correct Signal Strength parameter to display it in GUI ?
 

I have 3G USB dongle connected to my LFS system. I'm able to get the signal strength information(RSSI, BER) through 'AT+CSQ' AT command. I want to display this information in GUI(Graphical User Interface). What is the valid method to show this information ? I mean should i convert RSSI to dbM and show in GUI? What is the best way to show accurate signal strength in GUI? I have no clue on how to proceed further.

People expect the bar to show a percentage.

RSSI isn't strictly defined, some chipsets (e.g. Atheros) have a 7-bit range, 0-127. Some of them (e.g. Cisco) return 0-100, etc.

So just find out what the range is for this chipset, convert it to a percentage if it's not already 0-100, and fill a bar appropriately. For added flair, change the color of the bar based on the % value.