Wifi
From WugWiki
| Term | Description |
|---|---|
| Node | This is a wireless point. Your house is generally a node, this is the spot where the wireless equipment has been setup. |
| Pigtail | It is a small cable that connects the Antenna and the AP or the Antenna and the coaxial cable connected to the antenna. |
| AP | Access point. This is the actual device that connects your network to the wireless network. |
| LMR400 | This is the coaxial cable that is used to connect the AP to the Antenna. The LMR400 is actually a type of cable you get
other cable aswell, LMR195 is another type of cable the difference being that the LMR400 has a loss of 0.2dB/m where as LMR195 has a loss 0.6dB/m, so from this you can see that LMR400 is better than LMR195 and that having less cable is advised. |
| dB | a logarithmic unit of sound intensity; 10 times the logarithm of the ratio of the sound intensity to some reference intensity (I googled for that) Basically it is the Signal strength, high dB is GOOD! From the definition you can see that it is a logarithmic unit which means that the difference from 1 to 2 is HUGE so you want as little loss from your equipment as possible. |
| dBm | A power measurement unit. Decibels relative to 1 mW. dBm is calculated by using the ratio of some power (expressed in mW) to 1 mW.%%% eg. A dBm value of 0 is equal to 1mW, while a dBm value of 16 would be equal to 40mW.%%%%%%For every 3 increase in dBm, the power is doubled. See the [dBmChart] for a list. |
| dBi | A gain measurement unit. Decibels relative to an isotrope |
| dBd | A gain measurement unit. Decibels over dipole, a relative gain measurement with respect to a half wave dipole (0 dBd = 2.14 dBi) using a standard dipole antenna as a reference |
| Attenuation | A decrease in signal magnitude between two points. These points may be along a radio path, transmission line or other device. |
| Isotropic Radiator | An isotropic radiator is a transducer that produces useful electromagnetic field output in all directions with equal intensity, and at 100-percent efficiency, in three-dimensional space. If used for signal reception, the device is equally sensitive in all directions. In wireless communications and broadcasting, the isotropic radiator (also called an isotropic antenna) is a theoretical ideal. It is sometimes referred to as a point source. |
| Gain | A logarithmic measure of how well an antenna radiates or receives when compared to a reference antenna (a perfect point source dBi or a half wave dipole dBd), this can be highly directive with the intensity varying greatly over small angles. |
| Signal Strength | This is the SNR value of your link, it is measured in dB's and the higher the number the better. |
| SNR | Signal to Noise Ratio, basically your signal strength is compared to the noise that you are recieving, the objective is to get a high SNR. |
| LOS | Line of sight. Are the source and destination in clear view of each other with no obstructions. Since radio waves propagate differently to visible spectrum wavelengths, radio line of sight can still achieved even if no clear path is visible. |
| Brick | This is not a well known term but it is very often used. For a nice description please see [Brick] |
| WDS | Wireless Distribution System, Allows you to connect two access points to each other and still act as an access point accepting client connections. Both AP's must be on the same channel and have the same wep/wpa keys setup but can have different ssid's. |
