5G, the second and one-half generation. Here, GSM evolved into General Packet Radio
Service (GPRS) and Enhanced Data Rates for Global Evolution (EDGE) and still continues its
evolution. Similarly, IS-95 evolved into CDMA2000 and it also continues to evolve.
During this time, various studies were undertaken in order to compare time division multiple
access (TDMA) against code division multiple access (CDMA) for the next-generation cellular system.
For reasons that will become apparent in latter sections, CDMAprevailed and we now have third
generation (3G) systems based on wideband CDMA(WCDMA). WCDMAcontinued to increase user
capacity and user data rates, thus further opening doors for wireless applications in both the circuit
switch (CS) and packet switch (PS) domains.
As we progress and gain global adaptation of WCDMA/CDMA2000 systems, we continue to
identify the fourth generation (4G) system which would not only continue on the road to increase data
rates and user capacity, but also support a variety of mixed services. These accommodations will also
be taken care of by improvements on the network side.
However, with history repeating itself, we see evolutions in the form of releases in the 3G systems.
These releases particularly address the Internet Protocol (IP) services, along with increased user data rates
to support such applications.
Pages:
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29