Cell Phones


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Information about Cell Phones

Cellular Overview



The basic concept of of the cellular phone employing "cell" technology was designed in 1947.

A service area consists of many base stations that divide the area into cells, hence the term "cellular phone."

As the user travels, the calls are being transferred from base station to base station, which effectively is "cell" to "cell."

Cell phones have come a long way since the early cell phones of the 80s. Not only do today's cell phones offer clearer signals, many of them will allow you to surf the web, send & receive email, and listen to MP3s. Some plans offer unlimited nights and/or weekends,

and in certain areas it is possible to subscribe to a plan that gives you unlimited minutes. Billing options have also been made easier. It is possible for every member of a family to be equipped with a cell phone under one plan. There are also business plans that offer similar options. The choices can be overwhelming at times.

Where to Begin

When purchasing a cell phone, there are actually 2 items you are purchasing, the cell phone and the plan. The typical cell phone plans are 1 or 2 year agreements that obligate the customer for that period time, and early cancellation would result in termination of the plan which normally incurs a large penalty. For this reason, it is important to make an informed decision.

The Carrier

It is best to determine which carrier to use and select a phone based on what the carrier offers.

The carriers often offer a wide range of phones to choose from. The keys things to consider when select a carrier is which one has the best coverage in your area, the features that you want, and in the back of your head, the one with the style of phones that you want (for example, getting a PDA cell phone may be of highest priority for you and the carrier may not support that, therefore the carrier cannot be considered as a viable option). And of course, you must also consider the price.

To find the coverage, first look at the regional map of your carrier and see how well the area is covered. If the coverage looks acceptable to you, you should not stop there. Browse newsgroups and talk to friends and family who use the same carrier. What do they say about the carrier? Do they get a good signal? Do they miss a lot of calls? Are they able to make a lot of calls? These are some of the questions you will want answers to.

You will also want to make sure that the features you want are being offered by the carrier. Some features that are available by some carriers, but not by others are Internet browsing, SIM cards, and text-messaging.

For our purposes, we will simplify this discussion and say that there 3 main technologies being utilized by carriers in the US: TDMA, CDMA, and GSM. Each has its own advantages and disadvantages.

TDMA stands for Time Division Multiple Access. On TDMA, users share the same frequency but only for "very short periods of time." These "very short periods of time" are assembled together quickly to emulate a constant voice stream that ordinarily sounds normal and acceptable to the human ear. Out of the three mentioned technologies, this one is the oldest. Because it is the oldest in the US, it also normally provides the best coverage and is the most widely accepted.

Shortly after TDMA, work begun on what was going to be a competing technology called CDMA which stands for Code Division Multiple Access. A key difference between TDMA and CDMA is that CDMA had everyone transmitting at the same time but each signal is distinguished by an encryption. Imagine you and your spouse being in a room full of other couples, and you had to come up with a method of talking to your spouse that would not interfere with the other couples' chatter. In TDMA technology, each couple would take turns talking. Only one couple would be speaking at a given time, while all the other couples in the room remain silent. In CDMA, all the couples would be speaking at once, but each couple would have a unique language, so no other couple could understand what the other couples are saying. Overall, CDMA provides better sound quality but its coverage is limited worldwide and may be limited in you area.

The third technology is GSM which stands for Global Systems for Mobile Communications. It is actually a flavor of TDMA. Its sound quality is comparable to CDMA. Its biggest strength is the fact that it is widely accepted worldwide, as the name implies. Another significant advantage of GSM is its use of SIM cards. However, the US has been somewhat slow in making the conversion to GSM and coverage in your area may be limited.

So, where does all this leave us? The audio qualities of all 3 are too marginal to impact a change on carrier. If you travel frequently and have good GSM reception in your area, then GSM is certainly for you. In fact, all things being equal, GSM would be the best choice. If you have to decide between CDMA and TDMA, then CDMA may be a better choice if the coverage is good in your area.

The Phone

At first, selecting a phone seems like a daunting task, but it's quite simple. Look for the phone with the right look and features that you want.

Obviously size and weight are serious considerations. Normally, people want smaller phones, but smaller phones mean smaller keypads which makes it harder to press the buttons. Internal vs. external antenna? Internal antennas tend to have a nicer look and are slightly smaller than their counterparts. External antennas provide better reception. While we are on the subject of reception, you will get a choice as to how much bandwidth your phone will cover. As of the time of this writing, the choices are normally: single band, dual band, or tri band. A tri band phone increases the likelihood of receiving a reception on your phone.

Some features to consider are ringtones (sometimes they are downloadable), connectivity with a computer, talk time, standby time, WAP, and text-messaging. Some of the newer phones allow the user to connect their cell phones to a PC via serial cable, infrared, or Bluetooth™. Talk time and standby time rely on battery strength and how efficiently the cell phone consumes power. WAP stands for Wireless Application Protocol. Effectively what it does is allow users who own a WAP-enabled phone to browse the Internet. This may or may not be important to you. Lastly, a consideration is text-messaging. Text-messaging is a fairly standard feature now. It can be used in situations like concerts where you would like to give a message to someone, but it would be impractical to call. And do not forget that if you select a GSM phone, you will get a SIM card which is a nice perk.

Time to Buy A Phone

So, now you have done your research and you know which plan and which phone to get. Is it over? Not quite. You need to decide where you want to buy your phone from. You can choose to buy one (possibly used) from eBay or an online vendor. You can purchase one from an electronics retailer such as Circuit City or Best Buy. Or you can go to your local carrier retail center to purchase one.

The best place to purchase a cell phone would be online. Often times, you have rebates available to you for purchasing a new often, and the online vendors can often offer an additional substantial in-house rebate. They can do this because they in general have lower overhead costs. You may also be able to avoid sales tax by buying online (especially when free shipping is offered). The next best place to purchase a phone would be from an electronics retailer who can also offer an additional in-house rebate, but they are normally not as impressive as the ones online vendors offer. Purchasing directly from the carrier is advised against because you generally would only be entitled to the standard promotions and rebates and not additional ones that an electronics or online vendor can throw into the deal. Now one might be wondering, "What is good the retail stores that the operate?" (such as the AT&T Wireless Store). Often times, you will need to go these stores if you want to make changes to your plan, invoke the warranty, etc. But for your first purchase, the best place to go is online.


What purchasing a cell phone requires is making a decision that satisfies your needs. The best systematic approach to deciding on a cell phone is to select a carrier that has adequate reception and acceptable calling plan. If you end up deciding on a cell phone first, you may compromise too much on the plan you select, and end up carrying a rarely used device. Once you have selected on a carrier, then select a phone that carrier has to offer. Make sure the phone has the features you want (I went over some of the basic ones). And once you have made your decision, choose wisely on where you want to purchase your phone; Choose an online site (no sales tax and often free shipping) or an electronics retailer for more rebates and better prices.