CN208421836U - Super high frequency radio frequency identification label signal demodulating equipment - Google Patents
Super high frequency radio frequency identification label signal demodulating equipment Download PDFInfo
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Abstract
The utility model discloses a kind of ultrahigh frequency RFID label signal demodulator circuit devices, including detection mechanism, the demodulating mechanism with multi signal access, comparator and processor；Current state of the processor according to read-write equipment, control demodulating mechanism gating current demand signal access corresponding with current state；The two-way obtained according to label return signal signal to be demodulated is sent to demodulating mechanism by detection mechanism；By demodulating mechanism under current demand signal access gating condition, two-way processing signal is obtained to two-way signal to be demodulated and gives comparator；The obtained corresponding demodulated signal of label return signal after being compared to two-way processing signal is sent to processor by comparator.Realize rectified signal full dynamic range, being all-trans completely demodulates to speed range, avoid the occurrence of the high state for being difficult to demodulating and decoding when returning bit rate, avoid after carrying out AD acquisition, the algorithm for carrying out large amount of complex could be completed to demodulate to label return signal.
Description
Technical field
The utility model relates to Signal Regulation technical fields, and in particular to a kind of super high frequency radio frequency identification (Radio
Frequency Identification, RFID) label signal demodulating equipment.
Background technique
The core component of ultrahigh frequency RFID read-write equipment system is ultrahigh frequency RFID electronic tag and electronic tag
Read-write equipment.Read-write equipment emits the radio wave electron label of specific frequency, to drive electronic tag circuit will be internal
Data send out, while received in sequence and demodulating label data, thus obtain the data stored in electronic tag.
Currently, mostly using the method pair of RF envelope detection greatly after RFID read-write equipment receives the signal that label returns
Signal is demodulated, but it needs to face following problems:
1) since the forward emitting power floating range of RFID read-write equipment is larger, and usually transmission power is very big, to subtract
The influence that small carrier wave handles follow-up signal will generally carry out carrier wave elimination, and carrier wave eliminates result by load condition, antenna
It is influenced with degree etc., when transmission power is very big, carrier cancellation circuit effect is limited, can not be by detection width under all transmission powers
Degree is limited in the range of a very little, therefore the dynamic range of signals after detection is larger.
2) when the processing such as being filtered, amplify to signal after detection, processing circuit response time, the distortion factor will necessarily be introduced
Etc. influence factors, signal biggish for dynamic range, under different conditions, influence degree is different: since RFID read-write equipment is adopted
With half-duplex operating mode, when the response time of circuit be greater than the returning the code waiting time of read-write equipment signal (return the code waiting time:
That is signaling signal and the time interval for returning code signal, reverse rate is bigger, and it is shorter to return the code waiting time), signaling signal processing is dynamic
It does not complete, the waveform of subsequent time code signal will be had an impact, detected amplitude is bigger, then influences more serious, in fact it could happen that hair
Code signal falls into oblivion back the state of code signal completely.When RFID read-write equipment reversely returns bit rate difference, signal distortion is different.
3) read-write equipment that signal demodulation is carried out using RF envelope detection, after the completion of demodulator circuit signal processing, due to
Input signal difference, output waveform differ greatly, and need to carry out AD acquisition mostly, and design largely again on signal processing software
Miscellaneous algorithm could be completed to decode, decoding software difficulty is significantly increased to label signal, inevitable also to occupy a large amount of processor
Resource increases processor cost.And the circuit without AD acquisition, it is more difficult for the decoding process of signal, easily occur
The state of certain frequency band signals can only be demodulated.But since dynamic range of signals is larger, for part signal, demodulation process is not perfect,
It cannot complete to decode by software algorithm, the reverse signal of high-speed occur, decode more difficult phenomenon, can be greatly reduced
Read-write equipment performance.
Therefore, make it to RFID read-write equipment full dynamic range, the return signal being all-trans into speed range processing output
Waveform has high consistency, to improve the accuracy of read-write equipment reverse link signal demodulation, demodulator circuit adaptability, signal
Processing result output amplitude is constant, waveform stabilization, reach can be sent directly into processor I/O interface processing, need not move through into
Row AD acquisition.It is undesirable to solve demodulation result when high time bit rate, it is difficult to the problem of decoding, while output signal is convenient for subsequent place
Device decoding is managed, without complicated data processing algorithm, the reduction decoding software difficulty of high degree reduces processor cost, is
Those skilled in the art's technical problem urgently to be resolved.
Utility model content
For problem present in customer service the relevant technologies at least to some extent, the purpose of this utility model is to provide one kind
Super high frequency radio frequency identification label signal demodulating circuit device,
To achieve the above object, the utility model provides a kind of ultrahigh frequency RFID label signal demodulator circuit device, including
Detection mechanism, the demodulating mechanism with multi signal access, comparator and processor；
The detection mechanism, the demodulating mechanism, the comparator and the processor are sequentially connected；
The demodulating mechanism is also connected with the processor；
The processor controls the demodulating mechanism gating and the current state pair according to the current state of read-write equipment
The current demand signal access answered；
The first signal to be demodulated obtained according to label return signal and the second signal to be demodulated are sent out by the detection mechanism
Give the demodulating mechanism；
The demodulating mechanism is used under the current demand signal access gating condition, is carried out to the described first signal to be demodulated
The the first processing signal obtained after processing, and, the second processing letter obtained after handling the described second signal to be demodulated
Number, and the first processing signal and the second processing signal are sent to the comparator；
The comparator by it is described first processing signal and second processing signal be compared after the obtained mark
The corresponding demodulated signal of label return signal is sent to the processor.
Further, in ultrahigh-frequency tag signal demodulating equipment described above, the demodulating mechanism is by multistage successively phase
Sub- regulating mechanism even is formed；
Every grade of sub- regulating mechanism includes filter circuit and the amplifying circuit that is connected with the filter circuit；
Next stage amplifying circuit is also connected with upper level filter circuit；
Each filter circuit is connected with the processor；
Final stage amplifying circuit in final stage grade subsolution regulating mechanism is also connected with the comparator；
The filter circuit includes a plurality of signal path.
Further, in ultrahigh-frequency tag signal demodulating equipment described above, the amplifying circuit includes two-way operation
Amplifying circuit or calculus of differences amplifying circuit.
Further, in ultrahigh-frequency tag signal demodulating equipment described above, putting in every grade of sub- regulating mechanism
Big circuit is realized using identical tertiary circuit structure.
Further, in ultrahigh-frequency tag signal demodulating equipment described above, putting in every grade of sub- regulating mechanism
Big circuit is realized using the 4th different circuit structures.
Further, in ultrahigh-frequency tag signal demodulating equipment described above, every signal paths are using identical the
One circuit structure is realized；
Each first circuit structure is corresponding with different circuit configuration parameters.
Further, in ultrahigh-frequency tag signal demodulating equipment described above, first circuit structure is using RC electricity
It realizes on road.
Further, in ultrahigh-frequency tag signal demodulating equipment described above, every signal paths are using different the
Two circuit structures are realized.
Further, in ultrahigh-frequency tag signal demodulating equipment described above, the detection mechanism passes through to the mark
Two geophone intervals of return signal are signed from wavelength control is carried out, make the described first signal to be demodulated and second letter to be demodulated
Number opposite in phase.
Further, in ultrahigh-frequency tag signal demodulating equipment described above, the phase of first signal to be demodulated
Phase difference with the second signal to be demodulated is 180 °.
The ultrahigh frequency RFID label signal demodulating equipment of the utility model, by processor according to the current shape of read-write equipment
State, control demodulating mechanism gates current demand signal access corresponding with current state, so that regulating mechanism is in current demand signal access item
Under part, at the first signal to be demodulated and the second signal to be demodulated that are obtained to detection mechanism according to current label return signal
Reason obtains the first processing signal and second processing signal, then is carried out by comparator to the first processing signal and second processing signal
After obtain the corresponding demodulated signal of current label return signal it is complete to realize rectified signal so that processor is acquired
Dynamic range, being all-trans completely demodulates to speed range, avoids the occurrence of the high state that demodulating and decoding is difficult to when returning bit rate, avoid into
After row AD acquisition, the algorithm for carrying out large amount of complex could be completed to demodulate to label return signal.
Detailed description of the invention
Fig. 1 is the structural schematic diagram of the ultrahigh frequency RFID label signal demodulating equipment embodiment one of the utility model；
Fig. 2 is the structural schematic diagram of the utility model ultrahigh frequency RFID label signal demodulating equipment embodiment two；
Fig. 3 is the circuit diagram of Fig. 2.
Specific embodiment
It is specific below in conjunction with the utility model to keep the purpose of this utility model, technical solution and advantage clearer
The present embodiment technical solution is clearly and completely described in embodiment and corresponding attached drawing.Obviously, described embodiment is only
It is the present embodiment a part of the embodiment, instead of all the embodiments.Based on the embodiments of the present invention, this field is common
Technical staff's every other embodiment obtained without making creative work belongs to the present embodiment protection
Range.
Specification and claims and the (if present)s such as term " first " in above-mentioned attached drawing, " second " are for area
Not similar part, without being used to describe a particular order or precedence order.It should be understood that the data used in this way are appropriate
In the case of can be interchanged, so that embodiments herein described herein can be real with the sequence other than illustrating herein
It applies.
The following examples illustrate the utility model, but is not intended to limit the scope of the present invention.
Embodiment 1
Fig. 1 is the structural schematic diagram of the ultrahigh frequency RFID label signal demodulating equipment embodiment one of the utility model, such as Fig. 1
Shown, the ultrahigh frequency RFID label signal demodulating equipment of the present embodiment may include detection mechanism 10, with multi signal access
Demodulating mechanism 11, processor 12 and comparator 13.Wherein, detection mechanism 10, demodulating mechanism 11, comparator 13 and processor 12
It is sequentially connected；Demodulating mechanism 11 is also connected with processor 12.
During a specific implementation, when read-write equipment emits the radio wave electron label of specific frequency, processing
Device 12 can know the current state of read-write equipment, such as specific frequency, time code waiting time of read-write equipment transmitting in real time.This
Sample, after ultrahigh frequency RFID electronic tag generates current label return signal, processor 12 can be according to the current of read-write equipment
State, control demodulating mechanism 11 gate current demand signal access corresponding with current state.It can be first with 10 pairs of marks of detection mechanism
Label return signal is handled, and obtains the first signal to be demodulated and the second signal to be demodulated, and by the first signal to be demodulated and the
Two signals to be demodulated are sent to demodulating mechanism 11, by demodulating mechanism 11 under current demand signal access gating condition, to first wait solve
The the first processing signal obtained after adjusting signal to be handled, and, second obtained after handling the second signal to be demodulated
Signal is handled, and the first processing signal and second processing signal are sent to comparator 13.
In the present embodiment, can according to the dynamic range of the signal obtained after detection, reversely return the features such as code signal rate,
In conjunction with the major influence factors during demodulated signal, a plurality of signal path of circuit design is set for demodulating mechanism 11, it is different
The signal obtained after the corresponding detection of signal path is different.For example, every signal paths use identical first circuit knot
Structure realizes that each first circuit structure is corresponding with different circuit configuration parameters, and such as the first circuit structure is realized using RC circuit.
Alternatively, the second circuit knot multiple and different according to parameter designings such as the frequencies, floating range, waiting time of label return signal
Structure, so that every signal paths are realized using different second circuit structures.Therefore the circuit characteristic of each signal paths is different,
Carry out differentiation processing to each condition input signals, achievees the purpose that the high consistency of signal output waveform.In this way, demodulating mechanism
11 under current demand signal access gating condition, the first processing signal obtained after handling the first signal to be demodulated, and,
It when the second processing signal obtained after handling the second signal to be demodulated, is influenced smaller, is kept away by dynamic range of signals
Exempt from the movement of signaling signal processing not completing, the waveform of subsequent time code signal will be had an impact, it is complete to avoid the occurrence of signaling signal
The state of code signal is fallen into oblivion back, the distortion factor of the first processing signal and second processing signal is reduced, to realize that rectified signal is complete
Dynamic range, being all-trans completely demodulates to speed range, and the state of demodulating and decoding is difficult to when avoiding the occurrence of high time bit rate.
Demodulating mechanism 11 is by the first processing signal and after second processing signal is sent to comparator 13, by comparator 13 to the
One processing signal and second processing signal are compared, to restore the label return signal of constant amplitude, and the amplitude is permanent
The waveform of fixed label return signal is not varied widely with reasons such as dynamic ranges, at this point it is possible to which amplitude is consolidated
Fixed label return signal is sent to processor as the corresponding demodulated signal of current label return signal, and by the demodulated signal
12 I/O interface, is directly acquired demodulated signal by processor 12, without carrying out AD acquisition.
The ultrahigh frequency RFID label signal demodulating equipment of the present embodiment, by processor 12 according to the current shape of read-write equipment
State, control demodulating mechanism 11 gates current demand signal access corresponding with current state, so that demodulating mechanism 11 is logical in current demand signal
Under the conditions of road, the first signal to be demodulated and the second signal to be demodulated that detection mechanism 10 is obtained according to current label return signal
It is handled, obtains the first processing signal and second processing signal, then by comparator 13 to the first processing signal and second processing
Signal obtains the corresponding demodulated signal of current label return signal after being compared, so that processor 12 is acquired, realize
Rectified signal full dynamic range, being all-trans completely demodulates to speed range, is difficult to demodulating and decoding when avoiding the occurrence of high time bit rate
State avoids after carrying out AD acquisition, and the algorithm for carrying out large amount of complex could be completed to demodulate to label return signal.
Fig. 2 is the structural schematic diagram of the utility model ultrahigh frequency RFID label signal demodulating equipment embodiment two, such as Fig. 2 institute
Show, on the basis of the ultrahigh frequency RFID label signal demodulating equipment embodiment shown in Fig. 1 of the present embodiment, further in further detail
The technical solution of the utility model is described in ground.
As shown in Fig. 2, demodulating mechanism 11 is formed by the subsolution regulating mechanism 111 that multistage is sequentially connected in the present embodiment；Every grade
Subsolution regulating mechanism 111 includes filter circuit 1111 and the amplifying circuit 1112 being connected with filter circuit 1111；The amplification of next stage
Circuit 1112 is also connected with the filter circuit of upper level 1111；Each filter circuit 1111 is connected with processor 12；Final stage grade
Final stage amplifying circuit in demodulating mechanism 111 is also connected with comparator 13；Filter circuit 1111 includes a plurality of signal path.Its
In, the amplifying circuit 1112 in every grade of subsolution regulating mechanism 111 is realized using identical tertiary circuit structure, alternatively, every grade of subsolution
Amplifying circuit 1112 in regulating mechanism 111 is realized using the 4th different circuit structures.
As shown in Fig. 2, the present embodiment retouches the technical solution of the utility model by taking two-stage subsolution regulating mechanism 111 as an example
It states, in practical applications, the number of subsolution regulating mechanism 111 can be set according to actual needs.Detection mechanism 10 is by label
Two geophone intervals of return signal make the phase phase of the first signal to be demodulated and the second signal to be demodulated from wavelength control is carried out
Instead.For example, the phase difference of the phase of the first signal to be demodulated and the second signal to be demodulated is 180 °.The filter circuit of the first order
1111 under the current demand signal path condition that processor 12 selects, carry out letter to the first signal to be demodulated and the second signal to be demodulated
Number debiasing and filtering processing after, carry out first time enhanced processing, when enhanced processing does not change signal phase.First time signal
After the completion of amplification, to guarantee signal waveform, it is filtered again by the filter circuit 1111 of the second level, wherein the second level
Filter circuit 1111 it is consistent with 1111 structure of filter circuit and parameter of the first order.After the completion of second is handled, for ensure by
Processing signal reaches larger amplitude angle value, need to carry out secondary amplification by the feeding amplifying circuit 1112 of the second level, enhanced processing does not change
Varying signal phase.After signal completes secondary amplification, the first processing signal and second processing signal of two opposite in phase are obtained, and
After two paths of signals feeding comparator 13 is compared, outgoing label return signal waveform is obtained, and guarantee that signal output amplitude is constant.
Treated that amplitude output signal is constant for comparator 13, and with reasons such as dynamic ranges larger change does not occur for signal waveform
Change, directly can handle I/O mouthfuls using control and be acquired processing.Wherein, processor 12 is preferably based on field-programmable gate array
(Field-Programmable Gate Array, FPGA) plate is arranged to realize.
Fig. 3 is the circuit diagram of Fig. 2, as shown in figure 3, every signal paths can be real using RC circuit in the present embodiment
It is existing.Wherein, the major influence factors of RC circuit are influence of the RC time constant to the response time and RC circuit to flowing through letter
Number the distortion factor influence: different reverse link rates, time code waiting time is different, and reverse link rate is bigger, the waiting time
It is shorter；Under same RC parameter, reverse link rate is smaller, and signal distortion is more serious；In this RC circuit, when to accelerate response
Between, it usually needs C value is smaller, but when the reduction of C value, low-frequency range waveform is easily distorted.
In circuit shown in Fig. 3, after comprehensively considering response time and distortion factor influence, when filter circuit 1111 is waited with returning code
Between (i.e. reverse rate size) be primary reference point, it is 4 grades that filter circuit 1111, which is divided, since circuit structure is consistent,
Each gear circuit configuration parameter is different.It is 1 grade that 4 gears, which are respectively as follows: 64K, returns code waiting time 15.625us；128K~
5.729~7.8125us of code waiting time is returned in 2 grades of the position 174.55K；274.29K~349.09K is three gears, returns the code waiting time
2.864~3.645us；Code waiting time 1.5625us is returned in 4 grades of the position 640K.The RC parameter configuration of each gear meets: full inspection wave
In dynamic range of signals, the signaling signal processing response time returns the code waiting time no more than the gear minimum；The gear all times
There is not serious distortion in the signal waveform of bit rate.
Two groups of signals to be demodulated that the processing of detection mechanism 10 obtains are initially entered RC circuit to carry out at debiasing and filtering
After reason, into the two-way operational amplification circuit 1112 in Fig. 3, processing is amplified to the amplitude of two groups of signals, completes the first order
Processing, later, into the RC circuit of the second level in Fig. 3, after being handled by RC circuit, enter back into check the mark amplifying circuit 1112 into
Row processing, enters back into comparator 13 and is handled, finally obtain the corresponding demodulated signal of current label return signal by processor
12 pairs of demodulated signals are acquired.
It should be noted that in practical applications, comparator 13 can be in order to further ensure exporting result stability
Two, after first comparator 13 obtains demodulated signal, second comparator 13 is inputted, by demodulated signal and a fixed thresholding
Information of voltage is compared, so that obtained demodulated signal is more stable.
Although above having made detailed description to the utility model with generality explanation and specific embodiment,
On the basis of the utility model, it can be made some modifications or improvements, this is apparent to those skilled in the art
's.Therefore, these modifications or improvements on the basis of without departing from the spirit of the present invention, belong to the utility model and want
Seek the range of protection.
Claims (10)
1. a kind of super high frequency radio frequency identification label signal demodulating equipment, which is characterized in that lead to including detection mechanism, with multi signal
Demodulating mechanism, comparator and the processor on road；
The detection mechanism, the demodulating mechanism, the comparator and the processor are sequentially connected；
The demodulating mechanism is also connected with the processor；
It is corresponding with the current state to control the demodulating mechanism gating according to the current state of read-write equipment for the processor
Current demand signal access；
Obtained according to label return signal first signal to be demodulated and the second signal to be demodulated are sent to by the detection mechanism
The demodulating mechanism；
The demodulating mechanism is used under the current demand signal access gating condition, is handled the described first signal to be demodulated
The the first processing signal obtained afterwards, and, the second processing signal obtained after handling the described second signal to be demodulated, and
The first processing signal and the second processing signal are sent to the comparator；
The comparator returns the obtained label after being compared to the first processing signal and second processing signal
A number corresponding demodulated signal of writing in reply is sent to the processor.
2. super high frequency radio frequency identification label signal demodulating equipment according to claim 1, which is characterized in that the demodulating machine
Structure is formed by the sub- regulating mechanism that multistage is sequentially connected；
Every grade of sub- regulating mechanism includes filter circuit and the amplifying circuit that is connected with the filter circuit；
Next stage amplifying circuit is also connected with upper level filter circuit；
Each filter circuit is connected with the processor；
Final stage amplifying circuit in final stage grade subsolution regulating mechanism is also connected with the comparator；
The filter circuit includes a plurality of signal path.
3. super high frequency radio frequency identification label signal demodulating equipment according to claim 2, which is characterized in that the amplification electricity
Road includes two-way operational amplification circuit or calculus of differences amplifying circuit.
4. super high frequency radio frequency identification label signal demodulating equipment according to claim 2, which is characterized in that every grade of son
Amplifying circuit in regulating mechanism is realized using identical tertiary circuit structure.
5. super high frequency radio frequency identification label signal demodulating equipment according to claim 4, which is characterized in that every grade of son
Amplifying circuit in regulating mechanism is realized using the 4th different circuit structures.
6. super high frequency radio frequency identification label signal demodulating equipment according to claim 1, which is characterized in that every bars is logical
It is realized using identical first circuit structure on road；
Each first circuit structure is corresponding with different circuit configuration parameters.
7. super high frequency radio frequency identification label signal demodulating equipment according to claim 6, which is characterized in that first electricity
Line structure is realized using RC circuit.
8. super high frequency radio frequency identification label signal demodulating equipment according to claim 1, which is characterized in that every bars is logical
It is realized using different second circuit structures on road.
9. -8 any super high frequency radio frequency identification label signal demodulating equipment according to claim 1, which is characterized in that described
Detection mechanism, from wavelength control is carried out, makes the described first letter to be demodulated by two geophone intervals to the label return signal
Number and the described second signal to be demodulated opposite in phase.
10. super high frequency radio frequency identification label signal demodulating equipment according to claim 9, which is characterized in that described first
The phase difference of the phase of signal to be demodulated and the second signal to be demodulated is 180 °.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN108595994A (en) * | 2018-04-25 | 2018-09-28 | 昆明联诚科技股份有限公司 | Super high frequency radio frequency identification label signal demodulating equipment |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN108595994A (en) * | 2018-04-25 | 2018-09-28 | 昆明联诚科技股份有限公司 | Super high frequency radio frequency identification label signal demodulating equipment |
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