Inductor based switching mixer circuit

Patent metadata

Field	Value
Publication number	US-9407304-B1
Application number	US-201514693440-A
Country	US
Kind code	B1
Filing date	Apr 22, 2015
Priority date	Apr 22, 2015
Publication date	Aug 2, 2016
Grant date	Aug 2, 2016

Abstract

A switching mixer that includes an input configured to receive a radio frequency (RF) signal, a set of inductors, and a set switches in a one-to-one relationship with the set of inductors. The set of switches are configured to alternate turning off in a quadrature sequence of a switching cycle. When a respective switch of the set of switches is turned off: the respective switch connects the input to a respective inductor of the set of inductors to convert the RF signal to a baseband current; and each remaining inductor of the set of inductors is configured to maintain current therein.

First claim

What is claimed is:

1. A switching mixer, comprising:
an input configured to receive a radio frequency (RF) signal;
a set of inductors; and,
a set switches in a one-to-one relationship with the set of inductors, the set of switches configured to alternate turning off in a quadrature sequence of a switching cycle,
wherein when a respective switch of the set of switches is turned off:
the respective switch connects the input to a respective inductor of the set of inductors to convert the RF signal to a baseband current; and
each remaining inductor of the set of inductors is configured to maintain current therein.

2. The switching mixer of claim 1 , wherein when the respective switch of the set of switches is turned on:
the respective switch shorts out the respective inductor, to maintain the current in the respective inductor.

3. The switching mixer of claim 1 , wherein each respective inductor of the set of inductors is connected in series and each respective switch is connected in parallel with the respective inductor in the set of inductors.

4. The switching mixer of claim 3 , further comprising:
a set of transimpedance amplifiers in a one-to-one relationship with the set of inductors, each transimpedance amplifier in the set of transimpedance amplifiers being configured to convert the baseband current to a baseband voltage.

5. The switching mixer of claim 1 , wherein each respective inductor in the set of inductors is connected in parallel with the input.

6. The switching mixer of claim 5 , further comprising:
a second set of switches configured to alternate turning on in the quadrature sequence of the switching cycle; and,
a set of transimpedance amplifiers in a one-to-one relationship with the set of inductors, each transimpedance amplifier in the set of transimpedance amplifiers being configured to convert the baseband current to a baseband voltage.

7. The switching mixer of claim 6 , wherein when a respective switch of the second set of switches is turned off:
the respective switch isolates the respective inductor, the respective switch and the respective transimpedance amplifier from the input.

8. The switching mixer of claim 1 , further comprising:
a gate driver circuit configured to receive a clock signal from a local oscillator and generate the quadrature sequence of the switching cycle from the clock signal.

9. The switching mixer of claim 1 , further comprising:
a capacitor switching mixer coupled to the input and configured to provide a low-impedance path to ground for RF signals outside a tuned frequency of the switching mixer.

10. A switching mixer, comprising:
an input configured to receive a radio frequency (RF) signal;
a first switch configured to receive a control signal having a switching cycle and to turn off to connect the input to a first inductor to generate a first baseband current from the RF signal and turn on to maintain the first baseband current in the first inductor based on the switching cycle;
a second switch configured to receive the control signal and to turn off to connect the input to a second inductor to generate a second baseband current from the RF signal and turn on to maintain the second baseband current in the second inductor based on the switching cycle;
a third switch configured to receive the control signal and to turn off to connect the input to a third inductor to generate a third baseband current from the RF signal and turn on to maintain the third baseband current in the third inductor based on the switching cycle; and
a fourth switch configured to receive the control signal and to turn off to connect the input to a fourth inductor to generate a fourth baseband current from the RF signal and turn on to maintain the fourth baseband current in the fourth inductor based on the switching cycle.

11. The switching mixer of claim 10 , wherein the switching cycle comprises four non-overlapping portions.

12. The switching mixer of claim 11 , wherein
the first switch is configured to turn off during a first portion of the four non-overlapping portions to connect the input to the first inductor to generate the first baseband current from the RF signal and turn on during a second portion of the four non-overlapping portions, during a third portion of the four non-overlapping portions, and during a fourth portion of the four non-overlapping portions to maintain the first baseband current in the first inductor;
the second switch is configured to turn off during the second portion of the four non-overlapping portions to connect the input to the second inductor to generate the second baseband current from the RF signal and turn on during the first portion of the four non-overlapping portions, during the third portion of the four non-overlapping portions, and during the fourth portion of the four non-overlapping portions to maintain the second baseband current in the second inductor;
the third switch is configured to turn off during the third portion of the four non-overlapping portions to connect the input to the third inductor to generate the third baseband current from the RF signal and turn on during the first portion of the four non-overlapping portions, during the second portion of the four non-overlapping portions, and during the fourth portions of the four non-overlapping portions to maintain the third baseband current in the third inductor; and,
the fourth switch is configured to turn off during the fourth portion of the four non-overlapping portions to connect the input to the fourth inductor to generate the fourth baseband current from the RF signal and turn on during the first portion of the four non-overlapping portions, during the second portion of the four non-overlapping portions, and during the third portion of the four non-overlapping portions to maintain the fourth baseband current in the fourth inductor.

13. The switching mixer of claim 10 , further comprising:
a first transimpedance amplifier configured to receive the first baseband current and to convert the first baseband current to a positive in-phase baseband voltage;
a second transimpedance amplifier configured to receive the second baseband current and to convert the second baseband current to a positive quadrature phase baseband voltage;
a third transimpedance amplifier configured to receive the third baseband current and to convert the first baseband current to a negative in-phase baseband voltage; and,
a fourth transimpedance amplifier configured to receive the fourth baseband current and to convert the fourth baseband current to a negative quadrature phase baseband voltage.

14. The switching mixer of claim 10 , wherein
the first inductor, the second inductor, the third inductor, and the fourth inductor are connected in series with the input;
the first switch is connected in parallel with the first inductor;
the second switch is connected in parallel with the second inductor;
the third switch is connected in parallel with the third inductor; and
the fourth switch is connected in parallel with the fourth inductor.

15. The switching mixer of claim 10 , wherein
the first inductor, the second inductor, the third inductor, and the fourth inductor are connected in parallel to the input;
the first switch is connected in between the input and the first inductor;
the second switch is connected in between the input and the second inductor;
the third switch is connected in between with the third inductor; and
the fourth switch is connected in between the input and the fourth inductor.

16. The switching mixer of claim 15 , further comprising:

Assignees

• Blackberry Ltd

Inventors

• Pawliuk Peter Cornelius
• Lin Nan Sen

Classifications

• H04B1/123 Primary

  using adaptive balancing or compensation means (adaptive filter circuits and algorithms H03H) · CPC title

• H04B2001/1072

  by tuning the receiver frequency · CPC title

• H04B1/1027

  assessing signal quality or detecting noise/interference for the received signal · CPC title

• H03D7/1483

  comprising components for selecting a particular frequency component of the output · CPC title

• H03D7/1441 Primary

  using field-effect transistors (H03D7/145 takes precedence) · CPC title