Federal Wireless-FWTS FAQ

Cellular telephone service is a wireless communications technology that provides high-quality mobile and portable communications. Using a cellular telephone installed in a vehicle or a hand-held portable unit, a user can place local and long distance calls to anywhere in the United States and Canada.

The concept behind cellular communications is a two-way radio link formed by reusing individual radio frequencies over and over again throughout a geographic area. Instead of using common, shared frequencies such as police, many commercial, and Citizen Band radios use to join a "party line " conversation, cellular customers are given "private line" service by being assigned unique frequencies throughout the duration of their call.

The Federal Communications Commission (FCC) allocated 832 channels to each cellular market. Additionally, the FCC awarded two licenses in each market. Therefore, each cellular company has 416 channels available to serve its customers. Each channel consists of two radio frequencies - one to talk, one to listen. This permits a full two-way conversation.

Cells Are The Key

Cellular telephone service derives its name from the way in which a city, county, or other geographic area is "carved-up" into smaller areas called cells. These cells range in size from one to twenty miles in diameter, depending upon terrain, and capacity needs. Each cell has its own low power transmitters, receivers, antennas, and common control computer equipment to provide and control the cellular service in its area. These cell sites are individually licensed by the FCC and are connected to a Mobile Telephone Switching Office, MTSO. The MTSO is interconnected to the telephone systems of the local telephone and long distance carriers. When a caller moves from cell to cell, the MTSO automatically transfers, hands off the conversation to a new channel in the cell.

Hand-offs ensure quality

This network of geographically dispersed cell sites gives cellular the power and flexibility to meet the needs of mobile users for the foreseeable future. Unlike conventional mobile telephone systems, cellular service allows the caller to drive from one end of the coverage area to another while maintaining high quality reception. The cellular phone puts out a signal that is detected by the cell site closest to the customer. The cell site communicates the presence of the customer to the MTSO that constantly monitors the phone's signal strength and selects the appropriate cell site to handle the call in progress. As the phone moves out of the range of the selected cell site, the MTSO sees the change in signal strength and finds another cell that can "see" the phone with a higher signal strength. The MTSO then transfers or "hands-off" the call from one cell site to another, adjacent cell site. The cellular system has the capacity to accommodate everyone who wants a mobile phone for business or personal use. As demand for service increases, more cells can be added to increase calling capacity.

What is the difference between cellular telephone service and conventional mobile service?

Cellular telephone service has the capacity to serve over 150,000 customers. Transmission quality is equivalent to a home or business phone and the service is just as easy to use. It also allows for immediate availability of a channel. No operator assistance is required. Conventional mobile service has limited quality. It is subject to lack of channel availability, static and radio interference, and requires operator assistance to process calls.

What is digital cellular?

The majority of today's cellular systems and phones use analog modulation techniques to carry information across the radio air waves. Cellular uses Frequency Modulation, FM, the same technique used in commercial FM broadcast stations to carry high fidelity music. To meet the continuing demand for cellular service, to offer customers more advanced voice, messaging, and data services, and to improve the efficient use of its assigned radio frequencies, cellular carriers are beginning to add digital cellular capabilities to their networks.

Digital Cellular: Digital Modulation

Digital modulation is a method of encoding and transmitting information (voice or data) by converting it into a string of digital bits, the 0's and 1's, of computer binary language. At the receiving end these bits are used to transform the information back to its original form - a spoken word. Digital transmission offers several advantages over traditional analog transmissions, such as, increased number of communication channels and higher immunity to static and signal fading. Additionally, digital cellular opens the door for exciting new services such as, integrated paging, messaging, data transmission, caller alert, etc. There are two major digital techniques being implemented in the cellular industry - TDMA and CDMA.

Digital Cellular: TDMA - Time Division Multiple Access

The first generation of TDMA implementations will offer a three-to-one gain in system capacity for cellular systems. This technique involves dividing an existing analog channel into three separate, time-based channels. Thus, one channel has three "time-slots" assigned to it and three separate conversations can take place.

Digital Cellular: CDMA - Code Division Multiple Access

CDMA is a next-generation digital technique that is a spread-spectrum approach to digital transmission. With CDMA, each conversation is digitized and then tagged with a code. Then the mobile phone is instructed to decipher only a particular code to pluck the right conversation off the air. In some ways, the process can be compared to an English-speaking person picking out the only other person who is speaking English in a room of foreign-speaking people. CDMA offers a ten-to-one increase in system capacity, significant increases in the privacy of conversations, and improved quality in areas of weak signals.

CDMA has been used in military applications for many years because it is highly secure and very tolerant of interference. In a cellular system, CDMA has a very desirable characteristic in that a phone will look at any cell site it can see and pick the best signal without intervention by the MTSO. This permits very fast "soft" hand-offs and improves the quality of calls in areas that were challenges in an analog environment. Vocoders also make the difference.

Understanding the quality of a carrier's digital offering is not as simple as which digital technique they offer. Perhaps the biggest factor in voice quality is the carrier's selection of the vocoder they deployed. The vocoder, or voice coder, is used to convert voice to a digital signal before it is modulated by TDMA, CDMA, or other digital modulation techniques.

With either TDMA or CDMA more conversations are being extracted from the existing radio channels. This means that less radio spectrum is being allocated to each conversation. The job of the vocoder is to represent the same amount information in a smaller space. Currently, the industry is standardizing on two vocoder techniques, 8kbps and 13.7kbps, named for the rate at which the conversation is sampled.

What is the history of cellular?

The mobile communications industry started in 1921 when two-way radios were installed in the cars of the Detroit Police Department. This equipment was bulky and awkward to use, but it allowed the department's scout cars to keep in touch with headquarters.

Soon private individuals realized that they too could benefit from mobile communications. The first commercial radio telephone service was introduced to the general public in St. Louis in 1946. No direct dialing capabilities were available. Therefore calls to and from mobile subscribers were routed through special operators.

There were long waiting lists to become a subscriber and once service was obtained, users often experienced long delays because only a small number of channels (radio frequencies) were available. Mobile units used a single channel, push-to-talk system that allowed only one person to speak at a time.

Although the creative thinkers at Bell Laboratories proposed the advanced computer technology necessary to make cellular communications a reality in 1946, AT&T did not introduce Improved Mobile Telephone Service (IMTS) until 1964. This service enabled subscribers to dial their calls without first reaching an operator. Channel (radio frequency) selection was automatic and wait time was considerably reduced. Although an improvement, IMTS was still limited to 44 radio frequencies and only a few people could use the system at any one time.

Lack of system capacity remained a problem, and in 1971, AT&T filed a proposal for the development of a commercial radiotelephone utilizing the 800 MHz frequency band, later to be named the cellular system. Chicago was chosen as the first city to test the cellular system. The first cellular radio system was named AMPS, Advanced Mobile Phone Service, began operations in 1978 and worked perfectly, as did another system built in the Washington, DC/Baltimore area in 1981. When the Federal Communications Commission (FCC) authorized cellular service in 1982, a new wireless industry was born.

Service Overview

Is it difficult to operate a cellular phone?

No. A cellular phone is as easy to use as a home phone. Enter the desired number, press the "SEND" button, and press the "END" button when your conversation has ended. With these two exceptions, everything else operates the same.

Do I have to go through an operator to place or receive phone calls?

No. Cellular service does not require users to go through an operator to complete calls. You can place and receive calls as you do from a home or office phone.

What is a service area?

The cellular service area is the boundary in which a cellular telephone may be operated. As long as you are within the cellular service area, you may place or receive calls, even long distance calls within the United States and Canada. The No Service lamp will illuminate when you are out of the service area.

Can I use my cellular phone while driving?

In the interest of road safety, it is advisable to pull off the road before placing a call. You may choose to have a speakerphone installed which enables "hands-free" conversation.

What happens if I'm driving along the highway and I travel from one area code to another?

Traveling from one area code to another will have no effect on your cellular conversation as long as you are within the cellular system coverage area.

Can I use cellular service on a boat?

Yes. Any cellular phone can be used on boats, provided you are in a cellular service area. Like any sophisticated electronic equipment, the cellular phone should be located in a secure dry place. Best performance can be obtained by using a marine antenna.

How will I know when I am out of the cell's range?

You will not notice if you are moving into a new cell in the system, because your call will automatically be switched to the new cell site without interrupting your conversation. If you leave the limits of a system, your signal will weaken as your leave the range of transmission.

How private are my conversations using a cellular telephone?

Your cellular telephone conversations are as private as any communication using radio waves for transmission. Sophisticated electronic equipment is available which will allow monitoring of cellular conversations. The large number of channels and cellular switching make continued monitoring difficult. The cellular industry is working with manufacturers of both network and telephone equipment to develop increased privacy techniques. The use of digital cellular services, where available, will significantly increase the privacy of cellular calls.

Will cellular telephones interfere with other radio reception?

No. Cellular telephones operate on a different set of uniquely assigned frequencies that should not cause interference with any other radio devices.

My job requires that I travel. Can I still use my phone outside of my "home" area?

Of course you can use your phone in any cellular city in North America. FWTS cellular carriers share "roaming" agreements with most systems in the U.S., Canada, and other parts of North America. These agreements enable FWTS users to place and receive calls on their cellular phones when traveling outside their home areas to cities served by different cellular providers.

Is it possible to receive calls while roaming?

Yes. To receive calls as a roamer there are two options. Regular roaming procedures require your callers to first dial a special 10-digit access number for the city you are visiting. Each city has its own access number. Callers then dial the area code and mobile number after hearing a dial tone or beep. Cellular roamers should leave specific itineraries and detailed roaming instructions with potential callers. If your cellular service has a feature referred to as "Follow Me Roaming" all calls will be automatically forwarded to you in any of the over 450 cities where it is available. Your callers don't even have to know you are out of town. So if you travel from city to city, your cellular service goes right along with you.

What kinds of phones are there?

The FWTS contract presently provides two varieties of cellular phones: car phones, and hand-held portable units. The portable (hand-held) cellular telephone is a completely self-contained unit with its own rechargeable battery. A portable cellular phone, although lower in power than a car phone, is growing in popularity because it can be carried in a briefcase or purse, allowing users to place and receive calls at all times when traveling within a cellular coverage area. The FWTS contract currently provides the following telephones as options for the FWTS users:

Motorola TeleTAC 250 - Hand-held portable

Motorola MicroTAC Lite II - Hand-held portable

Motorola 2900 - Installed car phone

Can you prevent unauthorized calls?

Many cellular telephones come equipped with an electronic lock which is activated by pushing the "lock" button. To unlock, you use a three-digit security code. After you push the "lock" button, no unauthorized calls can be made. They can be unlocked by using your personal security code. Refer to the telephone owner's manual for lock code. Refer to the telephone owner's manual for lock code and operation instructions. It is recommended that the code be written down and kept in a safe place. If you forget your security code, contact the company where your phone was purchased. The phone can also be wired to your vehicle's ignition so that when the vehicle is turned off, the phone cannot be used.

Can I connect my computer to my cellular telephone to send data?

Data can be sent over the cellular network through a special data connector cable from the modem to the cellular telephone. Although conventional modem will work over the cellular network, they often experience difficulties. The FWTS contract provides two types of cellular data modems that can be purchased as optional equipment. These modems are designed to work with the cellular network and have the same level of performance as their conventional counterparts. The FWTS contract currently provides the following modems as options fir the FWTS users:

Motorola CELLect 14.4 Kbps modem - PCMCIA card modem

Teleporte 14.4 Kbps modem - Serial interface modem

What are peak and off-peak hours?

Peak and off-peak hours represent different rate structures for different times of the day. Peak Hours for the FWTS contract are from 7:00 AM. to 9:00 PM Monday though Friday. Off-peak hours are from 9:00 PM to 7:00 AM Monday though Friday, and 24 hours on Saturday and Sunday.

How are calls timed for billing purposes?

Usage charges for calls originated by a cellular telephone begin when the send button is pressed and terminate when the end button is pressed. Usage charges for calls received by a cellular telephone begin when the phone starts to ring and terminate after the cellular telephone disconnects. FWTS user will not be charge for incomplete calls, busy signals, no-answer calls, calls to the Federal Wireless Service Center or specified emergency calls (refer to 9-1-1 "Emergency Services" section).

Are there any call restrictions?

Basic service provides for completion of all calls. Calling restriction services are offered so that usage is restricted at the FWTS user's option, through selection of any combination of the following services.

a. Operator assisted denial No 0+ access allowed.

b. Toll denial No 1+ access allowed.

c. Local service area only. Calling within the local service area only.

d. Local area codes. No 1+ calls may be completed outside the local area code.

e. Incoming only. No outgoing calls will be completed.

f. Outgoing only. No incoming calls will be completed

How do I make long distance calls on my cellular phone?

The GSA provides government users with long distance service through the FTS2000 contracts wherever possible. Access to the FTS2000 networks can be accomplished through industry-standard long distance carrier presubscription where available, and/or by using the FTS2000 toll free access numbers and an FTS2000 credit card. If these techniques are not used, long distance services will still be provided, however, the long distance charges will appear on your FWTS bill. You can place local or long-distance calls within the United Sates and Canada as long as you are within a cellular service area.

What are "special" calls?

Long distance (within the United States) and calls to directory assistance may be made by following the same procedures used when making these types of calls from your home or office. Collect calls and third-party calls cannot be charged to your cellular telephone number.

What if my phone is stolen?

If your phone is stolen you should immediately call the Federal Wireless Service Center at 1-888-333-9473 and report the phone as stolen. This will prevent any fraudulent use from being billed to you. Other cellular carriers throughout the country will then be requested to deny network access to this phone. The Federal Wireless Service Center will be able to help you get a new phone and get service re-established using your old telephone number. You should then report the theft to your local police department. Request case number and a copy of the police for you records report.

What happens if I move to another town or state? What should I do?

All FCC approved cellular telephones can be used on all cellular systems throughout the country. Before you move to a new area, contact the Federal Wireless Service Center at 1-888-9473 for assistance in transferring your cellular service.