Active WLAN Scanning via Probe ACK Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless local area network (WLAN) systems, active scanning for access points is inefficient due to the large number of probe request and response frames generated, leading to prolonged waiting times for terminals to receive probe response frames, especially in environments with multiple terminals and access points.
Innovation Solution
The method involves transmitting a prior probe request frame across any channel, acquiring probe ACK frames, setting a maximum waiting time based on the number of ACK frames received, and performing active scanning on that channel for the specified time, allowing for early detection of access point presence and reducing waiting time by predicting the number of probe response frames and assessing wireless signal quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a terminal transmits probe request frames to scan access points in an environment with multiple terminals and access points, then the terminal can detect the presence of access points, but a large number of probe request and response frames are generated occupying wireless channels and causing prolonged waiting times
Solution Approach 1:
The terminal transmits a prior probe request frame before the actual probe request frame to preliminarily check access point presence and acquire probe ACK frames. This preliminary action allows the terminal to predict the number of probe response frames and set an appropriate maximum waiting time, avoiding unnecessary prolonged waiting in environments with multiple access points
Solution Approach 2:
The terminal acquires probe ACK frames as feedback from access points in response to the prior probe request frame. By analyzing the number of probe ACK frames received, the terminal can predict the number of probe response frames and adjust the maximum waiting time accordingly, optimizing the scanning process
2Productivity
If terminals continuously wait for probe response frames to ensure complete scanning, then scanning completeness is maintained, but channel occupancy time increases and scanning efficiency decreases
Solution Approach 1:
The terminal performs a preliminary check by transmitting a prior probe request frame and acquiring probe ACK frames before the main scanning process. This preliminary action provides information about the number of access points present, allowing the terminal to set an optimized maximum waiting time that balances scanning completeness with efficiency, avoiding unnecessary prolonged channel occupancy
Solution Approach 2:
The maximum waiting time is dynamically adjusted based on the number of probe ACK frames received. When fewer access points are detected, the waiting time is reduced, optimizing channel usage. This dynamic adjustment allows the scanning process to adapt to different network environments and maintain high efficiency across varying conditions
Data Source
AI summary
An active search method in a wireless LAN system is disclosed. The active search method comprises the steps of: transmitting, through an arbitrary channel, a preceding probe request frame for confirming the existence of an access point; acquiring, from at least one access point, a probe ACK frame that is a response to the preceding probe request frame; setting a maximum waiting time on the basis of the number of probe ACK frames; and performing an active search for an access point in the arbitrary channel for the maximum waiting time. Therefore, the waiting time for receiving a probe response frame can be reduced.