A group of satellites providing location info is called a constellation. These satellites broadcast the signal to the earth. Receivers calculate the difference in timing of the received signals from various satellites to give the exact location. Signals store the position of broadcasting satellites. GPS is one of the oldest such constellations. It is called global because the receiver can access the signal from the constellation anywhere in the world. There is also a Japanese regional system QZSS that covers only Asia and Oceania. Tracking system requires at least 4 satellites to receive the signal that enables to calculate elevation, latitude, and longitude. It is always good to see the maximum number of satellites for a receiver to enhance the accuracy. Also, Both GPS & GLONASS are used in many public devices like
vehicle navigation devices, location trackers, smartphones, & even in sports like these golf GPS watches.
The global positioning system (GPS) is the USA navigation system encompassing at least 31 operational GPS satellites. It gives very high accuracy which became fully operational in 1994. Satellites transfer the microwave radio signal which consists three to four codes and a navigation message. GPS works on CDMA principal and PRN code of every satellite is distinct. It was originally developed for the military system and afterward, it was made for the public. For military advantages, there are two positioning and timing services, the Precise Positioning Service (PPS) for military use and the Standard Positioning Service (SPS) for everyone. The U.S. government is spending a multi-billion dollar on the performance and modernization of the program.
We take the GPS granted and it is essential for devices such as cell phones, watches, weather forecasting, and computers, etc. Most of the industries rely on the accuracy of GPS. GPS controls the air, sea, and road transportation systems. GPS is playing an important role in providing the data that was never available in terms of quality and accuracy. It enables to determine the movement of the Arctic ice sheets and volcanic activity. It has changed the world with today’s smartphones as a means to facilitate the navigation for the end user. GPS helps in managing the traffic through real-time data transfer. GPS works in all-weather condition. It does not have any subscription fee and GPS receiver is accurate within 15 meters.
GLONASS is a Russian Satellite system. This program consumed a lot of budget in 2010 and it was considered to be the most expensive program of the Russian Federal Space Agency. It is a fully operational radio-based navigation system. It actually complements the GPS and gives better accuracy at high altitudes. Various versions of GLONASS are outlined below:
- GLONASS M
- GLONASS K
- GLONASS K2
- GLONASS KM
China is also working on a constellation system of 35 satellites called the BeiDou Navigation Satellite System claiming to give more capabilities than GPS.
The Indian Space Research Organization has already placed four satellites out of 7 to accomplish IRNSS or Indian Regional Navigation Satellite System.
Using both GPS and GLONASS, you get an opportunity for the maximum coverage because you are targeting the 55 satellites that span your sky. It is most likely you will pick the signal. It is also important to use both GPS and GLONASS with your tracking device because if GPS is not able to work on some spots GLONASS will relay the information in order to give you the required signal.
GPS has high accuracy rates when compared to GLONASS. When tests are conducted to check the accuracy of both of the satellite navigation systems, GPS always supersedes to give the best result. There is an advancement in GLONASS work, but latest data proved GPS was ahead by 6 feet. GLONASS stations are mostly in Brazil and Antartica and GPS stations are located worldwide that makes the real difference.
GLONASS vs GPS
In one specific way, GLONASS is ahead of GPS. It performs well at high altitudes, where GPS gets the hindrance. Thus, it plays as an excellent alternative to GPS in some cases. We can also place an antenna that can receive signals from both GLONASS and GPS if required.
Also, many latest GPS device manufacturers started rolling devices with both GPS & GLONASS like handheld GPS devices that are used for hiking, hunting, and other outdoor activities. we could expect more devices that support both the positioning systems in the future.
GPS happens to be around for a long time and found to more mature. Therefore, it is famous worldwide. Most consumer products are equipped with this technology and supersede the GLONASS in many places. Anyway, GLONASS is striving to come closer to GPS in the near future and lots of work is under development to reach a full operational capability. Russia GLONASS along with China’s Baidu and Europe’s Galileo navigation satellites are threatening the US monopoly on the navigation system. Many commercials manufacture such Sony and HTC use the GLONASS chips in their product. Car navigator SGK-70 used the GLONASS. It is still nowhere close to GPS but GLONASS alongside GPS will always increase the accuracy.