CN206115449U - Radio frequency identification forward chaining way - Google Patents
Radio frequency identification forward chaining way Download PDFInfo
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- CN206115449U CN206115449U CN201620883315.XU CN201620883315U CN206115449U CN 206115449 U CN206115449 U CN 206115449U CN 201620883315 U CN201620883315 U CN 201620883315U CN 206115449 U CN206115449 U CN 206115449U
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Abstract
The utility model provides a radio frequency identification forward chaining way, include: transceiver unit for control radio frequency signal or acquisition circuit parameter, quadrature modulator, adjustable attenuator, this transceiver unit carries out the quadrature modulation according to the local oscillator signal to modulating signal and exports radiofrequency signal to this quadrature modulator output I way modulating signal, Q way modulating signal, and the control signal that this transceiver unit was received to this adjustable attenuator carries out the power adjustment to radiofrequency signal, power amplifier unit, coupler, power detection unit, this power amplifier unit is connected to the input of this coupler, and the output of this coupler radiates away radiofrequency signal through antenna element, and this power detection unit's first input end is connected to the coupling end of this coupler, this transceiver unit connects this power detection unit in order to obtain the transmit power value to the adjustment control signal give this quadrature modulator and adjustable attenuator. The utility model discloses a forward chaining way emissivity can be more stable, and inside circuit reliability is high.
Description
Technical field
The utility model is related to technical field of RFID, more particularly to a kind of RF identification forward link.
Background technology
Super high frequency radio frequency technology of identification is a kind of remote non contact angle measurement technology, and radio-frequency identification reader/writer is by transmitting-receiving
Radiofrequency signal is written and read to remote radio frequency recognizing electronic label, the fields such as Internet of Things is widely used in, especially in intelligence
Energy field of traffic, to vehicle management etc. very big effect is played.The forward link of radio-frequency identification reader/writer mainly includes association of eating dishes without rice or wine
In view with regard to radio-frequency identification reader/writer the radio frequency parameter such as coded system, modulation system, set of frequency, power configuration realization.
The implementation of current super high frequency radio frequency recognition read-write machine mainly includes using integrated chip and adopts discrete device
To realize.Wherein, the size of radio-frequency identification reader/writer can be reduced by the way of integrated chip, but is limited to integrated chip certainly
The performance of body, its configuration mode also underaction is difficult to realize high performance radio-frequency identification reader/writer；And adopt discrete device side
The radio-frequency identification reader/writer of formula, often internal circuit configuration is relatively simple, can only realize simple radio frequency recognition function, it is impossible to protect
The uniformity of radio-frequency identification reader/writer performance under card complex environment.
Utility model content
The purpose of this utility model is to provide a kind of RF identification forward link, solves RF identification in prior art
Read write line emitting performance is not good, the easy protected from environmental, technical problem that internal circuit reliability is not high.
In order to solve above-mentioned technical problem, a kind of RF identification forward link of the present utility model, including：
Base Band Unit, for controlling radiofrequency signal or Acquisition Circuit parameter；
Connect quadrature modulator, the adjustable attenuator of the Base Band Unit, the Base Band Unit is to the quadrature modulator
Output I roads modulated signal, Q roads modulated signal, the quadrature modulator carries out orthogonal modulation according to local oscillation signal to modulated signal
Output radiofrequency signal, the adjustable attenuator receives the control signal of the Base Band Unit and carries out power adjustment to radiofrequency signal；
Connect the power amplifier unit of the adjustable attenuator, for amplifying the power of radiofrequency signal；
Coupler, power detecting unit, the input of the coupler connects the power amplifier unit, the coupler it is defeated
Go out end to radiate radiofrequency signal by antenna element, the of the coupled end of the coupler connection power detecting unit
One input；
The Base Band Unit connects the power detecting unit to obtain transmission power level, and adjusts control signal to described
Quadrature modulator and adjustable attenuator.
Used as the further improvement of the above-mentioned RF identification forward link of the utility model, the coupler includes being parallel to each other
The first quarter-wave microstrip line and the second quarter-wave microstrip line, the first quarter-wave microstrip line
One end connects the power amplifier unit, and the other end of the first quarter-wave microstrip line passes through the antenna element by radio frequency
Signal radiate, and one end of the second quarter-wave microstrip line connects the first input of the power detecting unit
End.
As the further improvement of the above-mentioned RF identification forward link of the utility model, the antenna element include antenna and
Connect the front network of the antenna, the antenna introduces the radiofrequency signal of forward link by the front network.
Used as the further improvement of the above-mentioned RF identification forward link of the utility model, the RF identification forward link is also
Including the circulator being connected between the coupler and the antenna element, the first end of the circulator connects the coupling
The output end of device, the second end of the circulator connects the antenna element, power described in the three-terminal link of the circulator
Second input of detector unit.
Used as the further improvement of the above-mentioned RF identification forward link of the utility model, the adjustable attenuator can for numeral
Controlled attenuator, the Base Band Unit to the adjustable attenuator provides control signal.
Used as the further improvement of the above-mentioned RF identification forward link of the utility model, the power amplifier unit is put including driving
The power amplifier of big device and the connection driving amplifier.
As the further improvement of the above-mentioned RF identification forward link of the utility model, the driving amplifier and the work(
Temperature compensation attenuator is provided between rate amplifier.
Used as the further improvement of the above-mentioned RF identification forward link of the utility model, the Base Band Unit includes processor
And the analog-digital converter of the connection processor, the processor is by analog-digital converter acquisition transmission power level.
Used as the further improvement of the above-mentioned RF identification forward link of the utility model, the Base Band Unit also includes connection
The digital to analog converter of the processor, the digital to analog converter receives the data signal of the processor and is converted into corresponding I
Road modulated signal, Q roads modulated signal.
Used as the further improvement of the above-mentioned RF identification forward link of the utility model, the power detecting unit is logarithm
Wave detector.
Compared with prior art, the utility model is by including designs such as coupler, power detecting unit, Base Band Unit
Feedback circuit detects transmission power, and realizes fine tuning in combination with coarse adjustment, with reality with the cooperation of quadrature modulator, adjustable attenuator
The precise control and timing alignment of existing emitting performance.Forward link emitting performance of the present utility model is more stable, and electricity is realized in inside
Road reliability is high.
After the detailed description of the utility model embodiment is read in conjunction with the accompanying, other features of the present utility model and advantage
Will become clearer from.
Description of the drawings
In order to be illustrated more clearly that the technical scheme of the utility model embodiment or prior art, below will be to embodiment party
The accompanying drawing to be used needed for formula or description of the prior art is briefly described, it is therefore apparent that drawings in the following description are only
It is some embodiments described in the utility model, for those of ordinary skill in the art, is not paying creative labor
On the premise of dynamic, can be with according to these other accompanying drawings of accompanying drawings acquisition.
Fig. 1 is RF identification forward link schematic diagram in the embodiment of the utility model one.
Specific embodiment
The utility model is described in detail below with reference to each embodiment shown in the drawings.But these embodiments
The utility model is not intended to limit, structure, method or work(that one of ordinary skill in the art is made according to these embodiments
Conversion on energy is all contained in protection domain of the present utility model.
It should be noted that in various embodiments, may be using identical label or mark, but these not generations
Absolute contact relation in table structure or function.Also, " first ", " second ", " the 3rd " being previously mentioned in each embodiment
Not representative structure or absolute differentiation relation functionally, these are merely for convenience of description.
As shown in figure 1, RF identification forward link schematic diagram in the embodiment of the utility model one.RF identification forward chaining
Road include Base Band Unit 10, quadrature modulator 20, adjustable attenuator 30, power amplifier unit 40, coupler 50, logarithmic detector 60,
Circulator 70, antenna element 80.Antenna element 80 is used for transceiving radio frequency signal, and antenna element 80 is from forward direction link definition standard
It is different, it is also possible to not included in the module in RF identification forward link, belonged to outside RF identification forward link.Specifically
Ground, antenna element 80 includes front network 81 and antenna 82, and front network 81 is used for as antenna 82 and RF identification forward link
Between path is provided, antenna 82 introduces the radiofrequency signal of forward link by front network 81.Front network 81 can include using
In the device of transceiver insulation, including the device of day line options etc..Antenna 82 is a kind of converter, and it leads transmission above-the-line promotion
Traveling wave, is transformed in unbounded medium（Typically free space）The electromagnetic wave of middle propagation, or contrary conversion is carried out, antenna 82
It is for the device of direct transceiving radio frequency signal.Base Band Unit 10 is used to control radiofrequency signal or Acquisition Circuit parameter, base band list
Control circuit, the control signal specified by control circuit output can be included inside unit 10.
Quadrature modulator 20, in the present embodiment, realizes, quadrature modulator 20 connects using the framework of directly modulation
Base Band Unit 10, from Base Band Unit 10 to quadrature modulator 20 I roads modulated signal, Q roads modulated signal, quadrature modulator 20 are provided
Local oscillation signal is also received, it is preferable that quadrature modulator 20 connects the phase-locked loop frequency integrator of inside, by internal phaselocked loop
Frequency synthesizer provides local oscillation signal.Quadrature modulator 20 will receive I road modulated signals and Q roads modulated signal is loaded onto carrier wave,
Orthogonal modulation is carried out to modulated signal according to local oscillation signal, quadrature modulator 20 is penetrated after orthogonal modulation from output end output
Frequency signal, that is, need the radiofrequency signal radiateing by antenna element 80.Because entering to radio frequency recognizing electronic label at a distance
Row identification, so have certain requirement to the transmission power of radiofrequency signal, so also needing to by other circuits to radiofrequency signal
Processed.In the present embodiment, I roads modulated signal, the Q roads modulated signal that Base Band Unit 10 is provided is used as modulated signal package
Information containing data communication, also comprising the amplitude power that can adjust modulating wave.By adjusting I roads modulated signal, Q roads modulation letter
Number can realize the fine tuning of modulating wave power output.
Adjustable attenuator 30 connects quadrature modulator 20 to receive the radiofrequency signal of the output of quadrature modulator 20, is also connected with base
The control signal that tape cell 10 is adjusted with receiving attenuation amount.Adjustable attenuator 30 is according to the control signal of Base Band Unit 10 to radio frequency
Signal carries out power adjustment.Preferably, adjustable attenuator 30 is digital adjustable attenuator, you can include some sections in controlled attenuator
Attenuation module, attenuation module has several on-off circuits according to actually there is different pad values between attenuation module, by switch
The closing of circuit turn on any combination in several attenuation modules to realize the size of differential declines amount, and on-off circuit is closed
Performed by receiving control signal.Therefore, by Base Band Unit 10 control signal is provided to adjustable attenuator 30 to realize to defeated
Go out the adjustment of power.Adjustable attenuator can be specifically 6 digit control adjustable step attenuators, and the minimum of adjustable attenuator is controlled
Not only up to 0.5dB, the accurate step by step modulating of power output is capable of achieving, radiofrequency signal Jing adjustable attenuator is capable of achieving amplitude range
The change of about 31.5dB.
The power amplifier unit 40 of connection adjustable attenuator 30 is used to amplify the power of radiofrequency signal, it is preferable that power amplifier unit 40
Including driving amplifier 41 and power amplifier 43, power amplifier 43 connects driving amplifier 41 and amplifies as the second level, drives
Dynamic amplifier 41 inputs to power amplifier 43 after then is amplified signal, final Jing power amplifiers 43 form high-power output letter
Number launch eventually through coupler 50, antenna element 80 etc..Driving amplifier 41, i.e. driving stage amplifier, by itself
Gain so that overall power can export enough power with driving power amplifier 43.Power amplifier 43 is final amplifier,
There is provided the peak power output configured needed for radio-frequency identification reader/writer.In RF identification forward link in present embodiment,
The linear circuit of HDR is formed by adjustable attenuator 30 and driving amplifier 41, additionally, power amplifier 43 also fills
Divide and make use of this design of Reducing Rating, it can be ensured that forward link has the sufficiently high linearity, prevent the radiofrequency signal launched non-
Linear zone produces the phenomenon such as deformation or intermodulation.
In addition, radio-frequency identification reader/writer is typically all arranged out of doors, the change of external environment condition is easy to affect radio frequency to know
The radiofrequency signal of forward link in other read write line, and radio-frequency identification reader/writer is after starting up, and internal temperature also can be sent out
The very big change of life, often this impact can cause the change of power output very big.In a preferred embodiment, in order to eliminate
This impact, arranges temperature compensation attenuator 42, the decay of temperature compensation attenuator 42 between driving amplifier 41 and power amplifier 43
Value it is linear with temperature change, can under temperature variations effective correcting circuit entire gain.Specifically, temperature is worked as
When degree rises, the decay of amplifying device gain reduction and temperature compensation attenuator also diminishes；Conversely, upon a drop in temperature, amplifying device
The decay of gain increase and temperature compensation attenuator also becomes therewith big.Environment can be effectively reduced using the environmental characteristics of temperature compensation attenuator
Impact of the temperature to the power output of RF identification forward link in radio-frequency identification reader/writer so that power output is maintained at one
Relatively steady state.
Coupler 50 is mainly used in coupling the radiofrequency signal launched all the way as power detection.The input of coupler 50 connects
Power amplifier unit 40 is connect, the output end of coupler 50 is radiate radiofrequency signal by antenna element 80, the coupling of coupler 50
End connection logarithmic detector 60, logarithmic detector 60 obtains radiofrequency signal by coupling.In order to cost-effective, coupler 50 is preferred
Ground is strip line coupler, including two quarter-wave microstrip lines, the first quarter-wave being respectively parallel to each other
Microstrip line and the second quarter-wave microstrip line, one end of the first quarter-wave microstrip line connects power amplifier as input
Unit 40, the other end of the first quarter-wave microstrip line connects antenna element 80 as output end, in more embodiment party
In formula, circulator 70 is connected between the other end of the quarter-wave microstrip line of antenna element 80 and first, below will be detailed
State, i.e. the other end of the first quarter-wave microstrip line is radiate radiofrequency signal by antenna element 80.Two or four point
One of wave microstrip line one end as coupled end connect logarithmic detector 60, to logarithmic detector 60 provide radiofrequency signal.Need
It is noted that the embodiment of coupler 50 is not described as limit with above-mentioned, however not excluded that can using directional coupler etc. its
He replaces power coupling circuit.
Logarithmic detector 60, is the preferred embodiment of power detecting unit, and the radiofrequency signal that will be coupled into switchs to voltage
Parameter, i.e., carry out magnitude demodulator to radiofrequency signal, and the amplitude information of radiofrequency signal is linearly changed into into voltage signal.Logarithm is examined
The first output end connection Base Band Unit 10 of ripple device 60, the first output end output first input end input of logarithmic detector 60
The voltage signal that radiofrequency signal is converted into obtains transmission power level, base to Base Band Unit 10, Base Band Unit 10 by voltage signal
Tape cell 10 adjusts quadrature modulator 20 and adjustable attenuator 30 according to transmission power level, i.e., the control letter after output adjustment
Number to quadrature modulator 20 and adjustable attenuator 30.For example, transmission power level is not up to designated value, just increases quadrature modulator 20
Power output or reduce adjustable attenuator 30 decay.
In the present embodiment, Base Band Unit 10 includes processor 11 and analog-digital converter 13（ADC, Analog-to-
Digital Converter）, the input of analog-digital converter 13 receives the voltage signal of the output of logarithmic detector 60, by interior
Portion processes and is converted into data signal, and from the output end connection processor 11 of analog-digital converter 13 transmission power level is provided it.Place
Reason device 11 is by connecting digital to analog converter 12（DAC, Digital-to-Analog Converter）Input output control letter
Number, the output end connection quadrature modulator 20 of digital to analog converter 12, the digital command that digital to analog converter 12 generates processor 11
Be converted to modulated signal, the i.e. data signal of the receiving processor 11 of digital to analog converter 12 and be converted into corresponding I roads modulated signal,
Q roads modulated signal.
In a preferred embodiment, circulator 70, circulator 70 are additionally provided between coupler 50 and antenna element 80
First end 71 connect the output end of coupler 50, the connection of the second end 72 antenna element 80 of circulator 70, the of circulator 70
Three end 73 connects the second input of logarithmic detector 60, and in the present embodiment, logarithmic detector 60 is dual input logarithm
Wave detector.The acting as of circulator 70 can protect power amplifier not breakdown under the no-load condition of antenna element 80, in addition
The echo-signal of antenna 82 can also be extracted is used for the detection of antenna condition.Preferably, the 3rd end 73 of circulator 70 with it is right
Coupler 91 is provided between number wave detector 60, for preventing logarithmic detector 60 from crossing high energy by what antenna element 80 was reflected
Amount is damaged.Specifically, the input of coupler 91 connects the 3rd end 73 of circulator 70, and the output end of coupler 91 is connected with negative
92 are carried, the coupled end of coupler 91 connects the second input of logarithmic detector 60.Coupler 90 can be specifically microstrip line,
One end of microstrip line connects the 3rd end 73 of circulator 70, and the other end connection of microstrip line loads 92, and parallel connection on the microstrip line sets
It is equipped with the second input that coupling resistance connects logarithmic detector 60.It should be noted that the embodiment of coupler 91 is not
It is described as limit with above-mentioned, however not excluded that other power couplings such as the embodiment of directional coupler or above-mentioned parallel microstrip line can be used
Close circuitry instead.
Because three port direction characteristics of circulator 70 itself, when the first end 71 of circulator 70 is input, the
Two ends 72 are output end, and the 3rd end 73 is isolation end, the first end of the signal of the output end output of coupler 50 from circulator 70
71 the second ends 72 for flowing to circulator 70, are transmitted further to antenna element 80, without being received by logarithmic detector 60.Work as annular
When second end 72 of device 70 is input, the 3rd end 73 of circulator 70 is output end, and the first end 71 of circulator 70 is isolation
End, therefore the echo-signal of antenna 82 flows to the 3rd end 73 of circulator 70 by the second end 72 of circulator 70, will not transmit
To power amplifier 43, also because of zero load the signal for reflecting will not be caused to burn out power amplifier 43.Circulator 70 sets
Putting can reduce the reflection of high-power signal under no-load condition, be prevented effectively under power amplifier mismatch Conditions and hit caused by possibility
Wear phenomenon so that the security and reliability of circuit is greatly promoted.
As described above, by detecting to antenna echo power with the cooperation of circulator 70.Antenna 82 return
Ripple signal can be exported to logarithmic detector 60 by the 3rd end 73 of circulator 70, and logarithmic detector 60 is by the echo of antenna 82
The amplitude information of signal is linearly changed into voltage signal and is supplied to analog-digital converter 13 to be conveyed to processor 11 after sampling, and locates
Reason device 11 can pass through the echo of the data calculating antenna for receiving.
In sum, the utility model is by including the feedback circuit of the designs such as coupler, logarithmic detector, Base Band Unit
Detection transmission power, and with the cooperation of quadrature modulator, adjustable attenuator fine tuning is realized in combination with coarse adjustment, to realize emissivity
The precise control and timing alignment of energy.Forward link emitting performance of the present utility model is more stable, and circuit reliability is realized in inside
It is high.
It should be understood that, although this specification is been described by according to embodiment, but not each embodiment only includes one
Individual independent technical scheme, this narrating mode of specification is only that for clarity those skilled in the art will should say
Bright book as an entirety, the technical scheme in each embodiment can also Jing it is appropriately combined, forming those skilled in the art can
With the other embodiment for understanding.
Those listed above is a series of to describe the tool for being only for feasibility embodiment of the present utility model in detail
Body illustrates that they are simultaneously not used to limit protection domain of the present utility model, all to be made without departing from the utility model skill spirit
Equivalent implementations or change should be included within protection domain of the present utility model.
Claims (10)
1. a kind of RF identification forward link, it is characterised in that include：
Base Band Unit, for controlling radiofrequency signal or Acquisition Circuit parameter；
Connect quadrature modulator, the adjustable attenuator of the Base Band Unit, the Base Band Unit to the quadrature modulator exports I
Road modulated signal, Q roads modulated signal, the quadrature modulator carries out orthogonal modulation output to modulated signal and penetrates according to local oscillation signal
Frequency signal, the adjustable attenuator receives the control signal of the Base Band Unit and carries out power adjustment to radiofrequency signal；
Connect the power amplifier unit of the adjustable attenuator, for amplifying the power of radiofrequency signal；
Coupler, power detecting unit, the input of the coupler connects the power amplifier unit, the output end of the coupler
Radiofrequency signal is radiate by antenna element, the first of the coupled end connection power detecting unit of the coupler is defeated
Enter end；
The Base Band Unit connects the power detecting unit to obtain transmission power level, and adjusts control signal to described orthogonal
Modulator and adjustable attenuator.
2. RF identification forward link according to claim 1, it is characterised in that the coupler includes what is be parallel to each other
First quarter-wave microstrip line and the second quarter-wave microstrip line, the one of the first quarter-wave microstrip line
The end connection power amplifier unit, the other end of the first quarter-wave microstrip line is believed radio frequency by the antenna element
Number it radiate, one end of the second quarter-wave microstrip line connects the first input end of the power detecting unit.
3. RF identification forward link according to claim 1, it is characterised in that the antenna element includes antenna and company
The front network of the antenna is connect, the antenna introduces the radiofrequency signal of forward link by the front network.
4. RF identification forward link according to claim 1, it is characterised in that the RF identification forward link is also wrapped
The circulator being connected between the coupler and the antenna element is included, the first end of the circulator connects the coupler
Output end, the second end of the circulator connects the antenna element, power inspection described in the three-terminal link of the circulator
Survey the second input of unit.
5. RF identification forward link according to claim 1, it is characterised in that the adjustable attenuator is adjustable for numeral
Attenuator, the Base Band Unit to the adjustable attenuator provides control signal.
6. RF identification forward link according to claim 1, it is characterised in that the power amplifier unit includes drive amplification
The power amplifier of device and the connection driving amplifier.
7. RF identification forward link according to claim 6, it is characterised in that the driving amplifier and the power
Temperature compensation attenuator is provided between amplifier.
8. RF identification forward link according to claim 1, it is characterised in that the Base Band Unit include processor and
Connect the analog-digital converter of the processor, the processor obtains transmission power level by the analog-digital converter.
9. RF identification forward link according to claim 8, it is characterised in that the Base Band Unit also includes connection institute
The digital to analog converter of processor is stated, the digital to analog converter receives the data signal of the processor and is converted into corresponding I roads
Modulated signal, Q roads modulated signal.
10. RF identification forward link according to claim 1, it is characterised in that the power detecting unit is logarithm
Wave detector.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620883315.XU CN206115449U (en) | 2016-08-16 | 2016-08-16 | Radio frequency identification forward chaining way |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620883315.XU CN206115449U (en) | 2016-08-16 | 2016-08-16 | Radio frequency identification forward chaining way |
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| Publication Number | Publication Date |
|---|---|
| CN206115449U true CN206115449U (en) | 2017-04-19 |
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ID=58512587
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201620883315.XU Active CN206115449U (en) | 2016-08-16 | 2016-08-16 | Radio frequency identification forward chaining way |
Country Status (1)
| Country | Link |
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| CN (1) | CN206115449U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2018191985A1 (en) * | 2017-04-21 | 2018-10-25 | 深圳市大疆创新科技有限公司 | Radio frequency control system and control method |
| CN109217902A (en) * | 2017-06-29 | 2019-01-15 | 深圳市金溢科技股份有限公司 | Radio frequency attenuator control method, control device and reader based on temperature-compensating |
-
2016
- 2016-08-16 CN CN201620883315.XU patent/CN206115449U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2018191985A1 (en) * | 2017-04-21 | 2018-10-25 | 深圳市大疆创新科技有限公司 | Radio frequency control system and control method |
| CN109217902A (en) * | 2017-06-29 | 2019-01-15 | 深圳市金溢科技股份有限公司 | Radio frequency attenuator control method, control device and reader based on temperature-compensating |
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