CN102857221B - The carrier wave leakage calibration method of phaselocked loop, wideband transmitter and wideband transmitter - Google Patents
The carrier wave leakage calibration method of phaselocked loop, wideband transmitter and wideband transmitter Download PDFInfo
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- CN102857221B CN102857221B CN201110181182.3A CN201110181182A CN102857221B CN 102857221 B CN102857221 B CN 102857221B CN 201110181182 A CN201110181182 A CN 201110181182A CN 102857221 B CN102857221 B CN 102857221B
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- frequency
- voltage controlled
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- calibration
- locking
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Classifications
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- 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
- H03L7/099—Details of the phase-locked loop concerning mainly the controlled oscillator of the loop
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- 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
Abstract
The invention discloses the carrier wave leakage calibration method of a kind of phaselocked loop, wideband transmitter and wideband transmitter, wherein phaselocked loop includes：Phase discriminator, loop filter and multiple voltage controlled oscillators, phase discriminator is to loop filter output signal, and loop filter is selectively to one of any output signal of multiple voltage controlled oscillators.The wideband transmitter proposed by the present invention supported by broadband phase-looked loop may operate in various modes, adapt to the development of mechanics of communication and the demand of supplier.
Description
Technical field
The present invention relates to mobile communication technology field, more particularly to a kind of phaselocked loop, wideband transmitter and wideband transmitter
Carrier wave leakage calibration method.
Background technology
In moving communicating field, transmitter applies are in GSM (global system for mobile communications), UMTS (universal mobile communications systems
System), in the various kinds of mobile communication system such as CDMA (CDMA) and LTE (Long Term Evolution), the course of work of emitter is as follows：
First, the data signal from base band is converted into analog baseband signal；
Then, filtering and the up-conversion of signal are completed；
Finally, the radiofrequency signal after frequency conversion is launched by antenna by radio-frequency power amplifier.
In field of mobile communication, although the technology comparative maturity of emitter, be typically only operable on single frequency range and
Pattern, function is relatively fewer, and not enough, expandability is also limited for flexibility.
In addition, in conversion process, some garbage signals, such as local oscillator leakage signal, sideband letter inevitably occur
Number etc..These garbage signals may influence emitter subsequent power amplifying circuit, cause transmitter spectrum transmitting not meet agreement
The regulation of standard, in addition, after carrier wave leakage signal and transmission signal ingoing power amplifier simultaneously, being led because power amplifier is non-linear
Intermodulation deteriorates between causing them, may influence digital pre-distortion effect.
The content of the invention
Let out the technical problem to be solved in the present invention is to provide the carrier wave of a kind of phaselocked loop, wideband transmitter and wideband transmitter
Reveal calibration method, the rate-adaptive pacemaker scope of emitter can be improved.
In order to solve the above technical problems, a kind of phaselocked loop of method of the present invention, including：Phase discriminator, loop filter and many
Individual voltage controlled oscillator, wherein, phase discriminator is to loop filter output signal, and loop filter is selectively to multiple VCOs
One of any output signal of device.
Further, in addition at least one variable reactive component, variable reactive component is divided equally with multiple voltage controlled oscillators
Do not connect.
Further, in addition to one or more frequency dividers, frequency divider be connected to the output end of voltage controlled oscillator there is provided point
Output signal after frequency.
Further, in multiple voltage controlled oscillators, adjacent voltage controlled oscillator exists in desired operating temperature range
Overlaid frequency.
Further, a kind of wideband transmitter, including：I/Q modulator and phaselocked loop, phaselocked loop are connected with I/Q modulator, are
I/Q modulator provides local oscillation signal, wherein, phaselocked loop includes：Phase discriminator, loop filter and multiple voltage controlled oscillators, wherein,
Phase discriminator is to loop filter output signal, and loop filter is selectively believed to one of any output of multiple voltage controlled oscillators
Number.
Further, phaselocked loop also includes at least one variable reactive component, variable reactive component and multiple VCOs
Device is respectively connected.
Further, in multiple voltage controlled oscillators, adjacent voltage controlled oscillator is all deposited in desired operating temperature range
In overlaid frequency.
Further, the carrier wave leakage calibration method of a kind of wideband transmitter, applied to including multiple voltage controlled oscillators
In wideband transmitter, including：
The overlapping frequency range of adjacent voltage controlled oscillator in multiple voltage controlled oscillators is calculated, judges calibration frequency whether in weight
In folded frequency range, if it is, from adjacent voltage controlled oscillator, voltage controlled oscillator locking is specified for calibration frequency；
After voltage controlled oscillator locking is specified for calibration frequency, local oscillator letter is provided for the I/Q modulator of wideband transmitter
Number, and complete to calibrate the carrier wave leakage of I/Q modulator by being adjusted residual baseband, and preserve calibration data.
Further, voltage controlled oscillator locking is specified to include for calibration frequency：
Judgment threshold is calculated according to the locking upper limiting frequency of adjacent voltage controlled oscillator and locking lower frequency limit；
Calibration frequency is compared with judgment threshold, if calibration frequency is less than judgment threshold, specified adjacent voltage-controlled
The less voltage controlled oscillator locking of lower frequency limit is locked in oscillator；If calibrating frequency is more than judgment threshold, specify adjacent
The larger voltage controlled oscillator locking of upper limiting frequency is locked in voltage controlled oscillator.
Further, in addition to：
Before the overlapping frequency range of adjacent voltage controlled oscillator in calculating multiple voltage controlled oscillators, also need determination multiple voltage-controlled
The frequency coverage of oscillator；
It is school according to the frequency coverage of multiple voltage controlled oscillators when calibrating frequency not in overlapping frequency range
Quasi- frequency specifies voltage controlled oscillator locking.
Further, in addition to：
Specified for calibration frequency after voltage controlled oscillator locking, record the numbering of voltage controlled oscillator, frequency order is put receiving
When, put frequency is judged whether in overlapping frequency range, if according to the numbering of voltage controlled oscillator, called corresponding
Voltage controlled oscillator, and enable corresponding calibration data.
In summary, it is proposed by the present invention that various modes may operate in by the broadband PLL wideband transmitters supported, adapt to
The development of mechanics of communication and the demand of supplier.
Brief description of the drawings
Fig. 1 is wideband transmitter system block diagram；
Fig. 2 is conventional phase locked loops process chart；
Fig. 3 proposes broadband phase-looked loop process chart for the present invention；
Fig. 4 is I/Q modulator process chart；
Fig. 5 proposes wideband transmitter carrier wave leakage calibration flow chart for the present invention；
Fig. 6 is that present embodiment proposes that wideband transmitter carrier wave leakage enables calibration data flow chart.
Embodiment
Fig. 1 show the wideband transmitter of the support multiple types of present embodiment, including：The ways of IQ two of high sampling rate
Weighted-voltage D/A converter (DAC), IQ two-way low pass filter (LPF), broadband phase-looked loop (PLL), wide band radio-frequency I/Q modulator (IQ
Modulator), six parts of controllable gain radio frequency amplifier (DVGA) and wideband power amplifer (PA).Present embodiment
Outstanding feature is to use broadband phase-looked loop (PLL), and the local oscillation signal in broadband is provided to I/Q modulator come real by broadband phase-looked loop
Existing wideband transmitter.
Fig. 2 is the structure of traditional narrow phaselocked loop, and Fig. 3 is the structure of broadband phase-looked loop, and phaselocked loop is the phase of a closed loop
Position error control system, the phase difference between comparator input signal and voltage controlled oscillator output signal produces error control voltage
To adjust the frequency of voltage controlled oscillator, to reach with input signal with frequency.
Present embodiment by phaselocked loop integrated multiple voltage controlled oscillators (VCO) realize wide-band tuning, broadband lock
The operation principle of phase ring is identical with narrow band phase lock loop, is all the phase between comparator input signal and voltage controlled oscillator output signal
Difference, produces error control voltage to adjust broadband phase-looked loop in the frequency of voltage controlled oscillator, present embodiment and existing narrow
Maximum difference with phaselocked loop is the tuning range difference to VCO.Broadband VCO tuning range is realized based on following three points：
(1) only comprising a VCO inside traditional phase-locked loop circuit, and collect inside the broadband phase-looked loop of present embodiment
Into multiple VCO tunings, in phase locking process, suitable VCO can be selected to lock in multiple VCO, spliced by multiple VCO
Realize wide-band tuning.Because VCO coverings frequency range can change and processing technology upper and lower translation with high/low temperature, in many VCO are integrated, often
Frequency overlapping range will have sufficient surplus just to can guarantee that broadband PLL in complete warm scope full frequency band locking between lower two VCO of temperature.
(2) phaselocked loop includes at least one variable component (being to show in figure), and the reactance of variable component is usually voltage electricity
Flat function.Comprising one group of variable component in present embodiment, each VCO can with it is any in this group of reactance component
Wide-band tuning is realized in one collocation.
(3) conventional phase locked loops are that voltage controlled oscillator is directly exported, and present embodiment middle width strip phaselocked loop final stage includes one group
Optional frequency divider, can directly export voltage controlled oscillator, can also be in two divided-frequency, the rear output such as four frequency dividings.
By the way that above-mentioned many VCO are covered, variable component tune and export optional frequency divider combine can realize VCO from
Hundreds of million arrive several G Broadband emission.
Present embodiment also solves broadband phase-looked loop carrier wave leakage when different VCO are locked and calibrates the problem of failing.Fig. 4
For I/Q modulator fundamental diagram, if the IQ baseband signals and local oscillation signal of modulator input all do not have for ideal sine wave
Amplitude-phase distortion, then be output as preferable single sideband singal in the absence of carrier wave leakage after modulated device frequency conversion.But practical application
All there is amplitude and phase distortion in the local oscillation signal of middle IQ baseband signals and process phase shifter, cause modulator to include nothing in exporting
Carrier wave leakage signal, must carry out calibration suppression to carrier wave leakage in wideband transmitter application, reach the spuious index of system
It is required that.
Modulator inputs I, and Q and local oscillation signal are represented with equation below, wherein A1A2Represent baseband amplitude, A1It is not equal to A2
Baseband amplitude is uneven,Represent baseband phase,It is not equal toBaseband phase is uneven, B1B2Represent residual baseband,
C1C2Represent LO amplitudes, C1It is not equal to C2LO amplitude imbalances, θ1θ2Represent LO phases, θ1It is not equal to θ2LO unbalance in phase, D1D2
Represent LO DC components.
fL0_ I (t)=C1cos(wct+θ1)+D1
fL0_ Q (t)=C2sin(wct+θ2)+D2Modulator is exported：
Wherein carrier wave leakage is：
Carrier wave leakage is relevant with the DC component of base band and the amplitude imbalance of local oscillation signal it can be seen from formula, when
B1C1=B2C2,When, carrier wave leakage is minimum, and carrier wave leakage calibration process is adjustment residual baseband B1B2So that
Base band direct current offset B equal with LO amplitude products1C1=B2C2, carrier wave leakage amplitude minimum.
Due to only one of which VCO in traditional PLL, VCO gain is fixed, and local oscillator amplitude imbalance is fixed, and carrier wave leakage is only
It is related to base band direct current offset.But due to being internally integrated multiple VCO in broadband PLL designs, in order to ensure that broadband VCO is effective
Frequency overlapping ranges are relatively wide between covering full frequency band, VCO, so will result in frequency in crossover region random on two VCO
The situation of locking, comes difficult to carrier wave leakage calibration tape.Due to the frequency in crossover region, as phaselocked loop power-on and power-off can be random
Any one VCO lockings in crossover region are selected, if the VCO of calibration is different with the VCO enabled, due between VCO gain
Difference can cause local oscillation signal changes in amplitude, the pass that this amplitude product is equal when residual baseband is with calibration when breaking calibration
System, causes calibration data to fail, carrier wave leakage does not reach system requirements.
Present embodiment is by specifying frequency in crossover region to select a fixed VCO to lock, it is ensured that frequency in overlapping region
IQ calibration data continuously effectives, and to frequency reasonable distribution VCO in overlapping region, prevent environmental change from causing phaselocked loop losing lock
Influence emitter normal work.
This problem of carrier wave leakage calibration failure provides solution when being covered for many VCO, as Fig. 5 is broadband VCO
Carrier wave leakage calibrates flow, including：
Step 501：It is electric on emitter, software loading and each module initialization；
Step 502：Determine the frequency coverage of each VCO inside the PLL of broadband；
By output minimum and maximum frequencies of the VCO with the determination VCO that is connected of two, edge reactance component, so that it is determined that
VCO frequency coverage.
Step 503：Calculate VCOn locking upper limiting frequency (output peak frequency) and VCOn+1 locking lower frequency limit (outputs
Minimum frequency) difference, obtain two overlapping frequency ranges of VCO, and the VCO crossover region forms being stored in flash；
Step 504：Whether receive to issue judges calibration frequency in overlapping frequency range after frequency order；
Frequency configuration is issued by IBSC.
Step 505：If specifying one of VCO lockings in overlapping frequency range, this step is again comprising following several
Step：
a：Calculate VCOn locking upper limiting frequency fnMAXWith VCOn+1 locking lower frequency limit fmMIN；
b：Judgment threshold is calculated, such as
c：With the less voltage controlled oscillator VCO n lockings of locking lower frequency limit if calibration frequency is less than judgment threshold；
d：If greater than judgment threshold then with the larger voltage controlled oscillator VCO n+1 lockings of locking upper limiting frequency；
e：The VCO of record calibration locking frequency point numbering.
Step 506：If calibrating frequency not in crossover region, the VCO that can be locked is searched for；
The tuning bandwidth for falling into which VCO by judgement calibration frequency just selects corresponding VCO.
Step 507：Calibration frequency is specified after unique lock VCO, local oscillator letter is provided for the I/Q modulator of wideband transmitter
Number, to residual baseband, using large, medium and small step-length, easily method is adjusted the carrier wave leakage school completed to I/Q modulator
It is accurate；
The gain that carrier wave leakage calibrates the VCO to calibrating locking frequency point is related.
Step 508：Preserve calibration data and complete calibration.
The calibration of wideband transmitter carrier wave leakage can be completed using the flow configuration of the above, and ensured in overlapping region
Frequency is not or not VCO edge, it is ensured that the reliability of emitter work.
Present embodiment also includes the flow for enabling calibration data as shown in fig. 6, step is as follows：
601：It is electric on emitter, software loading and each module initialization；
602：Receive and put after frequency order, VCO crossover regions form in flash is stored in lookup；
603：The VCO specified in flash is called to number if put frequency is in overlapping frequency range；
604：VCO lockings are searched for if put frequency is not in overlapping frequency range；
605：Enable calibration data.
The wideband transmitter carrier wave leakage school that flow solves multiple VCO coverings is calibrated and enabled by above carrier wave leakage
Quasi- Problem of Failure.Give frequency selection in crossover region fixed VCO lockings by optimized algorithm, so not only avoid issuing frequency configuration
Cause phaselocked loop losing lock during environmental change to VCO edges and ensure that the validity and reliability of carrier wave leakage calibration data.
Obviously, those skilled in the art should be understood that above-mentioned each module of the invention, each step can be with general
Computing device realizes that they can be concentrated on single computing device, or be distributed in what multiple computing devices were constituted
On network, alternatively, they can be realized with the executable program code of computing device, it is thus possible to be stored in
Performed in storage device by computing device, either they are fabricated to respectively each integrated circuit modules or by they
Multiple modules or step are fabricated to single integrated circuit module to realize.So, the present invention is not restricted to any specific hard
Part and software are combined.
Embodiments of the invention are the foregoing is only, are not intended to limit the invention, for those skilled in the art
For member, the present invention can have various modifications and variations.Any modification within the spirit and principles of the invention, being made,
Equivalent substitution, improvement etc., should be included in the scope of the protection.
Claims (8)
1. a kind of phaselocked loop, including：Phase discriminator, loop filter and multiple voltage controlled oscillators, wherein, the phase discriminator is to described
Loop filter output signal, the loop filter is selectively believed to one of any output of the multiple voltage controlled oscillator
Number；Also include one group of variable reactive component, a Fractional-N frequency device and a set of division device, each voltage controlled oscillator with described one group
Wide-band tuning is realized in any one connection in variable reactive component, and one end of the Fractional-N frequency device connects the voltage controlled oscillator
Output end, the other end connects the phase discriminator, the set of division device be connected to the output end of the voltage controlled oscillator there is provided
Output signal after frequency dividing.
2. phaselocked loop as claimed in claim 1, it is characterised in that：In the multiple voltage controlled oscillator, adjacent VCO
There is overlaid frequency in desired operating temperature range in device.
3. a kind of wideband transmitter, including：I/Q modulator and phaselocked loop, the phaselocked loop are connected with the I/Q modulator, are institute
State I/Q modulator and local oscillation signal is provided, wherein, the phaselocked loop includes：Phase discriminator, loop filter and multiple voltage controlled oscillators,
Wherein, the phase discriminator is to the loop filter output signal, and the loop filter is selectively to the multiple voltage-controlled
One of any output signal of oscillator；Also include one group of variable reactive component, a Fractional-N frequency device and a set of division device, it is each
Individual voltage controlled oscillator is connected with any one in one group of variable reactive component and realizes wide-band tuning, the Fractional-N frequency device
One end connects the output end of the voltage controlled oscillator, and the other end connects the phase discriminator, and the set of division device is connected to described
There is provided the output signal after frequency dividing for the output end of voltage controlled oscillator.
4. wideband transmitter as claimed in claim 3, it is characterised in that in the multiple voltage controlled oscillator, adjacent voltage-controlled
All there is overlaid frequency in desired operating temperature range in oscillator.
5. a kind of carrier wave leakage calibration method of wideband transmitter using wideband transmitter as claimed in claim 3, including：
The overlapping frequency range of adjacent voltage controlled oscillator in multiple voltage controlled oscillators is calculated, judges calibration frequency whether described heavy
In folded frequency range, if it is, being that the calibration frequency specifies a voltage controlled oscillator from the adjacent voltage controlled oscillator
Locking；
After voltage controlled oscillator locking is specified for the calibration frequency, the I/Q modulator for the wideband transmitter provides local oscillator
Signal, and complete to calibrate the carrier wave leakage of the I/Q modulator by being adjusted residual baseband, and preserve calibration
Data.
6. method as claimed in claim 5, it is characterised in that specify voltage controlled oscillator locking bag for the calibration frequency
Include：
Judgment threshold is calculated according to the locking upper limiting frequency of adjacent voltage controlled oscillator and locking lower frequency limit；
The calibration frequency is compared with the judgment threshold, if the calibration frequency is less than the judgment threshold,
Specify the less voltage controlled oscillator locking of locking lower frequency limit in adjacent voltage controlled oscillator；If the calibration frequency is more than described
Judgment threshold, then specify the larger voltage controlled oscillator locking of locking upper limiting frequency in adjacent voltage controlled oscillator.
7. method as claimed in claim 5, it is characterised in that also include：
Before the overlapping frequency range of adjacent voltage controlled oscillator in calculating multiple voltage controlled oscillators, also need determination the multiple voltage-controlled
The frequency coverage of oscillator；
When the calibration frequency is not in the overlapping frequency range, according to the frequency coverage of the multiple voltage controlled oscillator
Scope specifies voltage controlled oscillator locking for the calibration frequency.
8. method as claimed in claim 6, it is characterised in that also include：
Specified for the calibration frequency after voltage controlled oscillator locking, record the numbering of the voltage controlled oscillator, frequency is put receiving
During order, put frequency is judged whether in the overlapping frequency range, if according to the volume of the voltage controlled oscillator
Number, corresponding voltage controlled oscillator is called, and enable corresponding calibration data.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110181182.3A CN102857221B (en) | 2011-06-30 | 2011-06-30 | The carrier wave leakage calibration method of phaselocked loop, wideband transmitter and wideband transmitter |
| PCT/CN2011/082969 WO2013000239A1 (en) | 2011-06-30 | 2011-11-25 | Phase-locked loop, wideband transmitter and carrier leakage calibration method of wideband transmitter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110181182.3A CN102857221B (en) | 2011-06-30 | 2011-06-30 | The carrier wave leakage calibration method of phaselocked loop, wideband transmitter and wideband transmitter |
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| Publication Number | Publication Date |
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| CN102857221A CN102857221A (en) | 2013-01-02 |
| CN102857221B true CN102857221B (en) | 2017-07-21 |
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| US9154231B2 (en) * | 2013-01-17 | 2015-10-06 | Alcatel Lucent | Generation of an optical local-oscillator signal for a coherent-detection scheme |
| CN109450467B (en) * | 2018-12-28 | 2024-04-05 | 陕西烽火电子股份有限公司 | Device and method for synthesizing radio frequency signal based on IQ modulator interpolation phase-locked loop |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6731712B1 (en) * | 2000-02-04 | 2004-05-04 | Conexant Systems, Inc. | Fully integrated broadband tuner |
| CN1714509A (en) * | 2002-11-22 | 2005-12-28 | 日本电气株式会社 | PLL circuit |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5686864A (en) * | 1995-09-05 | 1997-11-11 | Motorola, Inc. | Method and apparatus for controlling a voltage controlled oscillator tuning range in a frequency synthesizer |
| CN1212738C (en) * | 2002-03-22 | 2005-07-27 | 威盛电子股份有限公司 | Multiple frequency output clock pulse signal synthesizer and its synthesis method |
| JP4067360B2 (en) * | 2002-08-09 | 2008-03-26 | シャープ株式会社 | Inspection apparatus and inspection method |
| JP2005094282A (en) * | 2003-09-17 | 2005-04-07 | Renesas Technology Corp | Semiconductor integrated circuit for communication |
| US7301415B2 (en) * | 2005-12-12 | 2007-11-27 | Airoha Technology Corp. | Automatic frequency tuning in a phase lock loop |
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2011
- 2011-06-30 CN CN201110181182.3A patent/CN102857221B/en active Active
- 2011-11-25 WO PCT/CN2011/082969 patent/WO2013000239A1/en active Application Filing
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6731712B1 (en) * | 2000-02-04 | 2004-05-04 | Conexant Systems, Inc. | Fully integrated broadband tuner |
| CN1714509A (en) * | 2002-11-22 | 2005-12-28 | 日本电气株式会社 | PLL circuit |
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| CN102857221A (en) | 2013-01-02 |
| WO2013000239A1 (en) | 2013-01-03 |
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