Two-Point Modulation Gain Calibration Using VCO Frequency Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Two-point modulation transmitters face performance degradation due to gain mismatch between high-pass and low-pass channels, which is not adequately addressed by existing calibration methods that require additional circuits and increase power consumption and cost.
Innovation Solution
A signal transmitting method that determines a gain mismatch compensation coefficient based on the relationship between the output voltage of a high-pass channel and the output frequency of a VCO, allowing for gain matching and nonlinear compensation without additional circuits, thereby reducing power consumption and cost.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If gain mismatch calibration is performed using existing methods, then signal transmission quality can be improved, but additional circuits are required which increases power consumption and device complexity
Solution Approach 1:
The system uses existing functional blocks (VCO, high-pass channel, low-pass channel) to perform self-calibration by measuring the relationship between output voltage and output frequency, eliminating the need for external calibration circuits. The device calibrates itself using its own operational characteristics.
Solution Approach 2:
The patent changes the calibration approach from circuit-based to parameter-based calibration. By measuring the relationship between output voltage and output frequency parameters of existing components, the system determines gain mismatch compensation coefficients without adding physical calibration circuits.
2Reliability
If additional calibration circuits are added to correct gain mismatch, then signal transmission quality improves, but power consumption increases
Solution Approach 1:
The system performs self-calibration using existing operational blocks, eliminating the need for separate calibration circuits that would consume additional power. The VCO and channel components are already operating and generating signals, so the calibration process reuses these existing power-consuming elements rather than adding new ones.
Solution Approach 2:
Existing components serve multiple functions: the VCO generates frequency signals for modulation and simultaneously provides frequency information for calibration measurements. The high-pass and low-pass channels process signals and simultaneously serve as measurement paths for determining gain mismatch, reducing the need for dedicated calibration power consumption.
3Device complexity
If gain mismatch is not compensated, then device complexity remains low, but signal transmission quality deteriorates due to nonlinear effects
Solution Approach 1:
The system performs preliminary calibration by measuring the output voltage-output frequency relationship before actual signal transmission. The gain mismatch compensation coefficients are determined in advance and stored, so that during normal operation, only simple coefficient application is needed rather than complex real-time calibration.
Solution Approach 2:
The system uses feedback from the VCO's own output frequency measurements to adjust and compensate for gain mismatch. By continuously monitoring the relationship between input voltage and output frequency, the system can determine compensation coefficients that correct nonlinear effects in the signal transmission path.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach improves signal transmission quality by eliminating nonlinear effects and reducing the need for additional calibration circuits, resulting in lower power consumption and cost for the electronic device.
Implementation Method 1
a gain mismatch compensation coefficient being determined according to an output voltage of a high-pass channel of a transmitter of the electronic device and an output frequency of a voltage-controlled oscillator (VCO) of the transmitter
Data Source
AI summary
Embodiments of the present disclosure provide a signal transmitting method. According to the method, in a signal transmitting process, before entering a digital to analog converter (DAC), a first frequency modulated signal of a high-pass channel is first subjected to nonlinear compensation and gain mismatch compensation. In the process, a nonlinear compensation coefficient and a gain mismatch compensation coefficient are determined according to an output voltage of the high-pass channel and an output frequency of a voltage-controlled oscillator (VCO) during a calibration stage.