Wireless Channel Selection via Interference Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional wireless communication apparatuses face difficulties in detecting the periodicity of interfering waves from microwave ovens, especially when these waves are mixed with other signals, leading to potential channel overlap and reduced communication efficiency.
Innovation Solution
A channel determination method that involves switching between reception frequencies, detecting a predetermined preamble, and using a counter to enable or disable channels based on signal strength thresholds, thereby avoiding channels with strong interfering signals and minimizing interference.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional carrier sensing is used to detect interfering waves, then simple detection is achieved, but periodicity of microwave oven interfering waves cannot be detected when mixed with other signals
Solution Approach 1:
The patent segments the detection process into multiple independent counters, each dedicated to detecting specific characteristics of interfering waves (preamble presence, signal strength threshold exceedance, duration). This segmentation allows precise detection of microwave oven periodicity by accumulating evidence across multiple detection dimensions without requiring a single complex detection mechanism.
Solution Approach 2:
The patent performs preliminary actions by pre-defining detection criteria (preamble patterns, threshold levels, counter increment/decrement rules) before actual signal detection begins. This preliminary setup enables the system to automatically recognize and respond to periodic interfering waves when they occur, without requiring real-time complex analysis.
2Reliability
If channels are disabled to avoid interference, then communication reliability is improved, but available channels for communication are reduced
Solution Approach 1:
The patent implements dynamic channel management where channels are not permanently disabled but temporarily restricted based on real-time detection of periodic interfering waves. The channel restriction is dynamically adjusted according to the detected interference pattern, allowing channels to be reused when interference is absent while maintaining reliability when interference is present.
Solution Approach 2:
The patent changes the parameter of channel availability based on detected interference characteristics. Instead of fixed channel allocation, the system dynamically modifies channel status (enabled/disabled) according to the presence and periodicity of interfering waves, optimizing both reliability and channel utilization through parameter adaptation.
3Object-affected harmful factors
If strict carrier sensing threshold is applied, then interference avoidance is improved, but transmission opportunities are lost when interference level is acceptable
Solution Approach 1:
The patent applies partial action by using different detection thresholds for different types of interference. Instead of applying a single strict threshold to all signals, the system uses lenient thresholds for non-periodic signals (allowing transmission) and strict thresholds for periodic microwave oven signals (blocking transmission), achieving optimal balance between interference avoidance and transmission efficiency.
Solution Approach 2:
The patent implements feedback mechanisms where the detected signal characteristics (preamble presence, strength, duration, periodicity) feed back into the transmission decision process. This feedback loop allows the system to adaptively adjust transmission behavior based on actual interference conditions, preventing transmission only when necessary while allowing transmission when interference is acceptable.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A channel determination method is disclosed that can avoid performance deterioration caused by interference even in a situation in which radio waves from other communication apparatuses including a microwave oven using the same frequency band are mixed. This method detects a predetermined preamble in a received signal when performing carrier sensing while switching between reception frequencies of a receiving section. The method examines, using a counter, how often electric field strength exceeds a predetermined threshold for each channel during the carrier sensing, disables, upon detecting a signal from another 802.11 apparatus, a channel from which the signal is detected and also disables a channel for which the counter shows a count value exceeding the threshold.