US 9,270,008 B2 · Transmission line resonator, bandpass filter using transmission line resonator, multiplexer, balanced-to-unbalanced transformer, power divider, unbalanced-to-balanced transformer, frequency mixer, and balance-type filter

Abstract

A transmission line resonator includes a half-wavelength stepped-impedance resonator with two ends short-circuited to ground, and a capacitive element with one end connected to a center portion of the stepped-impedance resonator and the other end short-circuited to ground. The stepped-impedance resonator includes a first transmission line, a second transmission line, and a third transmission line. The second transmission line has a second line impedance and a second line length, with one end being connected to one end of the first transmission line and the other end being short-circuited to ground. The third transmission line has the second line impedance and the second line length, with one end being connected to the other end of the first transmission line and the other end being short-circuited to ground. The first line impedance is lowered in comparison with the second line impedance.

Claims22

Dependent claims

A transmission line resonator comprising:

a half-wavelength stepped-impedance resonator;
and
a capacitive element with one end connected to a center portion of the stepped-impedance resonator and the other end short-circuited to ground, and
wherein the stepped-impedance resonator further comprises:
a first transmission line having a first line impedance and a first line length;
a second transmission line having a second line impedance and a second line length, with one end being connected to one end of the first transmission line and the other end being short-circuited to ground;
and
a third transmission line having the second line impedance and the second line length, with one end being connected to the other end of the first transmission line and the other end being short-circuited to ground,
wherein the first line impedance is lowered in comparison with the second line impedance, and
wherein the capacitive element satisfies the following formulas:
B
=
2
·
(
R
Z
-
tan
⁢
⁢
θ
1
·
tan
⁢
⁢
θ
2
)
Z
1
·
(
tan
⁢
⁢
θ
2
+
R
Z
·
tan
⁢
⁢
θ
1
)
[
Formula
⁢
⁢
1
]
R
Z
=
Z
1
Z
2
[
Formula
⁢
⁢
2
]
where jB represents an admittance of the capacitive element, Z1 represents the first line impedance, 2θ1 represents the first line length, Z2 represents the second line impedance, and θ2 represents the second line length.

66 more elements

An unbalanced-to-balanced transformer comprising:

a first transmission line having a first line impedance and a first line length;
a second transmission line having a second line impedance and a second line length, with one end being connected to one end of the first transmission line and the other end being short-circuited to ground;
a third transmission line having the second line impedance and the second line length, with one end being connected to the other end of the first transmission line and the other end being short-circuited to ground;
a capacitive element, with one end being connected to a center portion of the first transmission line and the other end being short-circuited to ground;
an input terminal that is electric-field coupled to a vicinity of a center portion of the first transmission line;
a first phase adjusting unit and a second phase adjusting unit having virtually the same line length, which are disposed so as to be adjacent to each other with a predetermined clearance from each other, respectively in parallel with the second transmission line and the third transmission line;
a first output terminal that is magnetic-field coupled to one end of the first phase adjusting unit, which is located at a position farthest from a short-circuit grounding unit of the second transmission line;
and
a second output terminal that is magnetic-field coupled to one end of the second phase adjusting unit, which is located at a position closest to a short-circuit grounding unit of the third transmission line,
wherein the first transmission line, the second transmission line and the third transmission line are disposed in a loop shape, with the other end of each of the first phase adjusting unit and the second phase adjusting unit being short-circuited to ground.

7 more elements

A bandpass filter with a balanced input and an unbalanced output comprising:

one or more sets of transmission line resonators, each having a first transmission line having a first line impedance and a first line length;
a second transmission line having a second line impedance and a second line length, with one end being connected to one end of the first transmission line and the other end being short-circuited to ground;
a third transmission line having the second line impedance and the second line length, with one end being connected to the other end of the first transmission line and the other end being short-circuited to ground;
and
a capacitive element, with one end being connected to a center portion of the first transmission line and the other end being short-circuited to ground,
wherein each of the one or more sets of transmission line resonators has a structure in which the first transmission line, the second transmission line and the third transmission line are formed by disposing the respective first transmission lines of two transmission line resonators having the same resonance frequency, disposed in a loop shape, so as to be adjacent to each other virtually in parallel with each other with a predetermined clearance from each other, and the plural sets of the transmission line resonators are disposed so as to be adjacent to each other with a predetermined clearance from each other in parallel with each of the second transmission line or the third transmission line, and longitudinally connected to one another successively by magnetic-field coupling,
wherein first and second input terminals are respectively magnetic-field coupled to a vicinity of a short-circuit grounding unit between the second transmission line and the third transmission line of a top transmission line resonator,
wherein an output terminal is electric-field coupled to a center portion of the first transmission line of the last transmission line resonator having a second transmission line and a third transmission line that are disposed so as to be adjacent in parallel with each other with a predetermined clearance from each other, and
wherein the capacitive element satisfies the following formulas:
B
=
2
·
(
R
Z
-
tan
⁢
⁢
θ
1
·
tan
⁢
⁢
θ
2
)
Z
1
·
(
tan
⁢
⁢
θ
2
+
R
Z
·
tan
⁢
⁢
θ
1
)
[
Formula
⁢
⁢
1
]
R
Z
=
Z
1
Z
2
[
Formula
⁢
⁢
2
]
where jB represents an admittance of the capacitive element, Z1 represents the first line impedance, 2θ1 represents the first line length, Z2 represents the second line impedance, and θ2 represents the second line length.

65 more elements

A balance-type filter comprising:

one or more sets of transmission line resonators, each having a first transmission line having a first line impedance and a first line length;
a second transmission line having a second line impedance and a second line length, with one end being connected to one end of the first transmission line and the other end being short-circuited to ground;
a third transmission line having the second line impedance and the second line length, with one end being connected to the other end of the first transmission line and the other end being short-circuited to ground;
and a capacitive element, with one end being connected to a center portion of the first transmission line and the other end being short-circuited to ground,
wherein each set of the transmission line resonators is formed by disposing respective first transmission lines of two of the one or more sets of transmission line resonators having the same resonance frequency, with the first, second and third transmission lines being disposed in a loop shape, so as to be adjacent virtually in parallel with each other with a predetermined clearance from each other, and the one or more sets of the transmission line resonators are disposed so as to be adjacent to each other with a predetermined clearance from each other in parallel with each of the second transmission line or the third transmission line, and longitudinally connected to one another successively by magnetic-field coupling with each other, and
wherein first and second input terminals are respectively magnetic-field coupled to a vicinity of a short-circuit grounding unit between the second transmission line and the third transmission line of a top transmission line resonator of the one or more sets of transmission line resonators, and a first phase adjusting unit and a second phase adjusting unit having the virtually the same line length are disposed adjacent to each other with a predetermined clearance virtually in parallel with the second transmission line and the third transmission line of the last transmission line resonator of the one or more sets of transmission line resonators, and
wherein a first output terminal that is magnetic-field coupled to one of ends of the first phase adjusting unit located at a position farthest from the portion that is short-circuited to ground of the second transmission line and a second output terminal that is magnetic-field coupled to one of ends of the second phase adjusting unit located at a position closest to the portion that is short-circuited to ground of the third transmission line are prepared, with the other ends of the first phase adjusting unit and the second phase adjusting unit being short-circuited to ground.

4 more elements

Dependencies are inferred from the claim text.

Transmission line resonator, bandpass filter using transmission line resonator, multiplexer, balanced-to-unbalanced transformer, power divider, unbalanced-to-balanced transformer, frequency mixer, and balance-type filter

Life of this patent

Transmission line resonator, bandpass filter using transmission line resonator, multiplexer, balanced-to-unbalanced transformer, power divider, unbalanced-to-balanced transformer, frequency mixer, and balance-type filter

Life of this patent

Abstract

Claims22