | random access, medium access |
| Связанные≠ | 3 | 5 | 5 | 3 |
| Сводка≠ | CSMA/CA is a random access protocol for wireless medium access control, designed to enable multiple devices to share a wireless channel while minimizing collisions. Introduced by Phil Karn in 1990, it is the foundation of WiFi (IEEE 802.11) and is now the de facto standard for unlicensed spectrum access. CSMA/CA combines carrier sensing (listen before transmit) with collision avoidance (RTS/CTS handshake) to improve channel efficiency and fairness, avoiding the efficiency loss of pure random access (Aloha). | 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. | Slotted ALOHA is a fundamental random access protocol enabling multiple devices to share a wireless channel without centralized coordination. Introduced by Abramson (1970) and refined by Roberts (1975), it divides time into fixed slots and allows devices to transmit at the beginning of a slot with a fixed probability. While simple and elegant, Slotted ALOHA achieves only 37% channel utilization under saturation (optimal traffic load), a fundamental limit discovered by Abramson. Despite this limitation, Slotted ALOHA remains a teaching tool and appears in modern systems like satellite and IoT networks. |
| ScholarGateНабор данных ↗ |
|
|
|
|