GSM and GPRS Technology
As GSM (Global System for Mobile communications) continues to assert
itself as the world's leading cellular communications technology, the
addition of GPRS (General Packet Radio System) has enabled "always
on" data connectivity to IP-based systems and opened up a host
of new applications. Plextek has a strong track record in GSM handset
design and GPRS data product design including the development of the
latest advanced GSM and GPRS multi-media cellular products. The photograph
to the right shows a GSM/GPRS multi-media handset design, undertaken
by Plextek for Alphacell and now in full production. It was developed
from a Plextek GSM reference design and features tri-band operation,
still and video capture and transmission, video and internet gaming,
web-browsing, Email access, conference calling and Bluetooth
connectivity.
Plextek's success in GSM/GPRS product design is underpinned by the
availability of reference designs that allow a rapid transition to market.
The availability of such reference designs gives a solid starting point
that facilitates rapid product development. Commencing the design process
with a fully functional development platform is the only sure way of
turning product ideas and requirements into a high volume cellular communications
product in a commercially viable time-frame.
Partnership agreement with Wavecom
As part of a partnership agreement with Wavecom,
Plextek is currently undertaking the design of a GPRS enabled telematics
unit. It is aimed at applications such as fleet management and road
use charging, and includes GPS location capability. Multiple interface
options are available including CANBus and Bluetooth. This reference
design is a generic platform that can be customised to meet the specific
needs of clients with high volume requirements.
Turnkey
Development Services
Plextek is able to carry out complete product and system development
for cellular and non-cellular applications of GSM/GPRS through its comprehensive
turn-key services covering:
- Product definition
- Industrial design, mechanical design and tooling
- Hardware and Software interface customisation
- Application development
- Supply of product samples
- Support through trials and regulatory approvals
- Provision of factory test equipment
If you would like to discuss your GSM/GPRS product requirements in
more detail please contact us.
Factory Support
We
recognise that GSM/GPRS product alignment and test in the factory are
highly complex, requiring very close integration between product and
test suite. At the same time we recognise the importance of fast-time-to-market.To
de-risk this activity we have developed a very comprehensive test system
that fully exercises the core technology and the MMI.
The test system uses National Instruments "Test Stand" test
executive in conjunction with test libraries written by Plextek. The
use of a commercially available test executive helps ensure on-going
access to support and training for the factory.
This design is offered under licence to manufacturers.
Past GSM/GPRS Development by Plextek:
Product Development
Plextek has an established history in GSM and GPRS and their combination
with other communications technologies. Much of our work is underpinned
by reference designs, developed internally to de-risk and speed-up the
route to final product.
Our GSM/GPRS technology is backed by the highly established protocol
stack and MMI design tools from TTPCom Ltd, which have been adopted
by over 20 major terminal suppliers. Our GSM hardware platform employs
the Hitachi Bright™ family of RF IC products and Analog Devices
SoftPhone™ family of baseband processors.
Alongside terminal product development we engage in a wide range of
other GSM-related work addressing the infrastructure and bespoke applications:
- DSP and RF design for
smart antenna systems, for increasing cellular network capacity.
- Firmware for encoding/decoding, encryption, authentication, integrated
configuration management. Modem drivers for MS Windows, etc.
- Software development for MMI and user-applications.
- Linear RF power amplifiers for Terminals and Base Stations, using
digital pre-distortion and analogue feedforward techniques.
Application Examples
GSM provides voice services (through a range of transcoders for differing
speech qualities), Short Message Service (SMS), circuit-switched data
(CSD) and High Speed Circuit Switched Data (HSCSD). GPRS creates a packet-switched
overlay for the GSM network providing IP connectivity to the Internet
and Intranets. The result is a cellular technology capable of supporting
a very broad range of services:
- Mobile multi-media and gaming
- Video Multi-media Message Service (MMS)
- Mobile Internet and Intranet access
- Location
- E-cash and "credit card" payment
- Vending
- Telemetry and remote monitoring
- Intelligent traffic management
Alongside its public telecommunication application, GSM/GPRS also continues
to capture some of what has traditionally been the Private Mobile Radio
(PMR) market. Examples being the GSM-R European Radio Network (under
teh Shengen Group), and certain emergency services (such as the Ambulance
in the UK).
Standards overview
GSM/GPRS standards encompass a wide range of functionality and performance.
Three Terminal Classes:
Two Multi-slot types:
The range of data rates is substantial. Those of primary interest today
being: GPRS up to 53.6kbps, GSM (circuit switched) 14.4kbps, GSM High
Speed Circuit Switched Data (HSCSD) 53.6kbps (Coding Scheme 2) and 85.6kbps
(Coding Scheme 4).
At Plextek we are currently focussing on Class B and Multi-slot up
to Class 12 - in line with the medium term capabilities of deployed
Networks and viable terminal economics.
EDGE (Enhanced Data rate for GSM Evolution) offers further throughput
improvement for GSM by adopting 8-PSK modulation in place of GMSK, thereby
taking peak data rates to 384kbps. A primary impact on Base-station
and Terminal implementations is the need for Linear RF amplification
- an area in which Plextek has considerable experience.
If you would like to discuss your GSM/GPRS product requirements in
more detail please contact us.
