Sensing circuit

Patent metadata

Field	Value
Publication number	US-12395141-B2
Application number	US-202318196202-A
Country	US
Kind code	B2
Filing date	May 11, 2023
Priority date	Nov 17, 2020
Publication date	Aug 19, 2025
Grant date	Aug 19, 2025

Abstract

Disclosed are example embodiments of a circuit comprising a first inductor-capacitor (LC) loop, a second LC loop having at least one of a series connection or parallel connection to the first LC loop, and a gyrator coupled between the first LC loop and the second LC loop. In an example, the first LC and the second LC loop each include an inductive element (L) and a capacitive (C) element coupled to each other in series. In another example, the first LC and the second LC loop each include an inductive element (L) and a capacitive (C) element coupled to each other in parallel.

First claim

The invention claimed is:

1. A circuit comprising:
a first inductor-capacitor (LC) loop;
a second LC loop having at least one of a series connection or parallel connection to the first LC loop; and
a gyrator coupled between the first LC loop and the second LC loop,
wherein the first LC loop and the second LC loop each include an inductive element (L) and a capacitive (C) element coupled to each other in series.

2. The circuit of claim 1 , wherein a circuit state before a measurement is a work state, wherein a quantity, w, in relations

Δ
⁢

(

C
1

)

=

w
+
x

with

(

ω

0
⁢
1

ω

0
⁢
2

-
1

)

⁢
w

<
0

,

❘
"\[LeftBracketingBar]"

x

❘
"\[RightBracketingBar]"

≤

❘
"\[LeftBracketingBar]"

w

❘
"\[RightBracketingBar]"

2

,

❘
"\[LeftBracketingBar]"

w

❘
"\[RightBracketingBar]"

≪
1

under assumption −(ω 01 /ω 02 −1) w>0 is referred to as a work point, wherein w=0 corresponds to an exceptional point of degeneracy (EPD) point, and the parameter w is selected to ensure that −(ω 01 /ω 02 −1) Δ(C 1 )>0 thereby enforcing circuit stability near the exceptional point of degeneracy,
where C 1 is a capacitance, ω 01 is an angular resonance frequency, ω 02 is an angular resonance frequency,
wherein the work state is defined as a steady-state operating condition of the circuit immediately prior to the measurement event,
wherein the circuit state refers to a configuration of the circuit defined by the values of capacitive and inductive elements therein and an operating frequency thereof.

3. The circuit of claim 1 , wherein a circuit parameter, X, corresponding to a sensor element, is greater than zero.

4. The circuit of claim 1 , wherein an exceptional point of degeneracy (EPD) point is chosen so that

ω
01

=

1

L
1

⁢

C
1

>

ω

02

=

1

L
2

⁢

C
2

.

where L 1 is an inductance of the first LC loop, L 2 is an inductance of the second LC loop, C 1 is a capacitance of the first LC loop, C 2 is a capacitance of the second LC loop, R g is a resistance of the gyrator, ω 01 is an angular resonance frequency of the first LC loop, and ω 02 is an angular resonance frequency of the second LC loop.

5. The circuit of claim 2 , wherein the first LC loop, the second LC loop, and the gyrator are configured such that parameters of the circuit satisfy:
sgn (ω 01 2 )= sgn (ω 02 2 )=− sgn ( L 1 L 2 )=±1 and R g 2 =(|ω 01 |±|ω 02 1 ) 2 |L 1 L 2 |,

where L 1 is an inductance of the first LC loop, L 2 is an inductance of the second LC loop, C 1 is a capacitance of the first LC loop, C 2 is a capacitance of the second LC loop, Re is a resistance of the gyrator, ω 01 is an angular resonance frequency of the first LC loop, and ω 02 is an angular resonance frequency of the second LC loop.

6. The circuit of claim 5 , wherein the first LC loop comprises a first inductive element and a first capacitive element, of positive values, wherein a second LC loop comprises a second inductive element and a second capacitive element, of negative values, wherein the gyrator couples the first LC loop and the second LC loop.

7. The circuit of claim 5 , wherein the first LC loop comprises a first inductive element and a first capacitive element, one with a positive value while the other has a negative value, wherein the second LC loop comprises a second inductive element and a second capacitive element, one with a positive value while the other has a negative value, wherein the gyrator couples the first LC loop and the second LC loop.

8. The circuit of claim 2

Assignees

• Univ California

Inventors

• Figotin Alexander
• Capolino Filippo

Classifications

• H03H7/0115

  comprising only inductors and capacitors (H03H7/075, H03H7/09, H03H7/12, H03H7/13 take precedence) · CPC title

• H03H11/08

  using gyrators · CPC title

• H03H7/1775

  Parallel LC in shunt or branch path (H03H7/1791 takes precedence) · CPC title

• H03H7/175

  Series LC in series path (H03H7/1783 takes precedence) · CPC title

• H03H7/002 Primary

  Gyrators · CPC title