Received Signal Strength Indicator (RSSI) is a measurement of the Radio Frequency (RF) power present in a received radio signal at the mobile device. It is generally expressed in dBm and the best throughput comes from placing the device in an area with the highest RSSI.
The Cellular page on the Status: Statistics screen shows the current state of the cellular modem including the RRSI. This screen will display automatically on an ACM5000-Gx, ACM5500-Gx. ACM5500-Lx, IM4200-Gx or IM7200-Lx.
-100 dbm or less = Unacceptable coverage -99 dbm to –90 dbm = Weak Coverage -89 dbm to – 70 dbm = Medium to High Coverage -69 dbm or greater = Strong Coverage
Maximizing cellular signal strength
Your antenna placement can drastically increase the signal strength:
Keep the antenna and antenna cable away from AC wiring and other interference (such as other electrical or radio devices)
Select the optimum placement for the antenna (e.g. close to an exterior window or to a higher point in the building, on top of tall cabinets etc)
Move the device to a side of the building that faces the carriers cellular tower
It may be useful to undertake a signal strength site survey to profile your site prior to installation. A basic site survey can be done using a standard cell phone