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The Radio Frequency Block sends and receives signals to/from portable devices (via the air interface) and converts between digital data and antenna signal. Some of the main functions are D/A and A/D conversion, up/down conversion, carrier selection, linear power amplification, diversity transmit and receive, RF combining and RF filtering.
It contains the base stations, which are called Node B's and Radio Network Controllers (RNCs) [1] which make up the Universal Mobile Telecommunications System (UMTS) radio access network. [2] This communications network, commonly referred to as 3G (for 3rd Generation Wireless Mobile Communication Technology), can carry many traffic types from ...
WSDMA (Wideband Space Division Multiple Access) is a high bandwidth channel access method, developed for multi-transceiver systems such as active array antennas.WSDMA is a beamforming technique suitable for overlay on the latest air-interface protocols including WCDMA and OFDM.
GPRS Tunnelling Protocol is the defining IP-based protocol of the GPRS core network. Primarily it is the protocol which allows end users of a GSM or WCDMA network to move from place to place while continuing to connect to the Internet as if from one location at the Gateway GPRS support node (GGSN).
Most 2G cellular systems, with the notable exception of IS-95, are based on TDMA. GSM, D-AMPS, PDC, iDEN, and PHS are examples of TDMA cellular systems.. In the GSM system, the synchronization of the mobile phones is achieved by sending timing advance commands from the base station which instruct the mobile phone to transmit earlier and by how much.
A block diagram is a diagram of a system in which the principal parts or functions are represented by blocks connected by lines that show the relationships of the blocks. [1] They are heavily used in engineering in hardware design , electronic design , software design , and process flow diagrams .
[1] [2] [3] In 1999 ITU approved five radio interfaces for IMT-2000 as a part of the ITU-R M.1457 Recommendation. [4] The five standards are: [5] IMT-2000 CDMA Direct Spread. also known as W-CDMA, used in UMTS, the successor to GSM; IMT-2000 CDMA Multi-Carrier. also known as CDMA2000, the successor to 2G CDMA ; IMT-2000 CDMA TDD. also known as ...
Code-division multiple access (CDMA) is a channel access method used by various radio communication technologies. CDMA is an example of multiple access, where several transmitters can send information simultaneously over a single communication channel.