Observant field units engage in two quite different modes of communication.
Communications with Observant Global
A 3G (third generation cellular communications) network is used to send data to the Observant Global Cloud. All of the Observant systems incorporate 3G-connected field units to provide data to customers regardless of their location.
Communications Between Units
Sometimes field units will act as nodes (Field Units can be configured to act as nodes), sending their information to another unit, which will relay it to the Observant Global Cloud. In these cases, the data is typically transmitted using a one Watt, 900 MHz, spread spectrum radio.
Remedies for Some Common Communication Issues
Although many factors affect communications between field units (and from units to the Cloud), here we will discuss solutions for just a few potential sources of trouble.
- Just as organ pipes must be tuned to resonate at the proper pitch, antennas are designed to be most effective at specific frequencies. Always verify that the GPS antenna (GPS) and the 900 MHz antenna (XG) are plugged into the correct ports on the C3 module. Without the proper antenna, a field unit will not be able to communicate.
- The antenna should always be mounted in a vertical orientation (pointing to the sky).
- The signal that travels from the radio to the antenna should be provided using only cables that have been designed for that purpose.
- Care must be taken to avoid twisting, crimping, or folding any antenna cable.
- Never allow moisture to seep into an antenna cable.
- When a C3 has both a 3G and 900 MHz antenna, the antennas should be mounted with at least two feet (61 cm) of vertical separation and three feet (92 cm) of horizontal separation. This spacing will prevent mutual interference and ensure that both 3G and 900MHz antennas perform at maximum efficiency.
- The communication signals (especially those between a pair C3 units) will work best when there is a direct, unobstructed path involved. This should always be taken into consideration when installing field units.
- The presence of large buildings, hills, vegetation, or any other obstructions between units can cause significant problems.
- Any structures with large amounts of metal are particularly troublesome.
- Any substantial metal object will exert a significant influence when directly adjacent to an antenna. This fact must be taken into consideration whenever mounting antennas. Antennas will always work best mounted on the tops of poles, in the clear.
- Never install antenna immediately next to a metal building (even if there is a line of sight to the field unit with which it is communicating).