1. The radio card automatically tunes to each RF channel, listens for a period of time, and records information it finds regarding access points on each channel.
2. By default, each access point transmits a beacon frame every 100 milliseconds on a specific RF channel, which the administrator configures.
3. While tuned to a specific channel, the radio card receives these beacon frames if an access point is in range and transmitting on that channel.
4. The radio card records the signal strength of the beacon frame and continues to scan other channels.
5. After scanning each of the RF channels, the radio card makes a decision about the access point with which it will associate.
In general, the radio card chooses the access point with the strongest beacon signal. Some radio vendors might include other parameters, such as noise levels and utilization, when making this decision.