Adaptive Scan Trigger Timer for WLAN Power Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Mobile communication devices in wireless local area networks (WLANs) face increased battery power consumption due to regular background scanning for wireless access points, which affects battery life.
Innovation Solution
A method is implemented where a mobile communication device maintains a list of scan trigger threshold values for each wireless access point, based on the last-sampled communication signal quality, and adjusts scanning operations accordingly, performing scans only when the signal quality is below the threshold, thereby reducing power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If regular background scanning is performed to identify wireless access points, then communication reliability is improved, but battery power consumption increases
Solution Approach 1:
The patent applies dynamics by making the scanning frequency adaptive rather than fixed. The mobile device dynamically adjusts scanning intervals based on signal quality measurements, performing scans more frequently when signal quality degrades and less frequently when signal quality is good, thereby resolving the contradiction between maintaining communication reliability and reducing power consumption
Solution Approach 2:
The patent changes the parameter of scanning frequency based on signal quality conditions. By monitoring communication signal quality and adjusting the scanning interval parameter accordingly, the system optimizes the balance between detection reliability and energy consumption, scanning only when necessary rather than at fixed regular intervals
2Measurement precision
If scanning operations are performed frequently to ensure reliable communication, then detection accuracy is improved, but power consumption increases
Solution Approach 1:
The patent implements feedback by continuously monitoring communication signal quality and using this information to control scanning operations. The system measures signal quality, compares it against thresholds, and adjusts scanning behavior accordingly, ensuring detection accuracy is maintained only when necessary while reducing unnecessary scans that consume power
3Use of energy by moving object
If the mobile device refrains from scanning to conserve battery power, then power consumption is reduced, but communication reliability may deteriorate
Solution Approach 1:
The system dynamically adjusts scanning frequency based on real-time signal quality conditions rather than using a fixed schedule. When signal quality is good, scanning is reduced to conserve power; when signal quality degrades below thresholds, scanning frequency increases automatically to maintain communication reliability, thus resolving the contradiction adaptively
Data Source
Figure 1
Figure 2
Figure 3
AI summary
One illustrative method for reducing power consumption in a mobile communication device of a wireless local area network (WLAN) involves the steps of identifying a communication signal quality value between the mobile device and a wireless access point of the WLAN with which the mobile device is currently associated; determining an initial timer value based on a predefined relationship with the communication signal quality value where, as the communication signal quality value decreases, the initial timer value correspondingly decreases; initializing a scan trigger timer with the initial timer value and running the scan trigger timer; and upon expiration of the scan trigger timer: causing a scanning operation to be performed for identifying one or more wireless access points in a coverage region; and repeating the acts of identifying, determining, initializing and running the scan trigger timer, and causing the scanning operation to be performed. Preferably, the mobile device operates to refrain from performing scanning operations altogether when the communication signal quality value is greater than a scan trigger threshold value. The scan trigger threshold value may be derived from or calculated based on a previously-received or last-sampled communication signal quality value of the wireless access point sampled at a time when the mobile device chose to reassociate with a different wireless access point of the WLAN.