Systems and methods for extending frequency response of resonant transducers

Patent metadata

Field	Value
Publication number	US-11255718-B2
Application number	US-202015929574-A
Country	US
Kind code	B2
Filing date	May 11, 2020
Priority date	Jun 16, 2014
Publication date	Feb 22, 2022
Grant date	Feb 22, 2022

Abstract

Certain implementations of the disclosed technology may include systems and methods for extending a frequency response of a transducer. A method is provided that can include receiving a measurement signal from a transducer, wherein the measurement signal includes distortion due to a resonant frequency of the transducer. The method includes applying a complementary filter to the measurement signal to produce a compensated signal, wherein applying the complementary filter reduces the distortion to less than about +/−1 dB for frequencies ranging from about zero to about 60% or greater of the resonant frequency. The method further includes outputting the compensated signal.

First claim

What is claimed is:

1. A method comprising:
receiving, responsive to an applied pressure, an electrical measurement signal from a sensor having a protective screen, wherein the measurement signal includes a distortion due to the protective screen;
applying, to the measurement signal, a complementary compensation filter circuit adapted to compensate for the distortion in the measurement signal, wherein applying the complementary compensation filter circuit reduces the distortion to less than 1 dB for frequencies ranging from zero up to 60% of a resonant frequency and less than 2 dB for frequencies ranging from over 60% to 90% of the resonant frequency; and
outputting the compensated signal, wherein the compensated signal reduces a resonance associated with the sensor.

2. The method of claim 1 , wherein applying the complementary compensation filter circuit to the measurement signal comprises applying a second order transfer function to the measurement signal to produce a compensated frequency response signal filter having a frequency response based on an inverse frequency response of the sensor, wherein the second order transfer function is implemented by a double integrator with feedback.

3. The method of claim 1 , further comprising;
determining the resonant frequency associated with a frequency response of the sensor; and
determining a quality factor complementary to the frequency response of the sensor.

4. The method of claim 3 , further comprising:
determining a compensated frequency response of the sensor based on one or more of the determined resonant frequency and the determined quality factor.

5. The method of claim 1 , wherein the complementary compensation filter circuit is an analog circuit.

6. The method of claim 1 , wherein the complementary compensation filter circuit includes a Helmholtz frequency response, T c (f), represented by the equation:

T
C

⁡

(
f
)

=

-

f
2

+

i
⁢

⁢
f
⁢

⁢

f
n

Q

+

f
n
2

-

f
2

+

i
⁢

⁢
f
⁢

⁢

f
n

+

f
n
2

wherein f is a frequency variable, f n is the resonant frequency of the sensor, and Q is a quality factor associated with the sensor frequency response.

7. The method of claim 1 , wherein the complementary compensation filter circuit includes a seismic mass frequency response, T c (f), represented by the equation:

T
C

⁡

(
f
)

=

-

f
2

+

i
⁢

⁢
f
⁢

⁢

f
n

Q

+

f
n
2

f
n
2

wherein f is the frequency variable, f n is the resonant frequency of the sensor, and Q is a quality factor associated with the sensor frequency response.

8. The method of claim 1 , wherein the sensor comprises a diaphragm having a resonant frequency modeled by

f
=

3
⁢
6

2
⁢
π

⁢

Et
2

12
⁢
ρ
⁢

a
4

⁡

(

1
-

v
2

)

and wherein the diaphragm is flat and square having a length a and thickness t, and where E is Young's modulus, ν is Poisson's ratio of the diaphragm material, and ρ is the applied pressure measured in Pascals.

9. The method of claim 1 , wherein the distortion is further due to a resonance of the sensor.

10. A filter comprising:
a measurement input terminal adapted to receive an electrical measurement signal from a sensor having a protective screen responsive to a pressure applied to a diaphragm of the sensor, wherein the measurement signal includes a distortion due to the protective screen associated wit

Assignees

• Kulite Semiconductor Products Inc

Inventors

• Vandeweert Joe
• Hurst Adam
• Carter Joseph
• Firth Douglas R
• Szary Alan R

Classifications

• G01H11/08 Primary

  using piezoelectric devices · CPC title

• G01H13/00 Primary

  Measuring resonant frequency · CPC title

• G01L9/065

  with temperature compensating means (non electric temperature compensating means G01L19/04) · CPC title

• G01L9/0047

  Diaphragm with non uniform thickness, e.g. with grooves, bosses or continuously varying thickness · CPC title