Frequency/phase synthesizer noise cancellation

Patent metadata

Field	Value
Publication number	US-2019028209-A1
Application number	US-201815893461-A
Country	US
Kind code	A1
Filing date	Feb 9, 2018
Priority date	Jul 20, 2017
Publication date	Jan 24, 2019
Grant date	—

Abstract

An open-loop feed-forward cross-correlator noise cancellation device includes a synthesizer to generate a synthesized output clock signal based on a reference clock signal. The open-loop feed-forward cross-correlator noise cancellation device also includes a cross-correlator device coupled to the synthesizer to receive the reference clock signal and the synthesized output clock signal and to cross-correlate the reference clock signal and the synthesized output clock signal to generate a cross-correlated output signal. The open-loop feed-forward cross-correlator noise cancellation device further includes a signal control delay line coupled to the cross-correlator device to generate an anti-phase noise signal based on the cross-correlated output signal to counter uncorrelated phase noise from additional circuitry of the synthesizer.

First claim

What is claimed is:

1 . An open-loop feed-forward cross-correlator noise cancellation device, comprising:
a synthesizer to generate a synthesized output clock signal based at least in part on a reference clock signal; a cross-correlator device coupled to the synthesizer to receive the reference clock signal and the synthesized output clock signal and to cross-correlate the reference clock signal and the synthesized output clock signal to generate a cross-correlated output signal; and a delay line coupled to the cross-correlator device, a delay of the delay line based at least in part on the cross-correlated output signal.

2 . The open-loop feed-forward cross-correlator noise cancellation device of claim 1 , in which the delay line is configured to generate an anti-phase noise signal based at least in part on the cross-correlated output signal to counter uncorrelated phase noise from additional circuitry of the synthesizer.

3 . The open-loop feed-forward cross-correlator noise cancellation device of claim 2 , further comprising a combiner to combine the cross-correlated output signal with a reference signal, in which the anti-phase noise signal is based at least in part on the reference signal and the cross-correlated output signal.

4 . The open-loop feed-forward cross-correlator noise cancellation device of claim 1 , further comprising an open-loop filter coupled between the cross-correlator device and the delay line.

5 . The open-loop feed-forward cross-correlator noise cancellation device of claim 1 , in which the delay line comprises a voltage controlled delay line, a current controlled delay line or a charge controlled delay line.

6 . The open-loop feed-forward cross-correlator noise cancellation device of claim 1 , in which the delay line comprises a low dropout (LDO) regulator and a buffer.

7 . The open-loop feed-forward cross-correlator noise cancellation device of claim 1 , in which the cross-correlator device comprises a phase detector.

8 . The open-loop feed-forward cross-correlator noise cancellation device of claim 1 , in which the synthesizer comprises a phase locked loop, a delay locked loop, or a phase/frequency synthesizer.

9 . The open-loop feed-forward cross-correlator noise cancellation device of claim 1 , in which the open-loop feed-forward cross-correlator noise cancellation device is incorporated in a reference clock signal and synthesizer system for an analog-to-digital converter (ADC), a digital-to-analog converter (DAC), a central processing unit (CPU), a receive block of a wireless communication device or a transmit block of the wireless communication device.

10 . A method to achieve open-loop feed-forward cross-correlator noise cancellation, comprising:
generating a synthesized output clock signal based at least in part on a reference clock signal; cross-correlating the reference clock signal and the synthesized output clock signal to generate a cross-correlated output signal; and generating an anti-phase noise signal based at least in part on the cross-correlated output signal to counter uncorrelated phase noise from circuitry of a synthesizer.

11 . The method to achieve open-loop feed-forward cross-correlator noise cancellation of claim 10 , further comprising filtering out correlated input noise from the reference clock signal leaving the uncorrelated phase noise.

12 . The method to achieve open-loop feed-forward cross-correlator noise cancellation of claim 10 , further comprising combining the cross-correlated output signal with a reference signal, in which the anti-phase noise signal is based at least in part on the reference signal and the cross-correlated output signal.

13 . The method to achieve open-loop feed-forward cross-correlator noise cancellation of claim 10 , in which the method is implemented using an open-loop feed-forward cross-correlator noise cancellation device.

14 . The method to achieve open-loop feed-forward cross-correlator noise cancellation of claim 13 , further comprising incorporating the open-loop feed-forward cross-correlator noise cancellation device in a reference clock signal and synthesizer system for an analog-to-digital converter (ADC), a digital-to-analog converter (DAC), a central processing unit (CPU), a receive block of a wireless communication device or a transmit block of the wireless communication device.

15 . An open-loop feed-forward cross-correlator noise cancellation device, comprising:
means for generating a synthesized output clock signal based at least in part on a reference clock signal; a cross-correlator device, coupled to the synthesized output clock signal generating means, to receive the reference clock signal and the synthesized output clock signal and to cross-correlate the reference clock signal and the synthesized output clock signal to generate a cross-correlated output signal; and means for generating a delay based at least in part on the cross-correlated output signal, the delay generating means coupled to the cross-correlator device.

16 . The open-loop feed-forward cross-correlator noise cancellation device of claim 15 , in which the delay generating means is configured to generate an anti-phase noise signal based at least in part on the cross-correlated output signal to counter uncorrelated phase noise from additional circuitry of the synthesized output clock signal generating means.

17 . The open-loop feed-forward cross-correlator noise cancellation device of claim 16 , further comprising a combiner to combine the cross-correlated output signal with a reference signal, in which the anti-phase noise signal is based at least in part on the reference signal and the cross-correlated output signal.

18 . The open-loop feed-forward cross-correlator noise cancellation device of claim 15 , further comprising an open-loop filter coupled between the cross-correlator device and the delay generating means.

19 . The open-loop feed-forward cross-correlator noise cancellation device of claim 15 , in which the cross-correlator device comprises a phase detector.

20 . The open-loop feed-forward cross-correlator noise cancellation device of claim 15 , in which the open-loop feed-forward cross-correlator noise cancellation device is incorporated in a reference clock signal and synthesizer system for an analog-to-digital converter (ADC), a digital-to-analog converter (DAC), a central processing unit (CPU), a receive block of a wireless communication device or a transmit block of the wireless communication device.

Assignees

• Qualcomm Inc

Inventors

• Lu Yue
• Chen Zuow-Zun
• Yang Jeongsik

Classifications

• H04L7/0012

  by comparing receiver clock with transmitter clock · CPC title

• H04B15/00 Primary

  Suppression or limitation of noise or interference (by means associated with receiver H04B1/10) · CPC title

• H03L1/00 Primary

  Stabilisation of generator output against variations of physical values, e.g. power supply · CPC title

• H03L2207/05

  Compensating for non-linear characteristics of the controlled oscillator · CPC title

• H04B15/06

  by local oscillators of receivers · CPC title