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Cellular network standards and generation timeline. Lists and technical information: Mobile technologies. 2G networks (the first digital networks, 1G and 0G were analog): GSM. Circuit Switched Data (CSD) GPRS; EDGE(IMT-SC) Evolved EDGE; Digital AMPS. Cellular Digital Packet Data (CDPD) cdmaOne (IS-95) Circuit Switched Data (CSD) Personal Handy ...
Advanced Mobile Phone System (AMPS) was an analog mobile phone system standard originally developed by Bell Labs and later modified in a cooperative effort between Bell Labs and Motorola. It was officially introduced in the Americas on October 13, 1983, [ 1 ] [ 2 ] [ 3 ] and was deployed in many other countries too, including Israel in 1986 ...
Both the transmitter and the receiver support both analog FM and digital time-division multiple access (TDMA) schemes. Digital transmission is preferred, so when a cellular system has digital capability, the mobile unit is assigned a digital channel first. If no digital channels are available, the cellular system will assign an analog channel.
The North American Standards IS-54 and IS-136 were also second-generation (2G) mobile phone systems, known as (Digital AMPS) and used TDMA with three time slots in each 30 kHz channel, supporting 3 digitally compressed calls in the same spectrum as a single analog call in the previous AMPS standard. This was later changed to 6 half rate time ...
Although 1G also used digital signaling to connect the radio towers (which listen to the handsets) to the rest of the telephone system, the voice itself during a call is encoded to digital signals in 2G whereas 1G uses analog FM modulation for the voice transmission, much like a 2-way land mobile radio. Most 1G networks had been discontinued by ...
In the U.S., the analog AMPS standard that used the cellular band (800 MHz) was replaced by a number of digital systems. Initially, systems based upon the AMPS mobile phone model were popular, including IS-95 (often known as " CDMA ", the air interface technology it uses) and IS-136 (often known as D-AMPS, Digital AMPS, or " TDMA ", the air ...
D-AMPS: Digital Advanced Mobile Phone System based on TDMA; cdmaOne: Code Division Multiple Access defined by IS-95; PDC: Personal Digital Cellular; TDMA: Time Division Multiple Access; 2.5G: A set of transition technologies between 2G and 3G wireless technologies. In addition to voice, it involves digital communication technologies that ...
cdmaOne network structure. The IS-95 standards describe an air interface, [1] a set of protocols used between mobile units and the network. IS-95 is widely described as a three-layer stack, where L1 corresponds to the physical layer, L2 refers to the Media Access Control (MAC) and Link-Access Control (LAC) sublayers, and L3 to the call-processing state machine.