Agile clock mechanism and method for ultrawide bandwidth communications system

• US 7,643,533 B2
• Filed: 07/19/2005
• Issued: 01/05/2010
• Est. Priority Date: 05/26/2000
• Status: Expired due to Fees

• Current Assignee: North Star Innovations Inc. (Wi-LAN Inc.)
• Original Assignee: Freescale Semiconductor, Inc. (NXP Semiconductors NV)
• Inventors: McCorkle, John W.
• Primary Examiner(s): Wang, Ted M
• Application Number:
  US11/183,778
• Publication Number:
  US 20050265428A1
• Time in Patent Office: 1,631 Days
• Field of Search: 375/130, 375/147, 375/316, 375/371, 375/376
• US Class Current: 375/130
• CPC Class Codes: G01S 13/0209 Systems with very large relative bandwidth, i.e. larger than 10 %, e.g. baseband, pulse, carrier-free, ultrawideband
• CPC Class Codes: G01S 7/023 Interference mitigation, e.g. reducing or avoiding non-intentional interference with other HF-transmitters, base station transmitters for mobile communication or other radar systems, e.g. using electro-magnetic interference [EMI] reduction techniques auxiliary means for detecting or identifying radar signals or the like G01S7/021; means for anti-jamming G01S7/36
• CPC Class Codes: G01S 7/0232 Avoidance by frequency multiplex
• CPC Class Codes: H04B 1/71635 Transmitter aspects H04B1/7174 takes precedence
• CPC Class Codes: H04B 1/71637 Receiver aspects H04B1/7183 takes precedence
• CPC Class Codes: H04B 1/7172 Pulse shape in general H04L25/03834
• CPC Class Codes: H04L 25/4902 Pulse width modulation; Pulse position modulation
• CPC Class Codes: H04L 27/0004 using wavelets

Abstract

An ultra wide bandwidth communications system, method and computer program product including an ultra wide bandwidth timing generator. The timing generator includes a high frequency clock generation circuit having low phase noise; a low frequency control generation circuit; and a modulation circuit coupled between the high frequency clock generation circuit and the low frequency control generation circuit. The high frequency clock generation circuit generates a plurality of high frequency clock signals. The low frequency control generation circuit generates a plurality of low frequency control signals. The modulation circuit modulates the high frequency clock signals with the low frequency control signals to produce an agile timing signal at a predetermined frequency and phase. The agile timing signal is generated at the predetermined frequency and phase by adjustments to at least one of frequency of the low frequency control signals, phase of the low frequency control signals, frequency of the high frequency clock signals, and phase of the high frequency clock signals.

Claims

1. An ultra wide bandwidth timing generator, comprising:

a high frequency clock generation circuit having low phase noise;

a low frequency control generation circuit; and

a modulation circuit coupled between the high frequency clock generation circuit and the low frequency control generation circuit,

wherein the high frequency clock generation circuit generates a plurality of high frequency clock signals,

the low frequency control generation circuit generates a plurality of low frequency control signals, and

the modulation circuit modulates the high frequency clock signals with the low frequency control signals to produce an agile timing signal at a predetermined frequency and phase by adjustments to at least one of frequency of the low frequency control signals, phase of the low frequency control signals, frequency of the high frequency clock signals, and phase of the high frequency clock signals,

wherein the high frequency clock generation circuit is configured to receive at least one of

a coarse frequency control signal for coarse tuning of the agile timing signal in frequency, and

a fast-modulation control signal for modulating the agile timing signal in frequency.

2. The timing generator of claim 1, wherein the low frequency control generation circuit is configured to receive a phase control signal for controlling the agile timing signal in fine time increments.

3. The timing generator of claim 1, wherein said plurality of high frequency clock signals comprise a first high frequency sinusoidal clock signal and second high frequency sinusoidal clock signal shifted in phase by 900 from the first high frequency sinusoidal clock signal.

4. The timing generator of claim 3, wherein the plurality of low frequency control signals comprise a first low frequency approximately sinusoidal control signal and a second low frequency approximately sinusoidal control signal shifted in phase by approximately 90°

from the first low frequency sinusoidal control signal for controlling a magnitude, in the range of +1 to −

1, of the first high frequency sinusoidal clock signal and the second high frequency sinusoidal clock signal, such that a sum of the first high frequency sinusoidal clock signal and the second high frequency sinusoidal clock signal produces the agile timing signal with a predetermined arbitrary phase between 0 and 2π

.

5. The timing generator of claim 1, wherein the high frequency clock generation circuit is configured to generate a first high frequency sinusoidal clock signal, a second high frequency sinusoidal clock signal and a third high frequency sinusoidal clock signal having approximately 0°

, 120° and

240°

phase relationships, respectively, such that the first through third high frequency sinusoidal clock signals can be positively weighted in the range of 0 to 1 and summed to produce the agile timing signal with any arbitrary phase.

6. The timing generator of claim 5, wherein the low frequency control generation circuit is configured to generate a first low frequency control signal, a second low frequency control signal and a third low frequency control signal to control the amplitudes of the first high frequency sinusoidal clock signal, the second high frequency sinusoidal clock signal and the third high frequency sinusoidal clock signal, respectively, such that the agile timing signal with an arbitrary phase can be generated.

7. An ultra wide bandwidth timing generation method, comprising:

generating a plurality of high frequency clock signals via a high frequency clock generation circuit having low phase noise;

generating a plurality of low frequency control signals via a low frequency control generation circuit;

modulating, via a modulation circuit coupled between the high frequency clock generation circuit and the low frequency control generation circuit, the high frequency clock signals with the low frequency control signals to produce an agile timing signal at a predetermined frequency and phase by adjustments to at least one of at least one of frequency of the low frequency control signals, phase of the low frequency control signals, frequency of the high frequency clock signals, and phase of the high frequency clock signals and

at least one of the following steps;

tuning of the agile timing signal in frequency based on a coarse frequency control signal received by the high frequency clock generation circuit, and

modulating the agile timing signal in frequency based on a fast-modulation control signal received by the high frequency clock generation circuit.

8. The method of claim 7, further comprising:

providing a phase-ramp control signal to the low frequency control generation circuit for fine tuning of the agile timing signal in frequency via a phase accumulator circuit coupled to the low frequency control generation circuit.

9. The method of claim 8, further comprising:

generating the phase-ramp control signal based on a fine frequency control value received by the phase accumulator.

10. An ultra wide bandwidth (UWB) communications receiver, comprising:

a UWB demodulator configured to demodulate a UWB signal containing received data;

a controller coupled to the UWB demodulator; and

a UWB timing generator coupled to the controller and the UWB demodulator, the UWB timing generator configured to generate an agile timing signal provided to the demodulator, the UWB timing generator including;

a high frequency clock generation circuit having low phase noise;

a low frequency control generation circuit; and

a modulation circuit coupled between the high frequency clock generation circuit and the low frequency control generation circuit,

wherein the high frequency clock generation circuit generates a plurality of high frequency clock signals,

the low frequency control generation circuit generates a plurality of low frequency control signals, and

the modulation circuit modulates the high frequency clock signals with the low frequency control signals to produce the agile timing signal provided to the demodulator at a predetermined frequency and phase by adjustments to at least one of frequency of the low frequency control signals, phase of the low frequency control signals, frequency of the high frequency clock signals, and phase of the high frequency clock signals via the controller,

wherein the high frequency clock generation circuit is configured to generate a first high frequency sinusoidal clock signal, a second high frequency sinusoidal clock signal and a third high frequency sinusoidal clock signal having approximately 0°

, 120° and

240°

phase relationships, respectively, such that the first through third high frequency sinusoidal clock signals can be positively weighted in the range of 0 to 1 and summed to produce the agile timing signal with any arbitrary phase.

11. An ultra wide bandwidth timing generator, comprising:

a high frequency clock generation circuit having low phase noise;

a low frequency control generation circuit;

a modulation circuit coupled between the high frequency clock generation circuit and the low frequency control generation circuit; and

a phase-ramp control signal generation circuit configured to provide a phase-ramp control signal to the low frequency control generation circuit for fine tuning of the agile timing signal in frequency,

wherein the high frequency clock generation circuit generates a plurality of high frequency clock signals,

the low frequency control generation circuit generates a plurality of low frequency control signals, and

the modulation circuit modulates the high frequency clock signals with the low frequency control signals to produce an agile timing signal at a predetermined frequency and phase by adjustments to at least one of frequency of the low frequency control signals, phase of the low frequency control signals, frequency of the high frequency clock signals, and phase of the high frequency clock signals,

wherein the high frequency clock generation circuit is configured to receive at least one of

a coarse frequency control signal for coarse tuning of the agile timing signal in frequency, and

a fast-modulation control signal for modulating the agile timing signal in frequency.

12. An ultra wide bandwidth timing generator, as recited in claim 11, wherein the phase-ramp control signal generation circuit is configured to receive a phase control signal for controlling the agile timing signal in fine time increments.

13. The timing generator of claim 11,

wherein the high frequency clock generation circuit generates a reference clock signal, and

wherein the reference clock signal is provided to the low frequency control generation circuit and the phase-ramp control signal generation circuit.

14. The timing generator of claim 13, wherein the phase-ramp control signal generation circuit is configured to receive a fine frequency control value for generating the phase-ramp control signal.

15. The timing generator of claim 11, wherein the low frequency control generation circuit is configured to receive a phase control signal for controlling the agile timing signal in fine time increments.

16. The timing generator of claim 11, wherein said plurality of high frequency clock signals comprise a first high frequency sinusoidal clock signal and second high frequency sinusoidal clock signal shifted in phase by 90°

from the first high frequency sinusoidal clock signal.

17. The timing generator of claim 16, wherein the plurality of low frequency control signals comprise a first low frequency approximately sinusoidal control signal and a second low frequency approximately sinusoidal control signal shifted in phase by approximately 90°

from the first low frequency sinusoidal control signal for controlling a magnitude, in the range of +1 to −

1, of the first high frequency sinusoidal clock signal and the second high frequency sinusoidal clock signal, such that a sum of the first high frequency sinusoidal clock signal and the second high frequency sinusoidal clock signal produces the agile timing signal with a predetermined arbitrary phase between 0 and 2π

.

18. The timing generator of claim 11, wherein the high frequency clock generation circuit is configured to generate a first high frequency sinusoidal clock signal, a second high frequency sinusoidal clock signal and a third high frequency sinusoidal clock signal having approximately 0°

, 120° and

240°

phase relationships, respectively, such that the first through third high frequency sinusoidal clock signals can be positively weighted in the range of 0 to 1 and summed to produce the agile timing signal with any arbitrary phase.

19. The timing generator of claim 18, wherein the low frequency control generation circuit is configured to generate a first low frequency control signal, a second low frequency control signal and a third low frequency control signal to control the amplitudes of the first high frequency sinusoidal clock signal, the second high frequency sinusoidal clock signal and the third high frequency sinusoidal clock signal, respectively, such that the agile timing signal with an arbitrary phase can be generated.