Signal Strength signal in Windows
• Using a utility in wireless adapters : Some manufacturers of wireless networking equipment and laptops (such as Linksys, IBM) provide software applications with hardware, possibly monitor weak strength of wireless signal. These applications often record weak strength and signal quality in a ratio of 0 to 100%.
For example, an Excellent connection with a full 5 bar ratio in Windows XP can be displayed in ThinkVantage Access Connection connections as Excellent with a percentage at all points from 80 to 100%. This ratio is based on the radio signal density maintained by the wireless network adapter in dB (de-decibels).
• Wi-Fi positioning devices : similarly, a Wi-Fi positioning device is built to determine signal strength near wireless access points. Most Wi-Fi routers use 4 to 6 LED indicators to display signal strength in 'bar units' (ie vertical bars) similar to Microsoft Windows utilities. But unlike the above, Wi-Fi positioning devices do not measure the weak strength of real connections, they only predict.
Note that the different tools above will sometimes give slightly different results. For example, on the same connection, a wireless adapter utility can evaluate the signal strength of the signal as '82% 'and another utility that has a '80%' result, and a locator Wi-Fi can display 3 light bars while others show 4 of 5 bars. Different causes are because each utility has a way of collecting patterns and limiting the amount of time they use differently to divide the average and give the overall rate.