Inter-channel Bias Calibration for GLONASS Receivers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
GLONASS inter-channel biases pose a significant challenge to achieving centimeter and sub-centimeter accuracy in navigation satellite systems, as they vary with receiver design, temperature, and component differences, leading to inaccurate positioning when not properly accounted for.
Innovation Solution
A calibration module generates a reference signal to measure bias delay through the front-end circuitry of a navigation receiver, producing a correction signal to reduce inter-channel bias, which can include phase and range corrections, implemented in hardware, firmware, or software, and is adaptable to changes over time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If GLONASS satellites are used for positioning, then the number of available satellites increases, but inter-channel biases degrade position accuracy
Solution Approach 1:
The patent applies parameter changes by dynamically adjusting the inter-channel bias correction values based on measured temperature data. The system changes the bias parameters in real-time to compensate for temperature-induced variations, thereby maintaining position accuracy while utilizing multiple GLONASS satellites across different frequency channels.
Solution Approach 2:
The patent implements feedback by continuously measuring the temperature of the receiver's front-end circuitry and using this information to update the inter-channel bias corrections. This closed-loop feedback mechanism ensures that the bias corrections remain accurate despite environmental changes, allowing reliable use of GLONASS satellites for precision positioning.
2Device complexity
If inter-channel biases are ignored to simplify processing, then device complexity is reduced, but positioning accuracy deteriorates
Solution Approach 1:
The patent applies preliminary action by pre-calculating and storing inter-channel bias correction values for different temperature conditions. During operation, the system simply looks up the appropriate correction values based on measured temperature, avoiding complex real-time calculations while maintaining high positioning accuracy.
Solution Approach 2:
The patent introduces temperature as an intermediary parameter that mediates between the physical conditions affecting the receiver and the signal processing calculations. By using temperature as the intermediary, the system can accurately model and correct inter-channel biases without requiring complex direct measurements of each bias component.
3Speed
If fixed bias corrections are used to reduce computational load, then processing speed increases, but accuracy decreases due to temperature variations
Solution Approach 1:
The patent applies dynamics by transitioning from static, fixed bias corrections to dynamic, temperature-dependent bias corrections. The system continuously adapts the bias values based on real-time temperature measurements, ensuring both rapid processing (through efficient lookup tables) and high accuracy (through temperature-compensated corrections).
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Dynamic inter-channel bias calibration of a navigational receiver is provided. A reference signal is propagated through front end circuitry of the receiver. A delay caused by the propagation of the reference signal through the front end circuitry is measured. The inter-channel bias of the navigational receiver is reduced using the measured delay associated with the front end circuitry of the receiver.