An important feature of GPRS terminals (cell phones) is that they belong to one of the 3 functional classes:
1. Class C: only possible data transfer. Such terminals already on the market in the form of a PCMCIA card (a special device installed in a special slot in the computer or in a jacket pocket for a computer, and provides mobile Internet access), or handheld computers, organizers. However, their choice is limited.
2. Class B: terminals enabling transmission and voice and data, but not both. In general, it is conventional mobile phones with built-in GPRS modem. Most terminals sold today are of this class.
3. Class A: terminals that provide both voice and data simultaneously. This means that it is possible, and talk, and to seek information on the Internet at the same time. Such terminals are not yet available on the market, but it is expected that they will be executed in the form of handheld computers.
Also, it is necessary to note one of the most important cell phone and network settings - the number of channels to receive data when using GPRS.
GPRS feature of the phone is not only the fact that they make available GPRS service, but also what their characteristics are now define the maximum speed of receiving / transmitting data. GPRS technology allows for the transmission of data channels which are not occupied at any given time, a voice connection. The more channels are free from voice, the higher the data transfer rate through the GPRS can be achieved. Currently, the maximum capacity of one channel of 13.4 kbit / s. But the number of channels supported by the existing terminals on the market is limited: three, four (40.2, 53.6 kbit / s) for data and one, two, to send (13.4, 26.8 kbit / s).
Class 6 - the ability to work with 3 channels for receiving and 2 channels for transmission, but no more than 4 channels total. Class 8 - is the ability to work with four channels for receiving and one channel for transmission, but no more than 5 total channels. Class 10 - is the ability to work with 4 channels for receiving and 2 channels for transmission, but not more than 5 in all channels.
At this point, Biline GSM network is able to provide five channels for reception and one for transmission. In the very near future, it will be provided the opportunity to network to work already with 2 channels for transmission.
GPRS in the MTS
GPRS-terminal class describes the number of time channels, which is supported by software. You can use GPRS-terminal of any class. From the beginning of MTS GPRS network commercial operation is maintained until 4-time channels to incoming and outgoing traffic.
GPRS into a megaphone
Terminal classes differ in the number of time slots used for data transmission. In MegaFon network the maximum possible number of time slots that can take advantage of the subscriber - 4 at the reception information (downlink) and 1 for sending (uplink). The maximum data transmission each time slot rate - 12 kbit / s information rate t.e.maksimalnaya -. 48 kbit / s. The network has priority voice traffic. And depending on the load of the base station number used to transmit data time slots can be reduced.