Specifications

Equipment Check

Prior to leaving the office to perform your survey, be sure to

perform a thorough check of your GPS equipment:

1. Check through the ProMark3 system to ensure all compo-

nents are present to successfully perform the survey.

2. Check to ensure that you have sufficient battery power to

complete the survey. Bring along a spare set of batteries

for insurance.

3. Bring along a copy of your network design and printout of

the satellite availability and distribution analysis. These

will be needed throughout the course of your survey.

With the equipment check completed, it’s time to move to the

field to perform your survey.

Site Selection

Proper site selection of performing GPS data collection is crit-

ical to the success of your survey. Not all sites are appropriate

for GPS data collection.

GPS depends on reception of radio signals transmitted by sat-

ellites approximately 21,000 km from Earth. Being of rela-

tively high frequency and low power, these signals are not very

effective at penetrating through objects that may obstruct the

line-of-sight between the satellites and the GPS receiver.

Virtually any object that lies in the path between the GPS re-

ceiver and the satellites will be detrimental to the operation of

the system. Some objects, such as buildings, will completely

block out the satellite signals. Therefore, GPS can not be used

indoors.