Nanoresonator Resonance Measurement Circuit With Stored Phase Calibration

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing resonance frequency measurement circuits using nano-resonators face challenges in guaranteeing forced oscillation at the resonance frequency due to technological dispersions, while consuming more energy and being bulkier, especially when dealing with a large network of NEMS resonators.

Innovation Solution

An electronic circuit with a phase-locked loop and a controllable phase shifter, where a second feedback loop reduces phase shift to zero, and a self-oscillation loop is activated during operation, using stored calibration phase commands to maintain resonance frequency measurement with reduced energy consumption and compact design.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a phase-locked loop circuit is used to guarantee forced oscillation at resonance frequency, then measurement reliability is improved, but energy consumption increases and device size increases

Engineering Contradiction:
Improvemeasurement reliabilityVSAvoidenergy consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent applies preliminary action by performing calibration measurements before actual operation. During calibration, the phase-locked loop is activated to measure and store the phase shift introduced by the resonator and amplifier at resonance frequency. This pre-stored calibration data is then used during normal operation to compensate for phase shifts without requiring continuous activation of the full phase-locked loop circuit, thereby reducing energy consumption while maintaining measurement reliability.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent implements partial action by using only the essential components of the phase-locked loop during normal operation. Instead of maintaining the complete phase-locked loop circuit active, the system uses a simplified approach where only the phase shift compensation based on pre-stored calibration data is applied. This partial usage maintains the necessary measurement reliability while significantly reducing energy consumption and device complexity.

Inventive Principle:
Principle #16Partial or excessive action

2Reliability

If a phase-locked loop circuit is used to guarantee forced oscillation at resonance frequency, then measurement reliability is improved, but device complexity increases

Engineering Contradiction:
Improvemeasurement reliabilityVSAvoidcircuit complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies preliminary action by performing calibration measurements before actual operation. During calibration, the phase-locked loop is activated to measure and store the phase shift introduced by the resonator and amplifier at resonance frequency. This pre-stored calibration data is then used during normal operation to compensate for phase shifts without requiring continuous activation of the full phase-locked loop circuit, thereby reducing energy consumption while maintaining measurement reliability.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent implements partial action by using only the essential components of the phase-locked loop during normal operation. Instead of maintaining the complete phase-locked loop circuit active, the system uses a simplified approach where only the phase shift compensation based on pre-stored calibration data is applied. This partial usage maintains the necessary measurement reliability while significantly reducing energy consumption and device complexity.

Inventive Principle:
Principle #16Partial or excessive action

3Productivity

If multiple nano-resonators are measured in parallel, then productivity is improved, but energy consumption increases and device size increases

Engineering Contradiction:
Improvemeasurement throughputVSAvoidenergy consumption
Core Design Contradiction:
ProductivityVSUse of energy by moving object

Solution Approach 1:

The patent applies preliminary action by performing calibration measurements before actual operation. During calibration, the phase-locked loop is activated to measure and store the phase shift introduced by the resonator and amplifier at resonance frequency. This pre-stored calibration data is then used during normal operation to compensate for phase shifts without requiring continuous activation of the full phase-locked loop circuit, thereby reducing energy consumption while maintaining measurement reliability.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent implements partial action by using only the essential components of the phase-locked loop during normal operation. Instead of maintaining the complete phase-locked loop circuit active, the system uses a simplified approach where only the phase shift compensation based on pre-stored calibration data is applied. This partial usage maintains the necessary measurement reliability while significantly reducing energy consumption and device complexity.

Inventive Principle:
Principle #16Partial or excessive action

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

The circuit ensures accurate resonance frequency measurement across multiple resonators with reduced energy consumption and compact design, suitable for large networks of nano-resonators, by leveraging stored calibration phase commands to maintain self-oscillation at the resonance frequency.

Implementation Method 1

the signal to be measured is the resonance frequency of the nano-resonator, this in fact directly depending on the mass of material deposited on the resonator

Methodology Applied
Scientific EffectMechanical resonance: Resonance

Implementation Method 2

a phase-locked loop comprising the resonator, a controlled frequency oscillator and a first comparator phase, this loop slaving the frequency of a controlled oscillator to the resonant frequency of the resonator

Methodology Applied
Scientific EffectPhase-locked loop feedback control: Feedback

Implementation Method 3

a second feedback loop comprising a controllable phase shifter, a second phase comparator receiving the output of the controlled oscillator and the output of the controllable phase shifter, the second phase comparator supplying a phase shifter control signal acting in a direction tending to reduce to zero the phase shift between its inputs

Methodology Applied
Scientific EffectPhase shifting:

Data Source

PatentEP2700919B1Circuit for measuring the resonance frequency of nanoresonators
Publication Date: 2015.01.14 COMMISSARIAT A LENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES
  • EP2700919B1 patent drawingFigure 1~2
  • EP2700919B1 patent drawingFigure 3
  • EP2700919B1 patent drawingFigure 4

AI summary

The invention relates to nanoresonator oscillators or NEMS oscillators (from the English "nanoelectromechanical systems"). A resonator frequency measurement circuit (NMS) is provided, comprising a first phase-locked feedback loop (B1) that locks the frequency of a variable frequency drive (VCO) to the resonator's resonant frequency. This first loop includes a first phase comparator (CMPH1). Furthermore, a second feedback loop (B2) is provided that searches for and stores (MEM) the loop phase shift introduced by the resonator and its amplification circuit when they are locked to resonance by the first loop. The first and second loops operate during a calibration phase. A third self-oscillation loop (B3) is established during an operating phase.It directly connects the output of the controllable phase shifter to the input of the resonator. The phase shifter receives the phase shift command stored by the second loop.