Different technologies arrived that cater the needs of
business establishments and private users. High speed Internet access was a
need for businesses. It was a need for fast transactions and efficient way of
communicating with other entities. As years passed, wireless technologies were
created like General Packet Radio Services (GPRS), Enhanced Data for Global
Environment (EDGE) and Universal Mobile Telecommunication Services.
GPRS met the need of providing internet access using
radio links at a speed of 170 Kbps. GPRS can exist with current mobile station
with enhancement through software upgrades. It is a packet-based technology,
unlike circuit-switched technology, that is well suited for frequent
transmission of small amounts of data.
GPRS is ideally suited for applications such as
- Extended communications sessions
- E−mail communications
- Chat
- Database queries
- Dispatch
- Stock updates
EDGE came and took one step close to UMTS or the 3rd
generation technology. EDGE introduced a new modulation scheme for high speed
data rate which is the 8-Phase Shift Keying (PSK). 8−PSK enables each
pulse to carry 3 bits of information versus the GMSK 1−bit−per−pulse rate.
Therefore, EDGE has the potential to increase the data rate of existing GSM
systems by a factor of three. The channel separations
are 45 MHz, and the carrier spacing is a 200 kHz channel capacity, the same as
GSM and GPRS. The number of TDMA slots on each carrier is the same (eight) as
the GSM and GPRS architecture.
With true 3G up for
grabs, UMTS was one of which open the world of 3rd Generation
wireless technologies. UMTS a third-generation (3G) broadband, packet-based
transmission of text, digitized voice, video, and multimedia at data rates up
to 2 megabits per second (Mbps). UMTS
offers a consistent set of services to mobile computer and phone users, no
matter where they are located in the world. UMTS is based on the Global System
for Mobile (GSM) communication
standard. It is also endorsed by major standards bodies and manufacturers as
the planned standard for mobile users around the world. Once UMTS is fully
available, computer and phone users can be constantly attached to the Internet
wherever they travel and, as they roam, will have the same set of capabilities.
UMTS is incompatible with GSM. Some
phones are dual GSM/UMTS phones, but unless that exciting new
mobile phone or handset that you can't wait to get your hands on has that kind
of duality built in, you will only be able to utilize one mode, the one that
came with the device. As UMTS gains
in credibility and functionality, experts believe it will overtake GSM as the
industry standard. UMTS is
already able to operate at a higher frequency than GSM.
WCDMA is an ITU
standard derived from CDMA and is officially known as IMT−2000 direct spread. WCDMA
can support mobile/portable voice, images, data, and video communications at up
to 2Mbps (local area access) or 384 Kbps (wide area access). The input signals
are digitized and transmitted in coded, spread−spectrum mode over a broad range
of frequencies. A 5 MHz wide carrier is used compared with a 200 kHz wide
carrier for narrowband CDMA.
WCDMA offers very high
capacity with 50 to 80 voice channels per 5 MHz carrier (compared with 8 channels
per carrier with 200 kHz for GSM). To achieve the very high data rates, WCDMA
requires a wide frequency band of between 5 MHz and 10 MHz (compared with a 200
kHz carrier for regular (GSM).
This
figure shows a simplified diagram of a WCDMA system. This diagram shows that
the WCDMA system includes various types of mobile communication devices (called
user equipment - UE) that communicate through base stations (node B) and a
mobile switching center (MSC) or data routing networks to connect to other
mobile telephones, public telephones, or to the Internet via a core network
(CN). This diagram shows that the WCDMA system is compatible with both the 5
MHz wide WCDMA radio channel and the narrow 200 kHz GSM channels. This example
also shows that the core network is essentially divided between voice systems
(circuit switching) and packet data (packet switching).
With such technologies, the drive for
carriers to improve their services through improvements and innovation led to
convenience. These technologies are created most importantly for business use. Higher
speed data rates mean faster transaction that led to oppurtunities.

