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Mobile technologies (lecture 2)

Written by: Jonathan Briggs

February 8, 2005 [7628 views]

It is easy to get mired in a sea of abbreviations and acronyms when dealing with mobile technology. What is really important is building up a mental picture of what each technology is used for and how each is suited to different types of application or environment.

Here is a good glossary of mobile terms www.gsmworld.com

What are the current options?

GSM/GPRS (in the UK and Europe)
Bluetooth
802.11b (WiFi)
3G/UMTS

How do you choose an appropriate technology?

Cost (infrastructure and running costs)
Distance between data source and terminals
Bandwidth
Security
Charging models
Moving terminals versus mobile terminals

Understand your terminal (mobile)

Radio transmitter/receiver
Phone module (GSM)
Data modules (GPRS/3G)
Bluetooth module (Personal Area Network)
SIM card
Operating system
PIM functionality(calendar, phone books, document display)
Data storage device
Camera
Power consumption issues – how do we make batteries last longer?
Spectrum compression issues – how can we squeeze greater bandwith through finite spectrum?
Standards issues (with other technologies in the US/Japan) – how do we build compatible but commercially competing networks?
Coverage – need to be able to downgrade to lower bandwidth system in rural and poor coverage areas.
a basic tutorial on cell phones

Characteristics of different systems

GSM/GPRS

Global System for Mobile communication
900 Mhz, 1800 Mhz and 1900 Mhz part of the spectrum allocated specifically to mobile communications
1 billion+ GSM customers worldwide
Packet switched digital mobile network and terminals
Operates in 170 countries
Time division transmission
Very efficient voice compression
Upgradeable to GPRS (2.5G) for data, EDGE through higher compression and UMTS (3G)
a tutorial on GSM

Network components

Connected cell towers (radio – specific regions of the microwave radio spectrum) – terminals and towers negotiate digital connection
Calls can be passed between cells (cells stretch!) as edge of footprint is reached
Cells have capacity limits and are affected by terrain and buildings
Bandwidth is expensive although the cost is falling
All calls are made via cells – never directly between handsets
Routing and switching systems
Interconnections with IP and Telephone Networks
Roaming agreements allow handsets to connect to other networks (SOS calling or internationally)
Cells ‘know’ which terminals they are currently talking to and through triangulation can pinpoint location

Bluetooth

Short-range wireless (10 metres) replacing cables
720 kbps
34 million Bluetooth aware devices shipped in 2002
Public part of the spectrum (2.4 GHz) - frequency hops to avoid interference
Ideal for connecting devices (keyboards, mice, headsets, speakers, phones , mp3, games consoles, in car devices etc)
Can be encrypted
Devices are “paired” before communication (eg headset to phone)
Low cost – Bluetooth adapter for PC/Mac costs around £30
Small, low energy requirement (could be built into clothing)
Backed by a range of IT suppliers (including Nokia, Apple, Sony, Ericsson, Microsoft, Intel)
read more about Bluetooth at www.bluetooth.com

WiFi 802.11b/g

In location wireless networking
11 Mbps (shared) – 54 Mbps (for Apple’s 802.11g version)
Wireless bridging can extend range
Public part of the spectrum (2.4 GHz) - multiple channels
Some security issues
Ideal for connection of mobile computers (and soon phones) in different locations
Low cost – base stations (£100), PC cards (£30)
Ideal for “road warriors” who want to work wherever they are
Backed by a range of IT suppliers (T-Mobile, Apple, Starbucks, BT, Intel)
WiFi compatible mobile phones are planned
Experimental roaming
Business model possible for access providers (Open Zone)
more about WiFi on www.wifinetnews
read about Apple's Airport Wifi technology

Other technologies

GPS

US (military) satellite positioning system
24 satellites in geostationary orbit
Receivers measure the time taken to receive signals from three or more satellites through accurate synchronization of sending/receiving and hence distance
Triangulation of three signals allows distance to be calculated accurately (around 1m)
Requires clear line of sight although intermediate positions can be estimated
Does not require any communication from the receiver
Russia and the EU are constructing their own improved systems at the moment
GPS is being built into the some mobiles
a tutorial on GPS

RFID

Radio Frequency Identification Tags
Not a mobile technology at all but a physical identification technology
Small passive low-cost antenna coils are imbedded in tags, labels or security fobs
Attached to cards (Oystercard), products (VirginMega), cars (Easypass) or pets (PetPassport)
Tags can be ready when passed through an antenna gate or touched to a reader
Tags can store serial number which can then be looked up in a database
Thousands of tags can be read per hour (even while the tag is moving)
a good starting point for exploring the pros and cons of RFID

Recent comments:

On February 9, 2005 at 8:05 AM, Harminder Duhra wrote:

I would argue that RFID is a low cost technology. I have been exploring this technology since the summer... Walmart are making a big push to have its suppliers all RFID enabled otherwise they jeopardise their contracts. I have read recently in C Weekly that a lot of the courier services are not going to increase their usage on RFID as costs are still high. (DHL, Fed Ex)

I have seen the tags in action at the Enterprise Wireless Technology Exhibition (13-14 October 2004, Olympia). I was quite impressed with them i have to say.

Do you think one day RFID will kill the need for barcode?

On February 9, 2005 at 8:06 AM, Harminder Duhra wrote:

Also are we any nearer reaching international standards for the use of RFID?

On February 9, 2005 at 6:25 PM, Andy Stone wrote:

Interesting article on BBC News website about consumer concern over RFID tags. Even if some of the concerns are ill-founded, negative consumer perceptions could have an impact on the use of RFID in B2C markets.

http://news.bbc.co.uk/1/hi/technology/4247275.stm

On February 12, 2005 at 6:06 PM, Nagz wrote:

I agree with you Jonathan and Harminder’s comment:- RFID is a low cost technology. But I DISAGREE courier services such as DHL, FED ex and high street stores such as M&S and TESCO etc are not taking up this technology, not because RFID costs are still high. The key to this argument is all about lessons learnt and past experiences. What’s happening is no company which has implemented RFID is willing to share its experience in this field, nor information on direct cost saving and implementation and roll out etc.... It’s like any business they do not want to give away their secrets especially while the raw technology is new. It's a big gamble for any company to try implement RFID.. Even with the use of RFID trial’s.......

On February 12, 2005 at 6:10 PM, Jonathan wrote:

I don't think RFID will kill barcodes completely because they are virtually free but the added benefits of RFID are very compelling and the tags and equipment are coming down in price.

There is no universal standard for RFID and as Nagz says there is reluctance to share knowledge. Oystercard clearly has had lots of teething problems but I think it is a success and the foundations for a very much improved ticketing and access system.

On February 13, 2005 at 4:59 PM, Harminder Duhra wrote:

Nagz, Jonathan thanks for your input... It is evident that no one is willing to share knowledge and this is why companies are not taking their use of RFID further at the present. With uncertainties project timescales fail to meet deadlines, costs rise further.

I guess until these uncertainties clear up we wont see as much use in small - medium scale businesses.

On February 14, 2005 at 9:43 AM, MightyMike wrote:

New wireless usb technology, pretty nifty:

http://deviceforge.com/articles/AT9015145687.html

On March 3, 2005 at 1:14 PM, justinjfloyd wrote:

test

On March 8, 2005 at 2:57 PM, J. Floyd wrote:

Can you recommend any websites that give advice on designing websites and the architecture behind them for mobile applications preferably concentrating on Internet Explorer for Windows SmartPhones - thanks

Jonathan replies: The Orange Developers site has some info on designing for the SPV.

On August 2, 2005 at 7:08 PM, Martin Felix wrote:

Greetings: Do you know of www.paperclick.com ? It's pretty awesome

www.paperclick.com

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This site is an educational resource, a research project and a publication channel written by Jonathan Briggs, Professor of eCommerce at Kingston University.
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