Cellular networks are, in general, networks that internet mobile recharge cover large areas, for most of the time in a country. Non-cellular radio networks are commonly used to solve the problem of communications on specific areas or around a home, either in rural or suburban housing dispersed or in crowded areas, but with relatively small such as fairs, exhibitions etc. These systems can be configured as cellular recharge api systems, in particular, WiMAX, so that they can provide the coverage of relatively large surface area, without, however, reaching coverings made of cellular networks. 

 

Both Wi-Fi and WiMAX are made in several variants. The emergence and development has become necessary because GSM mobile communication systems of (NMT, AMPS, TACS so called generation mobile communication systems) no longer able to cope with the demand for press here means of communication in the field and no stresses to recharge api which they were subject to the new services, in particular data transmission. To cope with new demands and taking into account progress in communication techniques and circuit technology to recharge api achieve GSM was used digital processing (digital) signals.
 

This provides several technical advantages with respect to signal processing techniques used generation mobile communication systems. In this way, within GSM, together with other communication systems, the generation of the second communication system. The GSM developed in three main stages, called Phased. In phase were founded functional GSM transmission services being offered internet mobile recharge voice and circuit switched data, with transmission speeds of up to. To enrich the content services offered by GSM, initially offered only voice communication services and data transmission services on user channel with speeds of the order of.

 

By introducing operational GSM became operational a range of facilities and services that recharge api will be taken and the UMTS: As GSM carries out the processing and transmission of signals in digital form, it can provide a range of transmission services data at different speeds, the channel internet mobile recharge assigned voice transmission. These transmissions can be achieved for users POTS, ISDN, and CSPDN, using access methods and protocols such as X or X appropriate. A communication network contains actual network and that recharge api network users. In the particular case, the communication network may be GSM (Figure).
 

Users connect to the network with specific equipment user, named recharge api for the GSM mobile equipment. Users can communicate with each other only through the network and not directly. In the case of figure, the user communicating with the user, both being connected to the GSM network. If the network supports the communication connection with each other, a user in a network may more information communicate with a user in another network. GSM is the case as shown in Figure., communicates with the user. This other network can be a GSM network, telephone network, data transmission network etc. In this situation it is necessary that the two networks to achieve reconciling the transmission mode and the recharge api signs used.