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Cellular Phones - Operating Characteristics

File In Section: 08 Body and Accessories

Bulletin No.: 01-08-46-004

Date: August, 2001

INFORMATION

Subject:
Vehicle Integration of Cellular Phones and Normal Operating Characteristics

Models:
2002 and Prior Passenger Cars and Trucks

What is a Cell Phone

The cellular telephone is a small portable device which allows communication with others from remote or moving locations using Ultra High Frequency (UHF) radio signals.

Important:
All communication devices which use air waves as a means of communication are regulated by the Federal Communication Commission (FCC) (the Canadian Radio-Television and Telecommunications Commission (CRTC) in Canada). These regulations cover cell phones and, as such, the handheld, all-in-one cell phone cannot exceed 0.6 watts in output.

Currently, cell phones are available in three different styles:

A bag phone with a handheld receiver attached to a module with an antenna by way of a cord, typically plugged into a cigarette lighter receptacle in the vehicle and placed on the floor: A three watt device. A self-contained handheld device with antenna attached directly to the device with an internal antenna and battery: A 0.6 watt device using an analog signal.

A self-contained handheld device with antenna attached directly to the device with an internal antenna and battery: A 0.6 waif device using a digital signal.

Cell Phone Characteristics

The cell phone uses air waves to transmit information.

The following are some of the factors that influence its usage:

^ Cell phone UHF signals are like FM radio signals. They are low level line of sight signals as compared to the AM signal which is bounced off the ionosphere. Tall buildings, hills and other natural and man-made obstacles interfere with cellular phone UHF signals.

^ Each cell site (towers) service area is a circle. If the provider has not placed the towers perfectly, there will be holes which will be encountered and service will be unavailable.

^ Each cell site will service a radius of approximately 16 km (10 mi) from the site, with a three watt bag phone, and 10 km (6 mi) with a handheld 0.6 watt phone.

^ Each cell site is restricted as to the number of individual calls it may handle at one time, about 800 with current technology. Typically, at peak times (rush hour in the morning and evening). the number of customers using the cell phone on the commute saturates the cell site.