Introduction to the Course Justin Champion Room C208 - Tel:

Introduction to the course Contents  What are we looking at  History Digital to analogue  Mobile technology Breakdown of the course Assements

Introduction to the course What we are looking at  Mobile devices using cellular communications  Looking at how they work  Uses of this technology  We are not considering Mobile voice technology Wireless Technology  Wi-Fi  Bluetooth  These do not support any roaming

Introduction to the course Evolution of Personal Communication System’s Analogue DigitalMultimedia 1980’s 1990’s

Introduction to the course History  1876 Graham bell creates the phone  1878 First exchange in Connecticut, USA. Gradual spread  Analogue Publicly Switched Telephone Network  Used throughout the world  1979 (ISDN) Digital Communications started on the PSTN  1985 Mobile phones start in the UK  1993 ADSL introduced  2001 GPRS service started  2004 EDGE predicted to start  200? 3G service starting This is ongoing if ever to happen as discussed in lectures

Introduction to the course History of the phone  Created by Graham Bell in 1875  He created what we know as a microphone  In 1876 the patent for a telephone was submitted  1878 first telephone exchange was created In New Haven, Connecticut, USA

Introduction to the course Publicly Switched Telephone Network (PSTN)  Also know as Plain Old Telephone System (POTS)  This is the telephone network we all use every day Wired Controlled by British Telecom in the UK Parts of the network are Analogue  Increasingly using Digital Communications  Last mile is still analogue today!

Introduction to the course Communicating  To allow communication a circuit must be completed between two phone devices  This circuit will then allow the analogue signals to travel between them Voice in the early days

Introduction to the course Switching  The first automated exchange was created in 1889  Almon Strowger a undertaker created this exchange He was annoyed that a opposition undertaker who’s wife worked in the exchange was getting all the burial work

Introduction to the course - Analogue Analogue problems  Further the signal travels the weaker it gets  A clear signal will degrade Loss power Also gain interference Time / Distance Strength

Introduction to the course - Analogue Hello

Introduction to the course - Digital Digital Communications  Allows accurate sending of signals  The signal still degrades  It is possible though to still get a signal back even with loss v -5v

Introduction to the course - Digital Analogue to Digital Conversion (ADC)  Regular samples are taken from the signal Each given a value depending on the number of bits  Example shown uses 8 bits

Introduction to the course - Digital Analogue to Digital Conversion (ADC)  Regular samples are taken from the signal Each given a value depending on the number of bits  Example shown uses 8 bits storing values between 127 &

Introduction to the course Sampling Rate  Needs to be sufficient to gain all of the analogue signal If it is not a lot of the signal is lost as in the example shown in the previous example Nyquist’s law tells us the minimum sampling rate  Sampling Rate = Highest Frequency * 2  Telephones use 3.4 KHz sampling rate for voice calls 8 KHz for digital calls 1 KHz = 1000 cycles a second

Introduction to the course PSTN Modular  The PSTN is a modular design  New parts can be added to the network as required Mobile communications Satellite Communications  SS7 allows this as discussed in a future week

Introduction to the course Mobile Communications  Started with Mobile phones Which were voice only Limited battery life Limited roaming capability Limited quality Unsecured  Advent of Digital phones Allowed for better use of this phone technology Allowed the user to roam and receive calls anywhere Call were encrypted The use of digital communications also allowed for data calls

Introduction to the course Roaming capability  Brought forward technology Dual/Tri Band phones Satellite phones  Expensive about £1.20 a minute for a world phone call  This allowed the user to move from the office/home environment and still be connected.  Laptops As computers got smaller it was now possible to carry it with you As the computer is available the data was required for it

Introduction to the course Data Use  GSM phones allowed 9.6 Kbps data communications Enough for and simple file transfers  SMS messaging is the most popular data use  Voice calls are coming to the peak of the popularity Additional avenues of revenue are required Increased data is a obvious choice Charge the user for the packet received Charge for the services they are accessing i.e. Football results service

Introduction to the course Personal Communication Services (PCS)  We will soon have the ability for anyone to access digital information like the Internet. Unlike the Internet, there will be value added service from day one  Video on Demand  Paying your credit card bill  Ordering services Value added services will be the primary goal of the PCS  This will be needed to pay for the infrastructure and licenses paid for  Each user will be able to view the information as they want it Central control will not be put upon on the users Differing levels of hardware capability will effect the end presentation

Introduction to the course Weekly Breakdown  1 – This lecture  2 – 1G & 2G technology  3 – Device Technology  4 – General Packet Radio Service  5 – Enhanced Data GSM Environment  6 – Universal Mobile Telecommunication System (UMTS)  7 – CDMA 2000  8 – I-Mode and WAP  9 – 2G and 3G Handover methods  10 – PCS  11 – 4G, the future

Introduction to the course Assessment  Assignment 50% This will be one piece of written work of about 4000 words This work will need independent research by the student to discuss the topic of WCDMA  Examination 50% This will be a formal examination during the faculties exam period  Weighting The weighting of each part will be evenly split

Introduction to the course Summary  What is the Personal Communication System  What we will cover  What the assessment will be