Interpreting Signal Strength for Bullhorn Units

How do I interpret numeric RSSI (Receive Signal Strength Indicator) Values for Bullhorn remote monitoring units in the Bullhorn Tools software?

  1. Digital Cellular Network (Units such as the AMR6-GSM, APM4AM-GSM, and SDT16-GSM)— use a negative scale, with numbers closer to zero indicating a stronger signal. For example, –80dB is a stronger signal than –100dB. Successful communication requires a minimum RSSI of –88dB. *

  2. SkyWave Inmarsat Satellite Network (Units such as the AMR6-SAT, APM4AMSAT, and RM4010) — use a scale from 0.00dB to 50.00dB. Readings above 14dB indicate strong signal. Readings below 14dB indicate an inability to communicate with the satellite. **

  3. Orbcomm Satellite Network (Bullhorn units such as the AMR6-ORB, APM4AM-ORB, SDT16-ORB, and RM4020) — use a scale from 0.0 to 15.0. Readings above 12 indicate strong signal. Readings below 8 indicate inability to communicate with the satellite. **

Notes:

* Because of inherent characteristics of radio frequencies, digital cellular service may be limited or packet transmissions may be incomplete for a variety of reasons. Actual coverage depends on system availability, terrain, weather, signal strength, customer equipment and other factors. Service may be temporarily limited or interrupted due to system capacity limitations and system repairs, modifications or upgrades. Every attempt has been made to ensure the highest level of system availability and reliability. However, the factors previously mentioned may have an impact on the provided service.

** Footprint anomalies, extreme weather conditions, and intermittent obstacles on the horizon can cause communications failure with the SkyWave Inmarsat D+ or Orbcomm satellite. For the SkyWave satellite, a successful look angle (azimuth and elevation angle) does not necessarily mean reliable satellite coverage. Low look angles (less than 15 degrees elevation) may also be subject to fading due to rain, snow, clouds, and other weather conditions. Every attempt has been made to ensure the highest level of system availability and reliability. However the factors previously mentioned may have an impact on the provided service.