Fornitore di apparecchiature di rete IT
An antenna gives the wireless system three fundamental properties: gain, direction, and polarization. Gainis a measure of increase in power. Directionis the shape of the transmission pattern. A good analogy for an antenna is the reflector in a flashlight. The reflector concentrates and intensifies the light beam in a particular direction similar to what a parabolic dish antenna would do to an RF source in a radio system.
Antenna gain is measured in decibels, which is a ratio between two values. The gain of a specific antenna is compared to the gain of an isotropic antenna. An isotropic antenna is a theoretical antenna with a uniform three-dimensional radiation pattern (similar to a light bulb with no reflector). The decibels over an isotropic radiator (DBI) value is used to compare the power level of a given antenna to the theoretical isotropic antenna. The U.S. regulatory agency (the Federal Communications Commission, or FCC) uses dBi in its calculations. An isotropic antenna is said to have a power rating of 0 db, meaning that it has zero gain/loss when compared to itself.
Unlike isotropic antennas, dipole antennas are real antennas. Dipole antennas have a different radiation pattern compared to isotropic antennas. The dipole radiation pattern is 360 degrees in the horizontal plane and 75 degrees in the vertical plane (assuming the dipole antenna is standing vertically) and resembles a doughnut in shape. Because the beam is “slightly” concentrated, dipole antennas have a gain over isotropic antennas of 2.14 dB in the horizontal plane. Dipole antennas are said to have a gain of 2.14 DBI (in comparison to an isotropic antenna).
Some antennas are rated in comparison to dipole antennas. This is denoted by the suffix dBd, short for decibels over a dipole antenna. Hence, dipole antennas have a gain of 0 dBd (= 2.14 DBI).
Note that the majority of documentation refers to dipole antennas as having a gain of 2.2 DBI. The actual figure is 2.14 DBI, but it is often rounded up.
Spec rapida
Tavolo 1 mostra le specifiche rapide.
| Modello | AIR-ANT2524DW-R |
| Tipologia di prodotto | Antenna |
| Enclosure Color | Bianco |
| Intended For | Wifi |
| Compatibility | 802.11N |
| Frequency Range | 2.4 GHz, 5 GHz |
| Gain | 2 DBI (for 2.4 GHz), 4 DBI (for 5 GHz) |
| Progettato per | Cisco Aironet 2802e Controller-based, 3802E, 1852E |
Piattaforme supportate
Tavolo 2 shows recommended supported platforms.
| Modello | Descrizione |
| Air-AP2802E-H-K9 | 802.11ac Onda 2 AP con CleanAir, 4×4:3, Antenna esterna, -Dominio normativo H |
| AIR-AP2802E-H-K9C | 802.11ac Onda 2 AP con CleanAir, 4×4:3, Antenna esterna, Dominio normativo H, Configurable |
| AIR-AP3802E-H-K9 | 802.11ac Onda 2 AP con CleanAir, 4×4:3, Mod, Antenna esterna, mgGig, Dominio normativo H |
| AIR-AP3802E-H-K9C | 802.11ac Onda 2 AP con CleanAir, 4×4:3, Mod, Antenna esterna, mgGig, Dominio normativo H, Configurable |
| AIR-AP1852E-C-K9 | Cisco AIR-AP1852E-C-K9, External antennas, 802.11a/b/n/ac Wave 2, 1.733Gbps thoughput, 4 X 4 MU-MIMO, Dual band |
| AIR-AP1852E-H-K9 | Cisco AIR-AP1852E-H-K9, External antennas, 802.11a/b/n/ac Wave 2, 1.733Gbps thoughput, 4 X 4 MU-MIMO, Dual band |
| AIR-AP1852E-C-K9C | 802.11ac Onda 2 Punto di accesso, 4×4:4, External-Ant, C Regulatory Domain, Configurable |
| AIR-AP1852E-H-K9C | 802.11ac Onda 2 Punto di accesso, 4×4:4, External-Ant, Dominio normativo H, Configurable |
Cos'è il Wi-Fi 6? (802.11ascia)
Wifi 6, noto anche come 802.11ax, sta cambiando il modo in cui ci connettiamo e consumiamo le informazioni. Il Wi-Fi 6 Lo standard si basa sui punti di forza dei precedenti standard Wi-Fi migliorando al contempo l'efficienza, flessibilità, e scalabilità.
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