Phase shifter

Patent metadata

Field	Value
Publication number	US-10418972-B2
Application number	US-201815974035-A
Country	US
Kind code	B2
Filing date	May 8, 2018
Priority date	Jul 6, 2017
Publication date	Sep 17, 2019
Grant date	Sep 17, 2019

Abstract

The disclosure relates to a phase shifter having a first mode of operation and a second mode of operation, the phase shifter comprising a mixer stage configured to mix an oscillator signal with an analog signal to provide a phase shifted signal, switching circuitry and a controller arranged to provide the analog signal to the mixer stage as a voltage in the first mode of operation and as a current in the second mode of operation.

First claim

The invention claimed is:

1. A phase shifter comprising:
a mixer stage configured to mix an oscillator signal with an analogue signal to provide a phase shifted signal,
switching circuitry and a controller configured to provide the analogue signal to the mixer stage as a voltage in a first mode of operation and as a current in a second mode of operation;
wherein the mixer stage comprises a mixer and a transconductance stage, wherein the controller is configured to control the switching circuity to:
provide the analogue signal to the transconductance stage and connect the transconductance stage to the mixer in the first mode of operation; and
provide the analogue signal to the mixer in the second mode of operation;
control the switching circuity to isolate the transconductance stage from the mixer or analogue signal in the second mode of operation.

2. The phase shifter of claim 1 , wherein the phase shifter comprises an in-phase mixer and a quadrature mixer for mixing an oscillator signal with the respective in-phase and quadrature analogue signals to provide phase shifted signals in accordance with the desired in-phase and quadrature-phase shifts.

3. A transmitter module comprising: a phase shifter comprising: a mixer stage configured to mix an oscillator signal with an analogue signal to provide a phase shifted signal, switching circuitry and a controller configured to provide the analogue signal to the mixer stage as a voltage in a first mode of operation and as a current in a second mode of operation, and a digital-to-analogue converter configured to receive a control signal indicative of a desired phase shift and to provide the analogue signal in accordance with the desired phase shift.

4. The transmitter module of claim 3 further comprising a selectable load, wherein the switching circuitry and the controller are configured to:
engage the selectable load with an output of the digital-to-analogue converter in the first mode of operation to provide a voltage, and
isolate the selectable load from the output of the digital-to-analogue converter in the second mode of operation.

5. The transmitter module of claim 3 further comprising a low pass filter, wherein the switching circuitry and the controller are configured to:
engage the low pass filter with an output of the digital-to-analogue converter in the first mode of operation, and
isolate the low pass filter from the output of the digital-to-analogue converter in the second mode of operation.

6. The transmitter module of claim 3 , comprising:
a direct digital synthesiser configured to provide the control signal to the digital-to-analogue converter; and
a sigma delta modulator,
wherein the switching circuity and controller are further configured to:
engage the sigma-delta modulator between the direct digital synthesiser and the digital-to-analogue converter in the first mode of operation; and
provide the control signal from the direct digital synthesiser to the digital-to-analogue converter in the second mode of operation.

7. The transmitter module of claim 6 , wherein the switching circuity and controller are further configured to isolate the sigma-delta modulator from the direct digital synthesiser or the digital-to-analogue converter in the second mode of operation.

8. The transmitter module of claim 3 , wherein the digital to analogue converter comprises:
an in-phase digital-to-analogue converter configured to receive a control signal indicative of a desired in-phase shift and to provide an in-phase analogue signal in accordance with the desired in-phase shift; and
a quadrature-phase digital-to-analogue converter configured to receive a control signal indicative of a desired quadrature-phase shift and to provide a quadrature-phase analogue signal in accordance with the desired quadrature-phase shift.

9. The transmitter module of claim 3 , wherein the digital-to-analogue converter has 7 bits.

10. A transceiver having a normal mode of transmitter operation and a self-test mode of operation, comprising:
a phase shifter comprising:
a mixer stage configured to mix an oscillator signal with an analogue signal to provide a phase shifted signal,
switching circuitry and a controller configured to provide the analogue signal to the mixer stage as a voltage in a first mode of operation and as a current in a second mode of operation;

a controller configured to drive the phase shifter:
in a current mode during the normal mode of transmitter operation; and
in a voltage mode during the self-test mode of operation.

11. The transceiver of claim 10 comprising only a single in-phase phase shifter and a single quadrature phase shifter.

12. The transceiver of claim 10 , wherein the transceiver is a RADAR transceiver.

13. The transmitter module of claim 4 further comprising a low pass filter, wherein the switching circuitry and the controller are configured to:
engage the low pass filter with an output of the digital-to-analogue converter in the first mode of operation, and
isolate the low pass filter from the output of the digital-to-analogue converter in the second mode of operation.

14. The transmitter module of claim 4 , comprising:
a direct digital synthesiser configured to provide the control signal to the digital-to-analogue converter; and
a sigma delta modulator, wherein the switching circuity and controller are further configured to:
engage the sigma-delta modulator between the direct digital synthesiser and the digital-to-analogue converter in the first mode of operation; and
provide the control signal from the direct digital synthesiser to the digital-to-analogue converter in the second mode of operation.

15. A transceiver having a normal mode of transmitter operation and a self-test mode of operation, comprising:
the transmitter module of claim 3 ; and
a controller configured to drive the phase shifter:
in a current mode during the normal mode of transmitter operation; and
in a voltage mode during the self-test mode of operation.

16. The transmitter module of claim 3 , wherein the mixer stage comprises a mixer and a transconductance stage, wherein the controller is configured to control the switching circuity to:
provide the analogue signal to the transconductance stage and connect the transconductance stage to the mixer in the first mode of operation; and
provide the analogue signal to the mixer in the second mode of operation.

17. The transmitter module of claim 16 , wherein the controller is configured to control the switching circuity to isolate the transconductance stage from the mixer or analogue signal in the second mode of operation.

18. The transmitter module of claim 3 , wherein the phase shifter comprises an in-phase mixer and a quadrature mixer for mixing an oscillator signal with the respective in-phase and quadrature analogue signals to provide phase shifted signals in accordance with the desired in-phase and quadrature-phase shifts.

19. The transmitter module of claim 4 , wherein the mixer stage comprises a mixer and a transconductance stage, wherein the controller is configured to control the switching circuity to:
provide the analogue signal to the transconductance stage and connect the transconductance stage to the mixer in the first mode of operation; and
provide the analogue signal to the mixer in the second mode of operation.

20. The transmitter module of claim 19 , wherein the controller is configured to control the switching circuity to isolate the transconductance stage from the mixer

Assignees

• Nxp Bv

Inventors

• Thuries Stephane
• Pavao Moreira Cristian
• Montoriol Gilles

Classifications

• G01S13/34

  using transmission of continuous, frequency-modulated waves while heterodyning the received signal, or a signal derived therefrom, with a locally-generated signal related to the contemporaneously transmitted signal · CPC title

• G01S7/4056

  specially adapted to FMCW · CPC title

• H04L27/362

  Modulation using more than one carrier, e.g. with quadrature carriers, separately amplitude modulated (H04L27/366 takes precedence) · CPC title

• H03M1/66

  Digital/analogue converters ({H03M1/001 – } H03M1/10 take precedence) · CPC title

• H03H11/16 Primary

  Networks for phase shifting · CPC title