Sprint Developers

This article by Ben555 from HowardForums describes basic wireless technologies and protocols. All the common buzz words are here such as GSM, W-CDMA, UMTS, and EDGE.

VOICE

GSM and cdmaOne A are both 2G or second generation cellular system for
carring voice and data, both work on the same basics. If you want to know more
about this visit gsmworld.com in the history part.

TDMA or Time Division Multiple Access is a technology for delivering digital
wireless service using time-division multiplexing. TDMA works by dividing a
radio frequency into unique time slots and then allocating slots to different
users (2 each). In this way, a single frequency can support multiple,
simultaneous data channels. Mostly used in the Americas.

PDC is the same as TDMA but used as GSM cellular system.

W-CDMA and cdma2000 are both 3G or third generation of mobile communication.
the improvements between the 2G and 3G are better voice quality and a bigger
bandwith, IP traffic, greater capacity and improved spectrum and better roaming

UMTS or Universal Telecommuncation System is commonly used alongside the term
3G in Europe. This can be confusing however, as UMTS refers to a specific
implementation of W-CDMA within the 2.1GHz band which is the frequency that is
made available for 3G in Europe and other parts of the world. It is an
implementation of 3G.

The follow up of technologies are going to be:

• cdmaOne -> cdma2000 1x -> cdma2000 1x EV-DO or EV-DV
  
• TDMA to cdma2000 1x or to GSM (most will use GSM)
  
• GSM -> GPRS -> EDGE -> W-CDMA

So you are going to have 2 systems CDMA2000 and W-CDMA

PUSH TO TALK

Push to Talk is a one-way communication function in a mobile phone which lets one
user at a time talk to another user or a selected user group. Push to talk is
activated by pressing the push to talk key or equivalent on the phone. In a
user group, the turns to speak are requested by pressing the push to talk key
and granted on a first come, first served basis.

Push to Talk over cellular is a service that provides direct one-to-one and
one-to-many voice communication in the cellular network. Calls can be started
both to individuals and to talk groups with just the push of a key. Call
connection is almost instantaneous and the receiver does not have to answer the
call. A specifically PoC-enabled terminal is needed for the service.

DATA for GSM

GPRS or General Packed Radio Service: is a packet based technology for data
transfer over an IP-based network and used as an enhancement for GSM networks,
The speed of a GPRS capable device depends on how many timeslots (1 to 8,
shared by active users) within a TDMA frame are used. Up and downlink are
treated separately and various radio channel coding schemes allow bitrates from
9 to over 171.2 kbit/s (if device were to use all 8 channels without error
correction) per user

HSCSD or High Speed Curcuit Switched Data: is an enhancement of current GSM
networks allowing users to send and receive data with higher speeds. This is
achieved by increasing the speed of one channel as well as giving the option of
using several channels at the same time, which results in speeds close to 60
Kbps. This makes HSCSD particularly interesting to people who want to access
the Internet at higher speeds than current GSM phones.

EDGE or Enhanced Data rates for Global Evolution (EGPRS): EDGE is being
developed to be the basis for a 3G wireless standard which can be used by TDMA
and GSM operators. It works with a new modulation technique which allows for
better usage of existing frequencies. This means that EDGE can be deployed on
existing GSM networks. EDGE enables data transfer speeds of up to 384 kilobits
per second. This translates to 48 Kbps per timeslot enabling three times the
data speeds of GPRS.

W-CDMA or Wideband Code Division Multiple Access is a 3G technology used in
UMTS. Data transfer speeds go up to 2 Mbps, and due to the efficient use of the
radio spectrum, a wealth of different services can be accessed simultaneously
including circuit and packet services with varying bandwidths. W-CDMA data
transfer speeds will go up to 10.8 Mbps.

HSDPA or 3.5G, not much is know about it, but this will be the GPRS of a 3G
network, in run up to the 4G network, but this is future talk, not before
2010...

DATA for CDMA2000

cdma2000 is an IMT-2000 standard and included in the evolution part from
cdmaOne.

cdma2000 1x will double the voice capacity and allow up to packet-based data
transfer speeds of up to 307 Kbps.

cdma2000 1xEV, the next step, will allow for up to 2.4 Mbps data transfer rates
(1xEV-DO, data only) and 4.8 Mbps in phase 2 (1xEV-DV, data and voice).

WIRELESS PROTOCOLS

WAP or Wireless Application Protocol: a protocol to discribe how data is send
and transmitted to a mobile phone.

WML or Wireless Markup Language: a markup language based on XML. it a browser
context how text and images will be showed on a small screen device. XHTML is a
more advanced Markup Language.

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Reposted with permission. Thank you Ben555.