The technology of wireless data transmission



For the transmission of data within wireless networks use radio waves, which are transmitted by the source router (router), transforming the incoming Internet wire signal format of the radio waves with a certain frequency and characteristics. Thus, the signal transmission distance, as in other radio channels is exposed to all sorts of interference.

There are several standards for wireless communication via wifi, which differ in range and frequency. Most often, the device may be used 802.11 g standard, which is supported by most network cards. The router with the standard gain (antenna with frequency 2 DB) allows the transmission of a signal to 50 metres indoors and 150 metres outdoors. The presence of walls seriously affects the transmission range of the signal, significantly limiting it.
Other important parameters of the signal is not only the type of Protocol the transmitter power amplifier and antenna, but the physical obstacles and created interference with other devices.


Obstacles to the signal



Seriously reduce the transmission distance of radio waves metal structure and brick walls, taking about 25% of the total signal. The amount of data lost may be determined and used standard. So, the access point operating in 802.11 a uses radio frequencies higher than 802.11 g or b, so it will be more sensitive to such obstacles. Microwave ovens also absorb the signal due to interference coming from them. The maximum range will have the access point working with 802.11 n, which allows to achieve communication range of up to 70 m of the house, and in open areas to obtain a large coverage of up to 250 m with close to ideal conditions for transmission.

Another obstacle is often the leaves of the trees containing water, which absorbs the waves transmitted by the router at a certain frequency. The range affected by the torrential rain that weaken the transmitted signal, or dense fog.
The range of a broadcast signal router can be calculated by using a special calculator, which specifies the basic parameters of the equipment used.


The increase in range of the network limited to one of the above reasons, is achieved by combining multiple routers in a circuit. Also, the device may be replaced with antenna that can boost signal by a few tens of meters.