Network Signal Strength Indicator
Mobile Network Signal Strength
To successfully send SMS messages the VanSecure control unit needs a certain minimum signal strength. On the mobile phone the signal strength between it and the network is often shown as a bar chart. The VanSecure control unit communicates its current network signal strength to the mobile phone, and the mobile phone will display this value on the battery voltage indicator button when you tap this button. The button reverts to the battery voltage display after a short delay.
The signal strength is given in dBm (deciBels of a milliWatt) and is always a negative number. The larger he number the weaker the signal is and the closer it is to zero the stronger the signal. Antenna powers of less than -90dBm (from -90dBm towards -115dBm) will produce reliable SMS transmissions.