WLAN Filter Response Shift Compensation for 5 GHz and 6 GHz Coexistence
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Collocated radios operating in the 5 GHz and 6 GHz Wi-Fi bands face interference and coexistence issues due to narrow bandgaps, leading to attenuation and signal degradation, especially with temperature-sensitive filters that shift frequency responses, affecting channel availability and throughput.
Innovation Solution
The implementation of digital pre-distortion (DPD) techniques and PHY Protocol Data Unit (PPDU) scheduling schemes to compensate for filter frequency response shifts, ensuring proper frequency domain coexistence by adjusting signal amplitudes and channel bandwidths, thereby mitigating interference and maintaining channel reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If digital pre-distortion techniques are applied to compensate for filter frequency response shifts, then channel reliability and throughput are maintained, but device complexity increases
Solution Approach 1:
The patent applies digital pre-distortion (DPD) techniques that pre-compensate for filter frequency response shifts before signals are transmitted or received. By performing the compensation action in advance (pre-distortion), the system maintains channel reliability and throughput despite temperature-induced filter drift, without requiring real-time complex adjustments during operation.
Solution Approach 2:
The system dynamically adjusts signal parameters (amplitude, phase, frequency) through DPD to counteract filter response changes. By changing the signal parameters in advance based on predicted filter behavior at different temperatures, the system maintains reliable communication while adapting to environmental conditions.
2Productivity
If narrow bandgaps are used between 5 GHz and 6 GHz radios to increase channel availability, then spectrum utilization improves, but interference and signal degradation increase
Solution Approach 1:
The patent converts the potentially harmful effect of narrow bandgaps (which cause interference) into a benefit by using the known filter response characteristics to pre-distort signals. The interference that would normally degrade signals is actually used as the basis for creating compensation algorithms, turning the harmful frequency response shifts into useful information for maintaining signal quality.
Solution Approach 2:
The DPD processing acts as an intermediary between the narrow bandgap configuration and the final signal transmission. By inserting this pre-distortion stage, the system mediates the interaction between closely spaced frequencies, allowing narrow bandgaps to be used for increased channel availability while preventing the expected interference and signal degradation.
3Volume of moving object
If temperature-sensitive filters are used in collocated radios, then device miniaturization is achieved, but frequency response stability deteriorates
Solution Approach 1:
The system implements a feedback mechanism where the known temperature characteristics of the filters are used to determine appropriate pre-distortion parameters. By monitoring or predicting temperature changes and adjusting the DPD parameters accordingly, the system maintains frequency response stability despite using compact temperature-sensitive filters in collocated radio designs.
Data Source
AI summary
Systems and techniques are described that are directed to filter frequency response shift compensation, including compensating for shifting in the rejection band of the filter. Compensation for the shifting in the rejection band can include applying a pre-distortion to attenuate edge resource units (RUs), and applying PHY Protocol Data Unit (PPDU) scheduling schemes. For example, a PPDU scheduling scheme reduce bandwidth in the channel, thereby dropping the out of band RUs. Front ends provide feedback to a respective radio, which allows that radio to apply the appropriate pre-distortion. The front ends can include one or more filters enabling frequency domain coexistence between collocated radios operating in the differing Wi-Fi bands, and a coupler that provides the feedback indicating the frequency response shift to a radio. The radio can then apply a digital pre-distortion to compensate for the shifting in the rejection band.