Cellular 3G CDMA history table. The history of RSSI are
carried in an octet of string. Each octet in the octet string
has a value from 0 to 150 and the 255 value is reserved to
indicate an uninitialized (Invalid) value. The format of the
octet string with n octets is as following:
[ octet 0 is latest,
octet 1 is latest-1,
.
.
octet n-2 is oldest-1,
octet n-1 is oldest ]
To convert the provided value into dBm the following formula
should be used:
dBm = (-1)*value;