Electromax International, Inc.
"Global Tracker"

We have provided a glossary of terms to help our customers understand the technologies used by our products.

What is GSM

What is GPS

What is a SIM Card

What is GSM?
GSM (Global System for Mobile Communications) is a second-generation digital mobile telephone standard using a variation of Time Division Multiple Access (TDMA). It is the most widely used of the three digital wireless telephone technologies - CDMA (Code Division Multiple Access), GSM and TDMA. GSM digitizes and compresses voice data, then sends it down a channel with two other streams of user data, each in its own time slot. It operates at either the 900, 1800 or 1,900MHz frequency bands.

GSM was initially developed as a pan-European collaboration, intended to enable mobile roaming between member countries. As of March 2003, GSM digital wireless services were offered in some form in over 193 countries. In June 2002, about 69% of all digital mobile subscriptions in the world used GSM phones on GSM networks.

What is GPS?
GPS - (Global Positioning System) is a constellation of satellites that orbit the earth twice a day, transmitting precise time and position (latitude, longitude and altitude) information. With a GPS receiver, users can determine their location anywhere on the Earth. Position and navigation information is vital to a broad range of professional and personal activities, including hiking, hunting, camping, boating, surveying, aviation, national defense, vehicle tracking, navigation and more.

The complete system consists of 24 satellites orbiting about 12,000 miles above the Earth, and five ground stations to monitor and manage the satellite constellation. These satellites provide 24-hour-a-day coverage for both two-and three- dimensional positioning anywhere on Earth.

Development of the $10 billion GPS satellite navigation system was begun in the 1970s by the US Department of Defense, which continues to manage the system, to provide continuous, worldwide positioning and navigation data to US military forces around the globe. However, GPS has an even broader civilian, commercial application. To meet these needs, GPS offers two levels of service, one for civilian access and the second encrypted for exclusive military use.

The GPS signals are available to an unlimited number of users simultaneously, and there is no charge for using the GPS Satellites either.

The basis of GPS technology is precise time and position information. Using atomic clocks and location data, each satellite continuously broadcast the time and its position. A GPS receiver receives these signals, listening to three or more satellites at once, to determine the users position on earth.

By measuring the time interval between the transmission and the reception of a satellite signal, the GPS receiver calculates the user and each satellite. Using the distance measurements of at least three satellites in an algorithm computation, the GPS receiver arrives at an accurate position fix. Information must be received from three satellites in order to obtain two-dimensional fixes(latitude and longitude), and four satellites are required for three-dimensional positioning (latitude, longitude and altitude).

Under normal conditions, the GPS signal will provide a civilian user an accuracy of better than 15 meters (50 feet). However, using a technique called differential GPS (DGPS), the user can increase the overall accuracy of the GPS receiver to approximately 1-3 meters. With DGPS, one GPS receiver unit is placed in a known location and the position information from that receiver is used to calculate correction in the position data transmitted to other GPS receivers in the area. The resulting real-time accuracy is in the 10 foot range. Sub-meter accuracy can be obtained by using DGPS and post-processing calculations in static positioning.

What is a SIM card?
The SIM (Subscriber Identity Module) is a chip card, the size of a first class postage stamp. It is a key element in over 600 million GSM mobile phones - representing about 70 percent of the mobile handset market.

A SIM is actually a tiny computer chip that gives a cellular device it's unique phone number. It has memory (for data and applications), a processor and the ability to interact with the user. Current SIMs typically have 16 to 64 kb of memory, which provides plenty of room for storing hundreds of personal phone numbers, text messages and other data.

Many of our customers prefer to use prepaid time because purchasing the SIM card can be done anonymously. SIM cards generally cost $45 and come with 40 minutes of time depending on your area. Often you can buy time for as little as $10 for up to 100 minutes. Using prepaid time, professional real-time tracking is possible for as little as $0.11 a day!