WO1992011704A1 - Appareil et procede de production de signaux en quadrature - Google Patents

Appareil et procede de production de signaux en quadrature Download PDF

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Publication number
WO1992011704A1
WO1992011704A1 PCT/US1991/009587 US9109587W WO9211704A1 WO 1992011704 A1 WO1992011704 A1 WO 1992011704A1 US 9109587 W US9109587 W US 9109587W WO 9211704 A1 WO9211704 A1 WO 9211704A1
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WO
WIPO (PCT)
Prior art keywords
phase
exclusive
signals
differential
signal
Prior art date
Application number
PCT/US1991/009587
Other languages
English (en)
Inventor
Mark F. Hilbert
Steven F. Gillig
Joseph P. Heck
Original Assignee
Motorola, Inc.
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Motorola, Inc. filed Critical Motorola, Inc.
Priority to BR919106406A priority Critical patent/BR9106406A/pt
Publication of WO1992011704A1 publication Critical patent/WO1992011704A1/fr
Priority to FI923760A priority patent/FI923760A0/fi

Links

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
    • H03L7/06—Automatic control of frequency or phase; Synchronisation using a reference signal applied to a frequency- or phase-locked loop
    • H03L7/08—Details of the phase-locked loop
    • H03L7/081—Details of the phase-locked loop provided with an additional controlled phase shifter
    • H03L7/0812—Details of the phase-locked loop provided with an additional controlled phase shifter and where no voltage or current controlled oscillator is used
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03B—GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING, BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN A NON-SWITCHING MANNER; GENERATION OF NOISE BY SUCH CIRCUITS
    • H03B27/00—Generation of oscillations providing a plurality of outputs of the same frequency but differing in phase, other than merely two anti-phase outputs
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H11/00—Networks using active elements
    • H03H11/02—Multiple-port networks
    • H03H11/16—Networks for phase shifting
    • H03H11/22—Networks for phase shifting providing two or more phase shifted output signals, e.g. n-phase output

Definitions

  • the present invention relates generally to signal generators, and, more particularly, to a signal generator providing differential quadrature signals and maintaining these signals precisely in a 90° phase relationship.
  • a precise 90° phase relationship having a high degree of accuracy is a necessity for implementing quadrature modulated transmit signals and quadrature demodulated receive signals.
  • Two such quadrature systems may include a single sideband mixer and a coherent detector.
  • the output of an ideal single mixer comprises a desired carrier frequency and an image frequency.
  • the image frequency can be surpressed. Deviation from 90° causes imperfect surpression of an image frequency and degradation of the modulator or demodulator function.
  • conventional quadrature signal generators have an accuracy tolerance which depends on the tolerance of the components forming the circuit. Since a high accuracy of component values is difficult to achieve, the quadrature phase is different from ideal quadrature.
  • Quadrature signal generators typically have the problem of accurately detecting a quadrature condition with an input signal having a wide range of amplitudes and different harmonic content. They also have the problem of accurately maintaining a quadrature condition over a wide range of frequencies and temperatures.
  • Another problem is in generating a pair of quadrature outputs such that the amplitudes and shapes of the phase- shifted signals are equal to the amplitudes and shapes of the non-phase-shifted signals.
  • a further problem is the difficulty of implementing a quadrature signal generator well suited for driving balanced mixers. Balanced mixers offer better supply rejection and better accuracy when accompanying circuitry is also balanced. Thus, a daunting challenge is to conceive of a precision quadrature signal generator overcoming the problematic conditions described above.
  • FIG. 1 is a block diagram of a phase-locking precision quadrature signal generator constructed in accordance with the present invention.
  • FIG. 2 is a circuit representing a voltage controlled phase-shift network included in the phase-locking precision quadrature signal generator of FIG. 1.
  • FIG. 3 is a circuit representing an exclusive-OR phase detector included in the phase-locking precision quadrature signal generator of FIG. 1 .
  • An apparatus produces in-phase and quadrature-phase signals from a differential input signal. Differential quadrature signals are generated in response to a differential input signal. A variation from 90° between the phases of the differential quadrature signals is detected. A control signal is generated in response to the detected variation. The phases of the differential quadrature signals are adjusted in response to the control signal.
  • This invention may be advantageously utilized in a transmitter or a receiver requiring quadrature signals.
  • the preferred embodiment of the present invention is particularly suited for driving balanced mixers.
  • a balanced mixer configuration offers the advantages of better supply rejection and better accuracy when accompanying circuitry is also balanced.
  • differential processing of in-phase and quadrature-phase signal components are implemented throughout the quadrature signal generator as described in the preferred embodiment.
  • the use of a phase-locked loop employing a low pass filter, a voltage controlled phase-shift network, limiters, a novel precision exclusive-OR phase detector, a second low pass filter, a precision voltage to current converter, and a loop filter produces an improvement over conventional quadrature signal generators.
  • Utilizing an advanced BiCMOS fabrication process makes it possible to implement the entire function of the phase-locked loop on the same integrated circuit.
  • the BiCMOS process combines the advantages of bipolar and CMOS technology.
  • FIG. 1 A block diagram of the phase-locked loop 100 generating differential in- phase and differential quadrature-phase signals constructed in accordance with the present invention is shown in FIG. 1.
  • the differential quadrature signals, (I,. ' ) and (Q/Q ' ), can be used as the local oscillator inputs in a quadrature modulator which uses balanced mixers, or to down-convert a quadrature modulated radio signal to base band in a direct conversion receiver.
  • the differential input signals, (V,V) are applied to low pass filter 101 to generate filtered differential signals, (v/v ' ).
  • the differential input signals, (V,V) each have an AC signal component which are180° out of phase from each other and DC signal component which are the same.
  • the low pass filter 101 contributes to the wave-shape matching of the phase-shifted and non-phase-shifted signals by filtering out any second harmonic present in the differential input signals, (V.V).
  • the filtered differential signals, (v,v') are coupled to a voltage controlled, phase-shift network 103 which generates two pairs of differential phase-shifted signals, (X . X ' ) and (Y,Y ' ).
  • the differential phase-shifted signals, (X,X ' )_ are 180° out of phase from each other and likewise, differential phase-shifted signals, (Y,Y ' ), are also 180° out of phase from each other.
  • the phase difference between each pair of signals is a function of a control voltage VCNTL- Differential phase-shifted signals, (X,X ' ) and (Y,Y ' ), are then processed with identical limiters 105 and 107 producing differential quadrature signals (l,l ' ) and (Q/Q ' ).
  • the limiters 105 and 107 ensure that the differential quadrature signals, (I.T) and (Q/Q ' ), have essentially the same wave shapes and amplitudes. These differential quadrature signals having a precise 90° quadrature relationship are used to drive the transmitting and receiving circuitry.
  • the differential quadrature signals are also coupled to the novel precision exclusive-OR phase detector 109, having detected differential output, (XOR.XOR ' ), with an average DC value proportional to the phase error from ideal quadrature.
  • a second low pass filter 1 11 extracts the average DC value from the detected differential outputs, (XOR.XOR ' ), generated by the exclusive-OR phase detector 109.
  • the second low pass filter 111 is coupled to a precision voltage to current (V to I) converter 113 which determines the difference between the two DC levels and translates the result into a current signal at line 114.
  • a loop filter 115 converts the current signal at line 1 14 into the voltage control signal, VCNTL, and also maintains loop stability.
  • the control voltage, VCNTL is fed back into the voltage controled phase-shift network 103 to maintain precision quadrature between differential quadrature signals, (I.T) and (Q/Q ' ),at the outputs of limiters 105 and 107.
  • This phase-locked loop is unique in that it employs a voltage controlled phase-shifter (VPS) rather than a conventional voltage controlled oscillator (VCO).
  • phase-locked loop 100 The problem of generating a pair of differential quadrature output signals such that the amplitudes and shapes of the phase-shifted signals are equal to the amplitudes and shapes of the non-phase-shifted signals is overcome utilizing a combination of elements in the phase-locked loop 100.
  • the voltage controlled phase-shift network 103 preserves its input amplitude such that the fundamental component of each pair of differential phase- shifted signals, (X,X ' ) and (Y,Y ' ), have the same amplitude, however, if the filtered differential input to the voltage controlled phase-shift network 103 has high harmonic content, the harmonics in the (X,X ' ) signals will be phase- shifted by more than 90° and cause the shape and zero- crossing slopes of the (Y,Y ' ) signals to be different from that of the (X,X ' ) signals.
  • the limiters correct for the amplitude distortion such that the limiters differential phase-shifted signals, (I.T) and (Q/Q ' ), are nearly identical in wave shape.
  • the low pass filter 101 preceding the voltage control phase-shift network 103 also contributes to the wave shape matching by filtering out any second harmonic present in the differential input signals, (V.V).
  • a second harmonic distortion would not only disrupt the 50% duty cycle of the differential quadrature signals, (U ' ) and (Q/Q'), but would also cause their duty cycles not to match. Matching wave shapes are essential when using those signals as local oscillators in balanced mixer applications requiring precise image cancellation.
  • a quadrature phase-shift in the filtered differential signal, (v,v ' ) is generated using the voltage controled phase-shift network 103 as shown in FIG. 2.
  • the phase- shift is accomplished with a bridge RC arrangement driven in a double-ended configuration by a differential transistor amplifier.
  • the Laplace transform for differential phase-shifted signal, Y is:
  • the Laplace transform for Y ' is
  • PMOS transistors 201 and 203 are biased in the linear (resistive) region to create a voltage controlled phase-shifter.
  • the PMOS gate voltages are varied to provide the phase-shift.
  • the PMOS transistors 201 and 203 were also instrumental in solving the problem of accurately maintaining a quadrature condition over a wide range of frequencies and temperatures.
  • the gate-source voltage of the PMOS transistors 201 and 203, adjusted by the voltage control signal, VCNTL, is represented by Nominal sensitivity using the PMOS transistors 201 and 203 now becomes about 100° per volt. This will not only cover variations in resistance and capacitance tolerance and temperature but also allows phase-locked quadrature operation over a large range of input frequencies.
  • XOR 1 and XOR 2 Two standard current mode logic (CML) exclusive-OR gates are represented by XOR 1 and XOR 2.
  • the first exclusive-OR gate, XOR 1 comprises 6 NPN transistors 301 through 306.
  • the second exclusive-OR gate, XOR 2 is represented by 6 NPN transistors 307 through 312. Diodes 313 - 316 and current sources 317 - 320 are provided to keep the transistors (305, 306, 31 1 , 312) operating in their active region.
  • the two exclusive-OR gates, XOR 1 and XOR 2 are connected in such a way that the differential in-phase signals, (I,.
  • the differential quadrature-phase input signals, (Q/Q ' ), are coupled to the upper transistor pairs (NPN transistors 307 through 310) of the second gate, XOR 2, and also coupled in parallel with the lower transistor pair (NPN transistors 305 and 306) of the first gate, XOR 1 .
  • single-ended input signals (l “ ,Q " ), have an AC and a DC signal component which are coupled to the same exclusive- OR inputs as input signals, (l,Q), in the preferred embodiment.
  • Input signals, (. '" .Q “' ), have only a DC signal component corresponding to the DC signal component of single-ended input signals, (l “ ,Q " ).
  • -",Q”'), are coup
  • phase error from ideal quadrature may be determined by either of two methods. The first method detects the phase error by determining the difference between the two outputs. The second method detects the phase error by determining the difference between one output and a independent DC reference signal.
  • the novel quadrature signal generator can accurately generate a precise quadrature condition with an input signal having a wide range of amplitudes and different harmonic content. It can also accurately maintain a quadrature condition over a wide range of frequencies and temperatures.
  • the amplitudes and shapes of the phase-shifted signals are equal to the amplitudes and shapes of the non-phase-shifted signals.
  • the differential quadrature signals generated may be used advantageously with balanced mixers thereby improving transmitter and receiver performance.

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  • Digital Transmission Methods That Use Modulated Carrier Waves (AREA)

Abstract

L'invention se rapporte à un générateur de signaux en quadrature, qui produit des signaux en phase différentiels, (I, I'), et des signaux à phase en quadrature différentiels, (Q/Q'), selon une relation en quadrature précisément de 90°. Une configuration à boucle verrouillée en phase (100) de ce générateur comprend un réseau à déplacement de phase commandé en tension (103) et un nouveau détecteur de phase OU exclusif (109). Le réseau à déplacement de phase commandé en tension (103) génère un déplacement de phase pour les signaux en quadrature différentiels, (I, I') et (Q/Q'). Le nouveau détecteur de phase OU exclusif (109) détermine l'erreur de phase entre les signaux en quadrature différentiels, (I, I') et (Q/Q'). L'erreur de phase est mise en relation avec un signal de commande de tension, VCNTL, couplé en retour au réseau à déplacement de phase commandé en tension (103), afin de conserver une relation de phase précise de 90° entre les signaux en quadrature différentiels, (I, I') et (Q/Q').
PCT/US1991/009587 1990-12-21 1991-12-18 Appareil et procede de production de signaux en quadrature WO1992011704A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
BR919106406A BR9106406A (pt) 1990-12-21 1991-12-18 Aparelho e processo para produzir sinais de fase de quadratura,e aparelho e processo para detectar variacao de 90 0 fase entre sinais e quadratura
FI923760A FI923760A0 (fi) 1990-12-21 1992-08-20 Anordning och foerfarande foer generering av kvadratursignaler.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US63370190A 1990-12-21 1990-12-21
US633,701 1990-12-21

Publications (1)

Publication Number Publication Date
WO1992011704A1 true WO1992011704A1 (fr) 1992-07-09

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1991/009587 WO1992011704A1 (fr) 1990-12-21 1991-12-18 Appareil et procede de production de signaux en quadrature

Country Status (8)

Country Link
JP (1) JPH05505297A (fr)
AU (1) AU9179691A (fr)
BR (1) BR9106406A (fr)
CA (1) CA2073347C (fr)
FR (1) FR2670975A1 (fr)
IT (1) IT1250974B (fr)
MX (1) MX174064B (fr)
WO (1) WO1992011704A1 (fr)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0660512A1 (fr) * 1993-12-22 1995-06-28 Philips Composants Et Semiconducteurs Amplificateur déphaseur et son application à un circuit recombineur
WO1996021270A1 (fr) * 1994-12-30 1996-07-11 Philips Electronics N.V. Circuit et procede de generation de signaux en quadrature exacte
WO2001010029A1 (fr) * 1999-08-03 2001-02-08 Cambridge Silicon Radio Ltd. Agencement de decalage de phase
WO2002051091A1 (fr) * 2000-12-21 2002-06-27 Intersil Americas Inc. Detection et correction d'erreur de phase pour des signaux differentiels
US7271622B2 (en) * 2004-06-10 2007-09-18 Theta Microelectronics, Inc. Quadrature voltage controlled oscillators with phase shift detector
EP2220769A1 (fr) * 2007-11-28 2010-08-25 Motorola, Inc. Procédé et appareil de génération de fréquence reconfigurable
USRE42799E1 (en) 2000-10-02 2011-10-04 Intellectual Ventures I Llc Packet acquisition and channel tracking for a wireless communication device configured in a zero intermediate frequency architecture
EP4167488A1 (fr) * 2021-10-13 2023-04-19 MediaTek Inc. Filtre polyphasé doté d'une technique d'amélioration d'erreur de phase

Families Citing this family (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11505987A (ja) * 1995-05-26 1999-05-25 ランバス・インコーポレーテッド 直交クロック発生器内で使用される移相器
GB2361123A (en) 2000-04-04 2001-10-10 Nokia Mobile Phones Ltd Polyphase filters in silicon integrated circuit technology
FR2809266B1 (fr) 2000-05-19 2002-10-11 St Microelectronics Sa Procede et dispositif de controle du dephasage entre quatre signaux mutuellement en quadrature de phase
KR100351057B1 (ko) * 2000-09-26 2002-09-05 삼성전자 주식회사 주파수의 체배성능을 향상시키기 위한 검출제어부를구비하는 주파수 체배회로
US6891440B2 (en) * 2000-10-02 2005-05-10 A. Michael Straub Quadrature oscillator with phase error correction
US8615205B2 (en) 2007-12-18 2013-12-24 Qualcomm Incorporated I-Q mismatch calibration and method
US8970272B2 (en) 2008-05-15 2015-03-03 Qualcomm Incorporated High-speed low-power latches
US8712357B2 (en) 2008-11-13 2014-04-29 Qualcomm Incorporated LO generation with deskewed input oscillator signal
US8718574B2 (en) 2008-11-25 2014-05-06 Qualcomm Incorporated Duty cycle adjustment for a local oscillator signal
US8847638B2 (en) 2009-07-02 2014-09-30 Qualcomm Incorporated High speed divide-by-two circuit
US8791740B2 (en) 2009-07-16 2014-07-29 Qualcomm Incorporated Systems and methods for reducing average current consumption in a local oscillator path
US8854098B2 (en) 2011-01-21 2014-10-07 Qualcomm Incorporated System for I-Q phase mismatch detection and correction
US9154077B2 (en) 2012-04-12 2015-10-06 Qualcomm Incorporated Compact high frequency divider

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US4313089A (en) * 1980-03-31 1982-01-26 Motorola, Inc. Precision quadrature analog phase detector
US4878251A (en) * 1985-04-29 1989-10-31 Plessey Overseas Limited Interference signal suppressor for a radio receiver
US4908532A (en) * 1986-09-16 1990-03-13 Plessey Overseas Limited Quadrature signals generator
US5039889A (en) * 1989-08-19 1991-08-13 U.S. Philips Corp. Phase comparison circuit

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DE3819930A1 (de) * 1988-06-11 1989-12-21 Thomson Brandt Gmbh Schaltungsanordnung zur einstellung der phasenlage eines signals
DE3829164C1 (fr) * 1988-08-27 1989-08-10 Ant Nachrichtentechnik Gmbh, 7150 Backnang, De
NL8802531A (nl) * 1988-10-14 1990-05-01 Philips Nv Fasedetector en frequentiedemodulator voorzien van zulk een fasedetector.

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4313089A (en) * 1980-03-31 1982-01-26 Motorola, Inc. Precision quadrature analog phase detector
US4878251A (en) * 1985-04-29 1989-10-31 Plessey Overseas Limited Interference signal suppressor for a radio receiver
US4908532A (en) * 1986-09-16 1990-03-13 Plessey Overseas Limited Quadrature signals generator
US5039889A (en) * 1989-08-19 1991-08-13 U.S. Philips Corp. Phase comparison circuit

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0660512A1 (fr) * 1993-12-22 1995-06-28 Philips Composants Et Semiconducteurs Amplificateur déphaseur et son application à un circuit recombineur
US5877643A (en) * 1993-12-22 1999-03-02 U.S. Philips Corporation Phase shift amplifier and its applications to a recombining circuit
WO1996021270A1 (fr) * 1994-12-30 1996-07-11 Philips Electronics N.V. Circuit et procede de generation de signaux en quadrature exacte
US6680639B1 (en) 1999-08-03 2004-01-20 Cambridge Silicon Radio Ltd. Phase shifting arrangement for generating mutually orthogonal signals
WO2001010029A1 (fr) * 1999-08-03 2001-02-08 Cambridge Silicon Radio Ltd. Agencement de decalage de phase
US6674998B2 (en) 2000-10-02 2004-01-06 Intersil Americas Inc. System and method for detecting and correcting phase error between differential signals
USRE42799E1 (en) 2000-10-02 2011-10-04 Intellectual Ventures I Llc Packet acquisition and channel tracking for a wireless communication device configured in a zero intermediate frequency architecture
WO2002051091A1 (fr) * 2000-12-21 2002-06-27 Intersil Americas Inc. Detection et correction d'erreur de phase pour des signaux differentiels
US7271622B2 (en) * 2004-06-10 2007-09-18 Theta Microelectronics, Inc. Quadrature voltage controlled oscillators with phase shift detector
EP2220769A1 (fr) * 2007-11-28 2010-08-25 Motorola, Inc. Procédé et appareil de génération de fréquence reconfigurable
EP4167488A1 (fr) * 2021-10-13 2023-04-19 MediaTek Inc. Filtre polyphasé doté d'une technique d'amélioration d'erreur de phase
US11811413B2 (en) 2021-10-13 2023-11-07 Mediatek Inc. Poly phase filter with phase error enhance technique
TWI833335B (zh) * 2021-10-13 2024-02-21 聯發科技股份有限公司 濾波電路及多相濾波器

Also Published As

Publication number Publication date
ITRM910965A0 (it) 1991-12-20
JPH05505297A (ja) 1993-08-05
BR9106406A (pt) 1993-05-04
IT1250974B (it) 1995-04-24
MX9102719A (es) 1992-06-01
AU9179691A (en) 1992-07-22
CA2073347C (fr) 1995-05-09
FR2670975B1 (fr) 1995-03-17
FR2670975A1 (fr) 1992-06-26
MX174064B (es) 1994-04-18
ITRM910965A1 (it) 1993-06-20

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