Controllable Oscillator Circuit for Constant-Amplitude Frequency Tuning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Analog oscillators with controllable frequencies face issues where small changes in reactive elements cause abrupt changes in oscillation signal magnitude, especially when controlled by digital signals with discrete changes.
Innovation Solution
The oscillator design includes controllable reactive circuitry within the amplifier circuitry, allowing for controlled reactance responsive to control signals, ensuring that the resistive components of the amplifier and resonant circuitry impedances remain equal, thereby maintaining a constant oscillation signal magnitude by adjusting capacitances in a specific ratio.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If the value of a reactive element is changed to control frequency, then the frequency is tuned, but the magnitude of the oscillation signal changes abruptly
Solution Approach 1:
The patent changes the reactive element value in a specific manner that compensates for the natural magnitude variation. By controlling the reactance change to maintain equality between resistive components of amplifier and resonant circuitry impedances, the oscillation magnitude remains constant while frequency is tuned.
Solution Approach 2:
The patent employs feedback mechanisms where the control circuitry monitors the oscillation signal and adjusts the reactive element accordingly. This feedback loop ensures that frequency changes do not result in magnitude variations, maintaining stable oscillation output throughout the tuning range.
2Extent of automation
If digital control signals with discrete changes are used, then frequency tuning is achieved, but abrupt changes in signal magnitude occur
Solution Approach 1:
The patent makes the reactive element dynamically adjustable with continuous or finely granular control capability. Even when controlled by digital signals, the reactive element can change its value in a manner that smoothly maintains oscillation magnitude, transforming the discrete digital control into a dynamically stable analog response.
Solution Approach 2:
The patent applies parameter changes to the reactive element in a controlled manner that compensates for discrete control signal steps. By adjusting the reactance to maintain impedance balance, the system converts discrete digital control into continuous magnitude stabilization.
Data Source
AI summary
An oscillator, including amplifier circuitry and resonant circuitry, for providing an oscillation signal with a controllable frequency while maintaining a substantially constant steady state magnitude. Controllable reactive circuitry, included as part of the amplifier circuitry, has a reactance which can be controlled such that the resistive components of the amplifier circuitry and resonant circuitry impedances remain substantially equal. When in the form of serially coupled, controllable capacitances, the controllable reactive circuitry is controlled such that a ratio of changes in the controllable capacitances is approximately equal to a negative ratio of the capacitance values.