Hybrid coupler
View Patent ↗A circuit for amplifying an input signal can comprise a plurality of couplers. A splitting coupler of the plurality of couplers can receive the input signal and a combining coupler of the plurality of couplers can provides an output signal. N number of amplifiers can be included in the circuit to amplify the input signal, wherein N is a non-binary integer greater than one. At least one of the plurality of couplers can comprise a hybrid coupler that has two ports terminated into substantially equal reactances.
1. A circuit for amplifying an input signal comprising:
a plurality of couplers, wherein a splitting coupler of the plurality of couplers receives the input signal and a combining coupler of the plurality of couplers provides an output signal; and
N number of amplifiers to amplify the input signal, wherein N is a non-binary integer greater than one;
wherein at least two of the plurality of couplers comprises a first hybrid coupler and a second hybrid coupler, each of the first and second hybrid couplers having two ports coupled to nodes with substantially equal reactances.
2. The circuit of claim 1 , wherein the hybrid coupler has.
3. The circuit of claim 1 , wherein the hybrid coupler has a thru port and a coupled port providing an open circuit.
4. The circuit of claim 1 , wherein N is equal to five and an isolated port of the second hybrid coupler is coupled to an amplifier of the N number of amplifiers.
5. The circuit of claim 4 , wherein the output signal has a delay of about 5 times a delay of a thru port of a given coupler of the plurality of couplers plus a phase shift of about 180 degrees relative to the input signal.
6. The circuit of claim 1 , wherein N is equal to three and the output signal has a delay of about 4 times a delay of a thru port of a given coupler of the plurality of couplers plus a phase shift of about 90 degrees relative to the input signal.
7. The circuit of claim 1 , wherein the circuit has a bandwidth of at least one octave.
8. The circuit of claim 1 , wherein each of the plurality of couplers provides a substantially equal nonlinear insertion phase.
9. The circuit of claim 8 , wherein:
V
thru
=
1
-
K
2
1
-
K
2
cos
(
(
B
)
(
L
)
)
+
j
sin
(
(
B
)
(
L
)
)
;
B
=
2
π
λ
;
and
λ
=
Vp
f
;
wherein:
V thru comprises an output voltage at a thru port of a given coupler of the plurality of couplers;
K comprises a coupling coefficient of the given coupler;
λ comprises the wavelength, in meters of the input signal;
f is the frequency, in hertz (Hz) of the input signal;
Vp is the propagation velocity of a medium containing the given coupler, in meters per second; and
L is the length of the given coupler, in meters.
10. The circuit of claim 9 , wherein
V
coupled
=
j
K
sin
(
(
B
)
(
L
)
)
1
-
K
2
cos
(
(
B
)
(
L
)
)
+
j
sin
(
(
B
)
(
L
)
)
;
wherein:
V coupled comprises an output voltage at a coupled port of the given coupler of the plurality of couplers.
11. The circuit of claim 1 , wherein the at least one hybrid coupler has a coupling factor of about −3 decibels (dB).
12. The circuit of claim 11 , wherein each of the splitting coupler and the combining coupler have a coupling factor greater than a coupling factor of the at least one hybrid coupler.
13. A system for amplifying an input signal comprising:
a signal source to provide the input signal;
a phase compensating amplifier system comprising:
three amplifiers configured to amplify the input signal; and
a plurality of couplers arranged and configured to compensate for a nonlinear insertion phase of the plurality of couplers, wherein at least one of the couplers comprises a hybrid coupler to provide a phase advance of the input signal; and
a load that receives an output signal from the phase compensating amplifier system;
wherein the output signal has a delay substantially equal to three times a delay of a thru port of a given coupler plus a phase shift of about 90 degrees relative to the input signal.
14. The system of claim 13 , wherein the load comprises a radio frequency (RF) antenna.
15. The system of claim 13 , wherein the at least one hybrid coupler has two ports terminated into substantially equal reactances.
16. A circuit for amplifying an input signal comprising:
a plurality of couplers, wherein a splitting coupler of the plurality of couplers receives the input signal and a combining coupler of the plurality of couplers provides an output signal; and
N number of amplifiers to amplify the input signal, wherein N is a non-binary integer greater than one;
wherein at least one of the plurality of couplers comprises a hybrid coupler that has two ports terminated into substantially equal reactances, such that the hybrid coupler has one of a thru port and a coupled port providing an open circuit and a thru port and a coupled port terminated into a short.