White Bear Technologies RoamEO GPS Pet Location System User Manual

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GPS Basics

The Global Positioning System (GPS) was launched in 1995 by the

United States Defense Department. Twenty-four satellites orbit at 10,900

nautical miles above the Earth, passing overhead twice daily. At least

four of these satellites are in view nearly anywhere on the Earth at

all times.

GPS requires signal reception from three satellites in order to

determine a latitude and longitude position, known as a 2D fix. Four

satellites are needed to determine position and elevation. This is a 3D

fix. In 2003, in order to provide an additional degree of accuracy to

GPS, the Federal Aviation Administration developed a program called

Wide Area Augmentation System (WAAS) that complements GPS.

WAAS is not always available to GPS users because of the position

of the satellites. RoamEO will automatically receive WAAS signals,

if available.

Please remember: for GPS to work effectively, it must have a

clear view of the satellites in the sky in order to receive their

signals. Unlike television or radio signals, GPS works at very high

frequencies. As a result, GPS reception can be easily effected by

tree foliage, buildings, your body, and any other cover that blocks

the sky.

To help achieve the maximum per formance from RoamEO,

we recommend:


If possible, power up RoamEO outdoors.


If powering up RoamEO outdoors, maintain some distance from

buildings and stay out from under foliage if possible. Af ter gaining

an initial GPS lock, RoamEO will probably maintain a lock even if

operating under these conditions.


If indoors, it may require a few minutes to acquire a GPS lock. To

improve your ability to gain a GPS fix, stand as close to a window

as possible so that RoamEO has at least a par tial view of the sky.

It is unlikely that you will be able to achieve a GPS fix from an

interior room in the house or the basement.

You can check the status of the GPS reception on the GPS Receiver

Toolbar. For more detailed information on the GPS status, refer to the

GPS Status Screen.