Cellular Data Primer
By Chris De Herrera, Copyright 2006
 Version 1.00  Revised 6/18/2006

After working with Windows Mobile and wireless for many years I still hear from users about their confusion about what cellular wireless data capabilities and limitations.  This article will help explain to the user what data options are available to them and the characteristics to consider when making a purchasing decision.

Cellular Technology Overview

Before we begin to focus on the wireless data you will need to know what types of cellular technology your cellular carrier offers.  In the United State, there are two competing standards for cellular data.  The first is called CDMA which evolved from the first cellular service offered.   The second is called GSM and it was the first digital service.

What does 2G and 3G Mean?

One of the first characteristics you may hear about wireless data is something like 2G or 3G and how that 3G is better.  Let me explain what this means.  The G referred to here is a generic term related to the generation of wireless that a carrier is offering.  So there currently are 3 generations of wireless commonly referred to as 1G, 2G and 3G.  Occasionally some vendors will refer to intermediate increases in performance as 2.5G.

This table explains what type of cellular data is applicable to the generation of wireless:

The carriers have chosen quick phrases like 1xRTT, EvDO, GPRS, EDGE and UMTS to make it easy for a user to refer to the type of data services they offer.   

Cellular Data Features by US Carrier

So now you have a better idea what types of data services the carriers can offer.  However each carrier has made their own decisions regarding what data services they offer.  Here is a table of the current data offerings by carrier:

Please note that Cingular UMTS operates at a different frequency than UMTS in other countries.  For example if you purchase the iMate JasJar which support UMTS from a 3^rd party vendor it will not work with Cingular’s UMTS.

How much will it Cost Me?

Cellular wireless data services are an additional cost for users.  Data access is currently not bundled with voice plans however this may change in the future.  You can expect to pay from $30 for T-Mobile to $60 for Verizon per month.  Make sure you contact your carrier so you are aware of the actual cost per month which may vary.

As part of your decision you should be aware that the United States is unique in the world because the cellular carriers here offer unlimited data plans.  In the rest of the world, users pay for every kilobyte of data so watch out when you are roaming outside the United States!  An exception is T-Mobile's 10 Euro plan for 1 GB per month.

Coverage, Coverage, Coverage

An additional consideration is the cellular data coverage for the protocol you want to use.  The coverage for data is different than the coverage for voice.  For example the ability of  Verizon and Sprint users to use EvDO is based on where the carriers have implemented it.  So you will want to contact your carrier and review whether they offer high speed data were you live, work and plan to visit.  I highly suggest that after you have made a purchasing decision that you test the coverage where you plan on using your device.  That way you know before you try and depend on it what coverage you can expect.

One other feature of coverage is that data connections are affected by more than just having a signal.  Services like GMS, EDGE and 1xRTT all use the same channels as voice calls to provide data services.  So if the tower in your area is inundated with voice calls then you won't get the full throughput of the connection.  Also, if you are in a fringe coverage area, you may be able to connect to data services however you may experience intermittent drop outs of data coverage and delays in downloading content.

Windows Mobile Device Features

One other major factor for you in choosing the data services that best meet your needs is to consider what data protocols your device uses.  For example most GSM phones available today support GPRS however most of them do not support EDGE or UMTS.  So you will probably have to purchase a new device to take advantage of the highest speed data capabilities your cellular carrier offers.  Windows Mobile 5.0 devices support EvDO for CDMA and UMTS for GSM customers.  Prior versions of Windows Mobile may not have the advanced data features you want.

Identifying Your Connection on Your Windows Mobile Device

When your Windows Mobile device (Pocket PC or Smartphone) is able to connect to a cellular data network, it will display a box in the inverse color of the home page next to the Antenna icon with an abbreviation for the connection type.  Once you are connected to the data network it will display the right and left arrows (the same arrow displayed when it is synchronizing).

Connection Abbreviation	Data Connection	Icon
G	GPRS
E	EDGE
1X	1xRTT
EV	EvDO
1X EV	1xRTT and EvDO Available
U	UMTS

Conclusion

Now you have a better idea about what data services cellular providers offer and how you can take advantage of them.  Just be careful to make sure that you test device where you want to use it before your return period has expired.  Wireless data is a great tool.  I use it daily and filed this article using EDGE.