CA2406716A1 - Method and apparatus for compensating local oscillator frequency error - Google Patents

Method and apparatus for compensating local oscillator frequency error Download PDF

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Publication number
CA2406716A1
CA2406716A1 CA002406716A CA2406716A CA2406716A1 CA 2406716 A1 CA2406716 A1 CA 2406716A1 CA 002406716 A CA002406716 A CA 002406716A CA 2406716 A CA2406716 A CA 2406716A CA 2406716 A1 CA2406716 A1 CA 2406716A1
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Canada
Prior art keywords
frequency error
sensor
minimum
mode
readings
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CA002406716A
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French (fr)
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CA2406716C (en
Inventor
Christopher Patrick
Saed G. Younis
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Qualcomm Inc
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Individual
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Publication of CA2406716A1 publication Critical patent/CA2406716A1/en
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Publication of CA2406716C publication Critical patent/CA2406716C/en
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Expired - Lifetime legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION, OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
    • H03L7/00—Automatic control of frequency or phase; Synchronisation
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/13—Receivers
    • G01S19/23—Testing, monitoring, correcting or calibrating of receiver elements
    • G01S19/235—Calibration of receiver components
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03J—TUNING RESONANT CIRCUITS; SELECTING RESONANT CIRCUITS
    • H03J7/00—Automatic frequency control; Automatic scanning over a band of frequencies
    • H03J7/02—Automatic frequency control
    • H03J7/04—Automatic frequency control where the frequency control is accomplished by varying the electrical characteristics of a non-mechanically adjustable element or where the nature of the frequency controlling element is not significant
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION, OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
    • H03L1/00—Stabilisation of generator output against variations of physical values, e.g. power supply
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION, OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
    • H03L7/00—Automatic control of frequency or phase; Synchronisation
    • H03L7/06—Automatic control of frequency or phase; Synchronisation using a reference signal applied to a frequency- or phase-locked loop
    • H03L7/16—Indirect frequency synthesis, i.e. generating a desired one of a number of predetermined frequencies using a frequency- or phase-locked loop
    • H03L7/18—Indirect frequency synthesis, i.e. generating a desired one of a number of predetermined frequencies using a frequency- or phase-locked loop using a frequency divider or counter in the loop
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION, OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
    • H03L1/00—Stabilisation of generator output against variations of physical values, e.g. power supply
    • H03L1/02—Stabilisation of generator output against variations of physical values, e.g. power supply against variations of temperature only
    • H03L1/022—Stabilisation of generator output against variations of physical values, e.g. power supply against variations of temperature only by indirect stabilisation, i.e. by generating an electrical correction signal which is a function of the temperature
    • H03L1/026—Stabilisation of generator output against variations of physical values, e.g. power supply against variations of temperature only by indirect stabilisation, i.e. by generating an electrical correction signal which is a function of the temperature by using a memory for digitally storing correction values
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/69—Spread spectrum techniques
    • H04B1/707—Spread spectrum techniques using direct sequence modulation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/0014—Carrier regulation
    • H04L2027/0016—Stabilisation of local oscillators

Abstract

The frequency error of an oscillator is minimized by characterizing the oscillator. A reference signal from an external source containing a minimal frequency error is provided to an electronic device. The external signal is used as a reference frequency to estimate the frequency error of an internal frequency source. The electronic device monitors parameters that are determined to have an effect on the frequency accuracy of the internal frequency source. Temperature is one parameter known to have an effect on th e frequency of the internal frequency source. The electronic device collects a nd stores the values of the parameters as well as the corresponding output frequency or frequency error of the internal frequency source. The resultant characterization of the internal frequency source is used to compensate the internal frequency source when the internal frequency source is not provided the external reference signal.

Claims (20)

1. A device for compensating Local Oscillator (LO) frequency error comprising:
an LO;
a receiver coupled to the LO for receiving an external frequency source and calculating an LO frequency error based upon the external frequency source;

a minimum of one sensor for monitoring at least one variable that contributes to LO frequency error; and an oscillator characterization circuit for receiving the calculated LO
frequency error and readings from the minimum of one sensor;

wherein the oscillator characterization circuit generates a compensation signal based upon the calculated LO frequency error and readings from the minimum of one sensor.
2. The device of Claim 1 wherein the oscillator characterization circuit applies the compensation signal to the LO to correct the LO frequency error.
3. The device of Claim 1 wherein the oscillator characterization circuit operating in a first mode stores in a memory device the readings from the minimum of one sensor and the calculated LO frequency error and the oscillator characterization circuit operating in a second mode generates the compensation signal.
4. The device of Claim 3 wherein the oscillator characterization circuit generates the compensation signal by comparing a recent set of readings from the minimum of one sensor to the readings stored in the memory device and generates the compensation signal based upon the corresponding calculated LO frequency error saved in the memory device.
5. The device of Claim 3 wherein the oscillator characterization circuit interpolates or extrapolates the readings stored in the memory device to match a recent set of readings from the minimum of one sensor in order to generate an estimated LO frequency error and the oscillator characterization circuit generates the compensation signal based upon the estimated LO frequency error.
6. The device of Claim 1 wherein the receiver is a wireless phone receiver.
7. The device of Claim 6 wherein the wireless phone receiver is adapted to receive Code Division Multiple Access (CDMA) signals.
8. The device of Claim 7 wherein the external frequency source is a CDMA pilot signal.
9. The device of Claim 8 wherein the oscillator characterization circuit operating in a first mode stores in a memory device the readings from the minimum of one sensor and the calculated LO frequency error and the oscillator characterization circuit operating in a second mode generates the compensation signal
10. The device of Claim 9 wherein the oscillator characterization circuit applies the compensation signal to the LO to correct the LO frequency error.
11. The device of Claim 9 wherein the first mode is a wireless phone mode.
12. The device of Claim 11 wherein the second mode is a Global Positioning System (GPS) mode.
13. The device of Claim 9 wherein the minimum of one sensor comprises a temperature sensor.
14. A method for compensating Local Oscillator (LO) frequency error comprising:
monitoring in a first mode a minimum of one sensor reading and an LO frequency error;

compensating in a second mode an estimated LO frequency error based upon the minimum of one sensor reading and the LO frequency error monitored in the first mode.
15. The method of Claim 14 wherein the monitoring step comprises:
receiving an external frequency source;
generating the LO frequency error by comparing the external frequency source to an LO frequency; and receiving readings from the minimum of one sensor.
16. The method of Claim 15 further comprising;
storing the readings from the minimum of one sensor and the corresponding LO frequency error.
17. The method of Claim 16 wherein the compensating step comprises:
receiving a recent set of readings from the minimum of one sensor;
generating the estimated LO frequency error using the recent set of readings from the minimum of one sensor and the readings from the minimum of one sensor received in the first mode;
generating an LO correction signal from the estimated LO frequency error; and applying the LO correction signal to compensate the LO.
18. The method of Claim 14 wherein the external frequency source is a Code Division Multiple Access (CDMA) pilot signal.
19. The method of Claim 18 wherein the minimum of one sensor comprises a temperature sensor.
20. The methods of Claim 14 wherein the second mode is a Global Positioning System (GPS) mode.
CA2406716A 2000-05-08 2001-05-08 Method and apparatus for compensating local oscillator frequency error Expired - Lifetime CA2406716C (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US09/567,803 US6928275B1 (en) 2000-05-08 2000-05-08 Method and apparatus for compensating local oscillator frequency error
US09/567,803 2000-05-09
PCT/US2001/014991 WO2001086316A2 (en) 2000-05-08 2001-05-08 Method and apparatus for compensating local oscillator frequency error

Publications (2)

Publication Number Publication Date
CA2406716A1 true CA2406716A1 (en) 2001-11-15
CA2406716C CA2406716C (en) 2011-01-04

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Family Applications (1)

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CA2406716A Expired - Lifetime CA2406716C (en) 2000-05-08 2001-05-08 Method and apparatus for compensating local oscillator frequency error

Country Status (13)

Country Link
US (1) US6928275B1 (en)
EP (1) EP1290463A2 (en)
JP (1) JP5128747B2 (en)
KR (1) KR100881295B1 (en)
CN (1) CN100383549C (en)
AU (2) AU2001259678B2 (en)
BR (1) BR0110684A (en)
CA (1) CA2406716C (en)
HK (1) HK1056015A1 (en)
IL (1) IL152550A0 (en)
MX (1) MXPA02011012A (en)
RU (1) RU2280261C2 (en)
WO (1) WO2001086316A2 (en)

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Also Published As

Publication number Publication date
JP5128747B2 (en) 2013-01-23
WO2001086316A3 (en) 2002-10-10
HK1056015A1 (en) 2004-01-30
JP2004514877A (en) 2004-05-20
RU2280261C2 (en) 2006-07-20
US6928275B1 (en) 2005-08-09
IL152550A0 (en) 2003-05-29
KR20030003275A (en) 2003-01-09
CN1440509A (en) 2003-09-03
EP1290463A2 (en) 2003-03-12
AU2001259678B2 (en) 2005-12-01
AU5967801A (en) 2001-11-20
BR0110684A (en) 2004-06-22
CN100383549C (en) 2008-04-23
MXPA02011012A (en) 2003-04-25
CA2406716C (en) 2011-01-04
KR100881295B1 (en) 2009-02-03
WO2001086316A2 (en) 2001-11-15

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