Mobile Station Frequency Sync with Dynamic AFC Intervals
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing mobile station frequency synchronization methods fail to efficiently manage temperature-related and movement-induced frequency variations, leading to frequent and energy-consuming receiving operations, and often require costly, temperature-compensated reference-frequency oscillators.
Innovation Solution
The method adjusts the length of AFC measuring intervals based on predicted temperature and movement-related frequency variations, allowing for longer intervals when variations are small and shorter intervals in critical conditions, using an inexpensive, non-temperature-compensated reference-frequency oscillator, and separates temperature and movement-related frequency errors for precise control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If frequent receiving operations are performed to measure frequency variation, then frequency synchronization accuracy is improved, but energy consumption increases
Solution Approach 1:
The AFC measuring interval is made dynamic rather than fixed. The interval length is continuously adjusted based on the current frequency variation rate and predicted future variations. When frequency is stable, intervals are extended to save energy; when variations are detected, intervals are shortened to maintain accuracy. This dynamic adaptation resolves the contradiction between measurement precision and energy consumption.
Solution Approach 2:
The system performs preliminary analysis of frequency variation patterns using stored characteristic curves that represent temperature-related and movement-related frequency behaviors. By predicting future frequency variations based on current conditions (temperature, movement state), the system can proactively adjust the AFC measuring interval before actual frequency drift occurs, optimizing both accuracy and energy usage in advance.
2Stability of the object's composition
If temperature-compensated reference-frequency oscillators are used, then frequency stability is improved, but device cost increases
Solution Approach 1:
The patent replaces the mechanical/physical temperature compensation mechanism (hardware-based temperature-compensated oscillators) with a software-based solution. Instead of using expensive oscillators with physical temperature compensation circuits, the system uses stored characteristic curves and computational algorithms to predict and compensate for temperature-related frequency variations, achieving the same stability at lower cost.
Solution Approach 2:
The invention substitutes expensive, complex temperature-compensated oscillator hardware with inexpensive, simple oscillators combined with software compensation. The system uses cheap oscillators whose frequency drift is corrected through algorithmic prediction based on temperature characteristics, effectively replacing costly hardware with affordable components plus processing.
3Measurement precision
If AFC measuring intervals are kept short, then frequency variation detection accuracy is improved, but the number of receiving operations increases
Solution Approach 1:
The AFC measuring interval is dynamically adjusted based on the current frequency variation rate and predicted future variations. When the frequency is stable and no significant variations are expected, the interval is extended, reducing the number of receiving operations. When variations are detected or predicted, the interval is shortened to maintain detection accuracy. This dynamic approach optimizes the balance between measurement precision and operational efficiency.
Solution Approach 2:
The system changes the parameter of AFC measuring interval length based on operating conditions. Instead of using a fixed interval, the interval duration is modified according to the measured frequency variation rate and the predicted temperature/movement conditions. This parameter adaptation allows the system to reduce the number of receiving operations during stable periods while maintaining high detection accuracy during critical periods.
4Reliability
If receiving operations are performed frequently, then network synchronization is maintained, but standby time is reduced
Solution Approach 1:
The system performs preliminary prediction of frequency variations using stored characteristic curves that represent temperature-related and movement-related frequency behaviors. By analyzing current temperature and movement conditions, the system predicts whether significant frequency drift will occur in the near future. This allows the mobile station to extend its standby time between receiving operations when variations are not expected, while still maintaining synchronization by performing receiving operations promptly when critical variations are predicted.
Solution Approach 2:
The standby time is made dynamic rather than fixed. The system continuously monitors frequency variation rates and adjusts the timing of receiving operations accordingly. When frequency is stable and variations are minimal, standby time is extended to maximize battery efficiency. When variations are detected or predicted, the system reduces standby time and initiates receiving operations earlier to maintain network synchronization, thus adapting to changing conditions.
Data Source
AI summary
In a method for synchronizing a mobile station with the base station in a mobile communication system, a reference-frequency oscillator is re-adjusted. To enable an inexpensive reference-frequency oscillator of simple construction to be used, the frequency variations resulting from a change in the temperature of the mobile station and a change in its location are determined and/or predicted separately. When the frequency variations are large, the mobile station is synchronized with the base station more frequently than when they are small.