Traveling wave mixer

Patent metadata

Field	Value
Publication number	US-11742801-B2
Application number	US-202217878244-A
Country	US
Kind code	B2
Filing date	Aug 1, 2022
Priority date	Oct 29, 2021
Publication date	Aug 29, 2023
Grant date	Aug 29, 2023

Abstract

A travelling wave mixer (TWM) is provided that includes an input artificial transmission line configured to transmit an input signal, an output artificial transmission line configured to transmit an output signal, a local oscillator (LO) artificial transmission line configured to transmit an LO signal, and a plurality of mixer stages connected in parallel between the output artificial transmission and the input artificial transmission line. Each of the mixer stages includes an input amplifier, a mixer and an output amplifier connected in series between the input artificial transmission line and the output artificial transmission line, where an input of the mixer receives an output of the input amplifier, and an output of the mixer is applied to an input of the output amplifier. Further, each of the mixer stages includes a phase-adjustable LO amplifier circuit connected between the LO artificial transmission line and an LO input of the mixer, where the phase-adjustable LO amplifier is configured to adjust an LO signal phase applied to the LO input of each mixer to null out a phase error in each mixer stage independently.

First claim

What is claimed is:

1. A travelling wave mixer (TWM), comprising:
an input artificial transmission line configured to transmit an input signal;
an output artificial transmission line configured to transmit an output signal;
a local oscillator (LO) artificial transmission line configured to transmit an LO signal; and
a plurality of mixer stages connected in parallel between the output artificial transmission and the input artificial transmission line;
wherein each of the mixer stages comprises an input amplifier, a mixer and an output amplifier connected in series between the input artificial transmission line and the output artificial transmission line, where an input of the mixer receives an output of the input amplifier, and an output of the mixer is applied to an input of the output amplifier, and
wherein each of the mixer stages further comprises a phase-adjustable LO amplifier circuit connected between the LO artificial transmission line and an LO input of the mixer, the phase-adjustable LO amplifier configured to adjust an LO signal phase applied to the LO input of each mixer to null out a phase error in each mixer stage independently.

2. The TWM of claim 1 , wherein the phase error in each mixer stage nulled out by the phase-adjustable LO amplifier is a phase error in the signal path from the LO artificial transmission line to the output of the mixer in each stage.

3. The TWM of claim 1 , wherein the phase error in each mixer stage nulled out by the phase-adjustable LO amplifier is a phase error of an upper side band signal or a lower side band signal at the output of the mixer in each stage.

4. The TWM of claim 1 , wherein the input signal comprises a range of frequencies, and the phase error in each mixer stage nulled out by the phase-adjustable LO amplifier is one half a difference between a maximum phase error and a minimum phase error in an upper side band signal or a lower side band signal at the output of the mixer in each stage.

5. The TWM of claim 1 , wherein the phase-adjustable LO amplifier is configured to adjust a duty cycle of the LO signal applied to the LO input of the mixer.

6. The TWM of claim 5 , where the duty cycle is adjusted to 50%.

7. The TWM of claim 1 , wherein the phase-adjustable LO amplifier functions as an isolation element which inhibits input and output signals of the mixer of each mixer stage from coupling back to the LO artificial transmission line.

8. The TWM of claim 7 , wherein the phase-adjustable LO amplifier functions to minimize a capacitance on the LO artificial transmission line and maximize a voltage swing delivered to the mixer of each mixer stage.

9. The TWM of claim 1 , wherein the input amplifier of each mixer stage is a transconductance amplifier.

10. The TWM of claim 9 , wherein the output amplifier of each mixer stage is a cascode amplifier.

11. The TWM of claim 1 , wherein the input, output and LO artificial transmission lines are implemented with inductors.

12. The TWM of claim 1 , wherein the input, output and LO artificial transmission lines are implemented with high-impedance transmission line sections.

13. The TWM of claim 1 , further comprising at least one feed forward mixer correction stage connected in parallel between the input transmission line and the output transmission line.

14. The TWM of claim 12 , wherein each feed forward mixer correction stage comprises an amplifier and a mixer connected in series between the input transmission line and the output transmission line, where an input of the mixer receives an output of the input amplifier, and an output of the mixer is applied to an input of the output amplifier, and
wherein each feed forward mixer correction stage further comprises a phase-adjustable LO amplifier circuit connected between the LO transmission line and an LO input of the mixer, the phase-adjustable LO amplifier configured to adjust an LO signal phase applied to the LO input of each mixer to null out a phase error in each feed forward mixer correction stage independently.

15. The TWM of claim 1 , further comprising at least analog impairment correction stage connected in parallel between the input transmission line and the output transmission line.

16. The TWM of claim 12 , wherein each analog impairment correction stage comprises an input amplifier, a mixer and an output amplifier connected in series between the input transmission line and the output transmission line, where an input of the mixer receives an output of the amplifier, and an output of the mixer is applied to an input of the output amplifier, and
wherein each feed forward mixer correction stage further comprises a phase-adjustable LO amplifier circuit connected between the LO transmission line and an LO input of the mixer, the phase-adjustable LO amplifier configured to adjust an LO signal phase applied to the LO input of each mixer to null out a phase error in each feed forward mixer correction stage independently.

17. A travelling wave IQ-mixer (TWM-IQ), comprising:
first and second input artificial transmission lines each configured to transmit an input signal;
an output artificial transmission line configured to transmit an output signal;
first and second local oscillator (LO) artificial transmission line each configured to transmit an LO signal;
a first plurality of mixer stages connected in parallel between the artificial output transmission line and the first input artificial transmission line; and
a second plurality of mixer stages connected in parallel between the artificial output transmission line and the second input artificial transmission line;
wherein each of the first mixer stages comprises an input amplifier, a mixer and an output amplifier connected in series between the first input artificial transmission line and the output artificial transmission line, where an input of the mixer receives an output of the amplifier, and an output of the mixer is applied to an input of the output amplifier,
wherein each of the first mixer stages further comprises a phase-adjustable LO amplifier circuit connected between the first LO artificial transmission line and an LO input of the mixer, the phase-adjustable LO amplifier configured to adjust an LO signal phase applied to the LO input of each mixer to null out a phase error in each first mixer stage independently,
wherein each of the second mixer stages comprises an input amplifier, a mixer and an output amplifier connected in series between the second input artificial transmission line and the output artificial transmission line, where an input of the mixer receives an output of the input amplifier, and an output of the mixer is applied to an input of the output amplifier, and
wherein each of the second mixer stages further comprises a phase-adjustable LO amplifier circuit connected between the second LO artificial transmission line and an LO input of the mixer, the phase-adjustable LO amplifier configured to adjust an LO signal phase applied to the LO input of each mixer to null out a phase error in each second mixer stage independently.

18. The TWM of claim 17 , wherein the phase error in each mixer stage nulled out by the phase-adjustable LO amplifier is a phase error in the signal path from the LO artificial transmission line to the output of the mixer in each stage.

19. The TWM of claim 17 , wherein the phase error in each mixer stage nulled out by the phase-adjustable LO amplifier is a phase error of an upper side band signal or a lower side band signal at the output of the mixer in each stage.

Assignees

• Keysight Technologies Inc

Inventors

• Pasha Rizwan

Classifications

• H03D7/12 Primary

  by means of semiconductor devices having more than two electrodes (H03D7/14 - H03D7/22 take precedence) · CPC title

• H03D7/14

  Balanced arrangements · CPC title

• H03F3/58

  using travelling-wave tubes · CPC title

• H03F3/45475 Primary

  using IC blocks as the active amplifying circuit · CPC title

• H03D7/1458

  Double balanced arrangements, i.e. where both input signals are differential · CPC title