CN202600754U - RFID (Radio Frequency Identification) tag with light-sensitive device and RFID system - Google Patents
RFID (Radio Frequency Identification) tag with light-sensitive device and RFID system Download PDFInfo
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- CN202600754U CN202600754U CN 201220257690 CN201220257690U CN202600754U CN 202600754 U CN202600754 U CN 202600754U CN 201220257690 CN201220257690 CN 201220257690 CN 201220257690 U CN201220257690 U CN 201220257690U CN 202600754 U CN202600754 U CN 202600754U
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Abstract
The utility model provides an RFID (Radio Frequency Identification) tag with a light-sensitive device and an RFID system. A parallel structure is formed by the light-sensitive device and an antenna of the RFID tag; an on-off control logic circuit is arranged on a connection line of the light-sensitive device and a chip of the RFID tag; the connection line and the on-off control logic circuit are a part of the chip; when the logic circuit is switched off, the light-sensitive device is not in parallel connection with the antenna, at the moment, the RFID tag is placed under certain light intensity, and the first resonant frequency and the signal intensity of the antenna remain unchanged when; when the logic circuit is switched on, the light-sensitive device is in parallel connection with the antenna, at the moment, the RFID tag is placed under certain light intensity, and the antenna works at second resonant frequency; and the RFID tag receives an instruction transmitted by an RFID reader so as to control the on/off of the logic circuit, and thus, the change of illumination can be detected through comparing the differences among intensities of signals from the antenna, with different frequencies. The RFID tag and the RFID system can detect illumination changes with lower cost.
Description
Technical field
The utility model relates to RFID (Radio Frequency Identification, RF identification) technical field, relates in particular to a kind of RFID label, rfid system with light-sensitive unit.
Background technology
In recent years, rfid system had become more prevalent.Rfid system is mainly used in the identification to people and thing.In general, this system comprises a RFID reader at least, and the radiofrequency signal from one or more RFID labels can launched and accept to this RFID reader in the scope of a setting.This RFID label generally encapsulates, and can be attached on the object, and it comprises the microchip that an ability and antenna carry out information interchange.This microchip is an integrated circuit in general, and it can be used for storing and process information, the modulation radiofrequency signal, and can move other specific function.The antenna of RFID label is to be used for receiving and sending radiofrequency signal, and is applicable to a kind of special frequency usually.
In some equipment, when the intensity of illumination that the rfid system that has light-sensitive unit has been used to monitor product environment of living in has surpassed the acceptable intensity of illumination.In general these equipment requirements induction installations will have a lasting energy source, are used for detecting the change of illumination, but this can increase the cost of equipment.In addition, some equipment requirements induction installations also will link to each other with a comparator circuit, thereby detect the degree size that departs from reference voltage, and this requirement has increased the cost of equipment greatly.In a word, improve rfid system and be necessary, its requires when not using lasting energy source or use a kind of adjunct circuit cheaply, can be used for detecting illumination variation.
The utility model content
The utility model embodiment provides a kind of RFID label, rfid system with light-sensitive unit, detects illumination variation at lower cost.
On the one hand, the utility model embodiment provides a kind of RFID label with light-sensitive unit, and two pins are arranged on the chip of said RFID label; Two pins of said light-sensitive unit and this link to each other; And form parallel-connection structure with the antenna of said RFID label; The variation of ambient light photograph can cause the changes in resistance of light-sensitive unit own, and the logical circuit of a control break-make is arranged on said light-sensitive unit and circuit that the chip of RFID label is connected, and the circuit of this connection is the part of chip with the logical circuit of control break-make; The break-make of logical circuit determined light-sensitive unit whether with the sky line parallel: when logical circuit breaks off; Light-sensitive unit not with the sky line parallel, this moment be placed under certain intensity of illumination, first resonant frequency and the signal intensity of antenna remain unchanged; When logical circuit was connected, light-sensitive unit was placed under certain intensity of illumination with a day line parallel, this moment, and the characteristic frequency of antenna and signal intensity have one at least and change, and this moment, antenna was operated under second resonant frequency; Said RFID label receives the break-make of the instruction of RFID reader transmission with control logic circuit, thereby realizes detecting from the difference between the signal intensity of the different frequency of antenna through comparison the change of illumination.
Optional, in the utility model one embodiment, the antenna of said RFID label is a monopole antenna.
Optional, in the utility model one embodiment, the antenna of said RFID label is a double-doublet antenna: said light-sensitive unit forms parallel-connection structure with antenna wherein; Perhaps said light-sensitive unit and two antennas form parallel-connection structure simultaneously.
Optional, in the utility model one embodiment, said light-sensitive unit is the resistor-type light-sensitive unit, said resistor-type light-sensitive unit comprises: cadmium sulphide photoconductive cell device, cadmium slenide photoconductive cell device and other types photoresistance device.
On the other hand, the utility model embodiment provides a kind of RFID label with light-sensitive unit, and a pin is arranged on the chip of said RFID label; One end of said light-sensitive unit links to each other with this pin; The other end is connected on the antenna of said RFID label, and forms parallel-connection structure with antenna, and the variation of ambient light photograph can cause the changes in resistance of light-sensitive unit own; The logical circuit that a control break-make is arranged on said light-sensitive unit and circuit that the chip of RFID label is connected; The circuit of this connection is the part of chip with the logical circuit of control break-make, the break-make of logical circuit determined light-sensitive unit whether with the sky line parallel: when logical circuit breaks off, light-sensitive unit not with the sky line parallel; Be placed under certain intensity of illumination this moment, and first resonant frequency and the signal intensity of antenna remain unchanged; When logical circuit was connected, light-sensitive unit was placed under certain intensity of illumination with a day line parallel, this moment, and the characteristic frequency of antenna and signal intensity have one at least and change, and this moment, antenna was operated under second resonant frequency; Said RFID label receives the break-make of the instruction of RFID reader transmission with control logic circuit, thereby realizes detecting from the difference between the signal intensity of the different frequency of antenna through comparison the change of illumination.
Optional, in the utility model one embodiment, the antenna of said RFID label is a monopole antenna.
Optional, in the utility model one embodiment, the antenna of said RFID label is a double-doublet antenna: said light-sensitive unit forms parallel-connection structure with antenna wherein; Perhaps said light-sensitive unit and two antennas form parallel-connection structure simultaneously.
Optional, in the utility model one embodiment, said light-sensitive unit is the resistor-type light-sensitive unit, said resistor-type light-sensitive unit comprises: cadmium sulphide photoconductive cell device, cadmium slenide photoconductive cell device and other types photoresistance device.
Another aspect; The utility model embodiment provides a kind of RFID label with light-sensitive unit; Said light-sensitive unit is connected on the antenna of said RFID label, and forms parallel-connection structure with antenna, and the variation of ambient light photograph can cause the changes in resistance of light-sensitive unit own; The logical circuit that a control break-make is arranged on said light-sensitive unit and circuit that antenna is connected; The circuit of this connection is the part of chip with the logical circuit of control break-make, the break-make of logical circuit determined light-sensitive unit whether with the sky line parallel: when logical circuit breaks off, light-sensitive unit not with the sky line parallel; Be placed under certain intensity of illumination this moment, and first resonant frequency and the signal intensity of antenna remain unchanged; When logical circuit was connected, light-sensitive unit was placed under certain intensity of illumination with a day line parallel, this moment, and the characteristic frequency of antenna and signal intensity have one at least and change, and this moment, antenna was operated under second resonant frequency; Said RFID label receives the break-make of the instruction of RFID reader transmission with control logic circuit, thereby realizes detecting from the difference between the signal intensity of the different frequency of antenna through comparison the change of illumination.
Optional, in the utility model one embodiment, the antenna of said RFID label is a monopole antenna.
Optional, in the utility model one embodiment, the antenna of said RFID label is a double-doublet antenna: said light-sensitive unit forms parallel-connection structure with antenna wherein; Perhaps said light-sensitive unit and two antennas form parallel-connection structure simultaneously.
Optional, in the utility model one embodiment, said light-sensitive unit is the resistor-type light-sensitive unit, said resistor-type light-sensitive unit comprises: cadmium sulphide photoconductive cell device, cadmium slenide photoconductive cell device and other types photoresistance device.
On the one hand, the utility model embodiment provides a kind of rfid system with light-sensitive unit again, and said rfid system comprises RFID label and RFID reader, and said RFID label comprises the RFID label of above-mentioned band light-sensitive unit; Said RFID reader sends the break-make of instruction with the logical circuit of control RFID label, thereby detects the change of illumination from the difference between the signal intensity of the different frequency of antenna through comparison.
Technique scheme has following beneficial effect: because adopt the antenna of said light-sensitive unit and said RFID label to form parallel-connection structure; The logical circuit that a control break-make is arranged on said light-sensitive unit and circuit that the chip of RFID label is connected; The circuit of this connection is the part of chip with the logical circuit of control break-make;: when logical circuit breaks off; Light-sensitive unit not with the sky line parallel, this moment be placed under certain intensity of illumination, first resonant frequency and the signal intensity of antenna remain unchanged; When logical circuit was connected, light-sensitive unit was placed under certain intensity of illumination with a day line parallel, this moment, and this moment, antenna was operated under second resonant frequency; Said RFID label receives the break-make of the instruction of RFID reader transmission with control logic circuit; Thereby realize detecting from the difference between the signal intensity of the different frequency of antenna the technological means of the change of illumination through comparison; So reached the technique effect that detects illumination variation at lower cost; And the energy that utilizes RFID to obtain, solved the powerup issue that illumination detects.
Description of drawings
In order to be illustrated more clearly in the utility model embodiment or technical scheme of the prior art; To do to introduce simply to the accompanying drawing of required use in embodiment or the description of the Prior Art below; Obviously, the accompanying drawing in describing below only is some embodiment of the utility model, for those of ordinary skills; Under the prerequisite of not paying creative work, can also obtain other accompanying drawing according to these accompanying drawings.
The synoptic diagram that Fig. 1 is connected with the RFID label chip for the utility model embodiment light-sensitive unit;
Fig. 2 is the equivalent circuit diagram of RFID label chip inside antenna;
Fig. 3 is the synoptic diagram that the utility model embodiment light-sensitive unit, logic switch are connected with RFID label chip inside antenna equivalent electrical circuit;
The synoptic diagram that Fig. 4 directly is connected for the utility model embodiment light-sensitive unit and RFID label antenna;
Fig. 5 .1-Fig. 5 .2 is the structure key diagram of the utility model embodiment light-sensitive unit;
Fig. 6 is the process flow diagram of the utility model embodiment based on the illumination level detection method of signal intensity.
Embodiment
To combine the accompanying drawing among the utility model embodiment below, the technical scheme among the utility model embodiment is carried out clear, intactly description, obviously, described embodiment only is the utility model part embodiment, rather than whole embodiment.Based on the embodiment in the utility model, those of ordinary skills are not making the every other embodiment that is obtained under the creative work prerequisite, all belong to the scope of the utility model protection.
The light-sensitive unit of the utility model embodiment links to each other with the chip of RFID label and has three kinds of situation at least:
The two pins structure:
The utility model embodiment is a kind of device, system and technology that is used for detecting illumination variation.This system has comprised a RFID label, and two pins are arranged on the chip of this RFID label.Two pins of light-sensitive unit and this link to each other, and form parallel-connection structure with antenna.The variation of ambient light photograph can cause the changes in resistance of light-sensitive unit own.The logical circuit of a control break-make is arranged on pin and circuit that chip is connected, and the circuit of this connection is the part of chip with the logical circuit of control break-make.The break-make of logical circuit determined light-sensitive unit whether with the sky line parallel.
When logical circuit breaks off, light-sensitive unit not with the sky line parallel, this moment be placed under certain intensity of illumination, first resonant frequency and the signal intensity of antenna remain unchanged.When logical circuit was connected, light-sensitive unit was placed under certain intensity of illumination with a day line parallel, this moment, and the characteristic frequency of antenna and signal intensity have one at least and change, and this moment, antenna was operated under second resonant frequency.The RFID reader can send the break-make of instruction control logical circuit to label, when logical circuit is connected, can detect the change of illumination through comparison from the difference between the signal intensity of the different frequency of antenna.
With regard to an instance, this system has comprised a RFID label, has only an antenna on this label.Two pins are arranged on the chip of this label.Two pins of light-sensitive unit and this link to each other, and form parallel-connection structure with this root antenna.The logical circuit of a control break-make is arranged on pin and circuit that chip is connected, and the logical circuit of the circuit of this connection and control break-make is the part of chip.The variation of ambient light photograph can cause the changes in resistance of light-sensitive unit own.
When logical circuit is connected, be placed under certain intensity of illumination, the characteristic frequency of antenna and signal intensity have one at least and change, and this moment, antenna was operated under second resonant frequency.The RFID reader can send instruction to label, and the difference between the signal intensity of the different frequency during through the comparison logic break-make can detect the change of illumination.Or rather, light-sensitive unit should have lower resistance, and its instantiation comprises: cadmium sulphide photoconductive cell device, cadmium slenide photoconductive cell device and other types photoresistance device etc.
With regard to another instance, this system has comprised a RFID label, and two antennas are arranged on this label.Two kinds of situation are arranged this moment.First kind of situation is that two pins of light-sensitive unit and this link to each other, and forms parallel-connection structure with first antenna.The logical circuit of a control break-make is arranged on pin and circuit that chip is connected, and the logical circuit of the circuit of this connection and control break-make is the part of chip.The variation of ambient light photograph can cause the changes in resistance of light-sensitive unit own.And second antenna is all the time with the first resonant frequency proper communication.
When logical circuit is connected, be placed under certain intensity of illumination, the characteristic frequency of first antenna and signal intensity have at least a meeting to change, and it is operated under second resonant frequency.The RFID reader can send instruction to label, and the difference between the signal intensity of the different frequency of first and second antennas can detect the change of illumination when connecting through comparison logic.Difference between the signal intensity of the different frequency during logical circuit break-make through second antenna self relatively also can detect the change of illumination.
Second kind of situation is that two pins of light-sensitive unit and this link to each other, and form parallel-connection structure simultaneously with two antennas.The logical circuit of a control break-make is arranged on pin and circuit that chip is connected, and the logical circuit of the circuit of this connection and control break-make is the part of chip.The variation of extraneous intensity of illumination can cause the changes in resistance of light-sensitive unit own.The situation that this and label only contain an antenna is similar.When logical circuit is connected, be placed under certain intensity of illumination, antenna features frequency and signal intensity have one at least and change, and it is operated under second resonant frequency.The RFID reader can send instruction to label, and the difference between the signal intensity of the different frequency during through the comparison logic break-make can detect the change of illumination.First kind of situation circuit connection is fairly simple, and the resonant frequency of two antennas maybe be different during work, can influence the precision of measurement.Second kind of situation circuit connects more complicated, but the resonant frequency of two antennas is consistent during work, and measuring accuracy is higher.Or rather, light-sensitive unit should have lower resistance, and its instantiation comprises: cadmium sulphide photoconductive cell device, cadmium slenide photoconductive cell device and other types photoresistance device etc.
One pin configuration:
The chip of this label can only have a pin, and this pin outwards links to each other with an end of light-sensitive unit, and the other end of light-sensitive unit is directly linked on the antenna.Pin is similar in the situation of the tie point of chip internal and two pins, finally remains the purpose that will reach with day line parallel.Simultaneously on pin and circuit that the chip internal circuit is connected, a logical circuit of controlling break-make is arranged.When logical circuit breaks off, light-sensitive unit not with the sky line parallel, this moment be placed under certain intensity of illumination, first resonant frequency and the signal intensity of antenna remain unchanged.
When logical circuit was connected, light-sensitive unit was placed under certain intensity of illumination with a day line parallel, this moment, and antenna features frequency and signal intensity have one at least and change, and it is operated under second resonant frequency.The RFID reader can send the break-make of instruction control logical circuit to label, when logical circuit is connected, can detect the change of illumination through comparison from the difference between the signal intensity of the different frequency of antenna.
With regard to an instance, this system has comprised a RFID label, has only an antenna on this label.A pin is arranged on the chip of this label.Light-sensitive unit links to each other with this pin, and the light-sensitive unit other end is directly linked on the antenna, forms parallel-connection structure with antenna.The logical circuit of a control break-make is arranged on pin and circuit that chip is connected, and the logical circuit of the circuit of this connection and control break-make is the part of chip.The variation of extraneous intensity of illumination can cause the changes in resistance of light-sensitive unit own.When logical circuit is connected, be placed under certain intensity of illumination, antenna is operated under second resonant frequency, and its characteristic frequency and signal intensity have one at least and change.The RFID reader can send instruction to label, and the difference between the signal intensity of the different frequency during through the comparison logic break-make can detect the change of intensity of illumination.Or rather, light-sensitive unit should have lower resistance, and its instantiation comprises: cadmium sulphide photoconductive cell device, cadmium slenide photoconductive cell device and other types photoresistance device etc.
With regard to another instance, this system has comprised a RFID label, and two antennas are arranged on this label.A pin is arranged on the chip of this label.Light-sensitive unit links to each other with this pin, and the light-sensitive unit other end is directly linked on the antenna, forms parallel-connection structure with first antenna.The logical circuit of a control break-make is arranged on pin and circuit that chip is connected, and the logical circuit of the circuit of this connection and control break-make is the part of chip.The variation of ambient light photograph can cause the changes in resistance of light-sensitive unit own.And second antenna is all the time with the first resonant frequency communication.
When logical circuit is connected, be placed under certain intensity of illumination, first antenna is operated under second resonant frequency, and its characteristic frequency and signal intensity have at least a meeting to change.The RFID reader can send instruction to label, and the difference between the signal intensity of the different frequency of first and second antennas can detect the change of illumination when connecting through comparison logic.Difference between the signal intensity of the different frequency during logical circuit break-make through first antenna self relatively also can detect the change of illumination.Or rather, light-sensitive unit should have lower resistance, and its instantiation comprises: cadmium sulphide photoconductive cell device, cadmium slenide photoconductive cell device and other types photoresistance device etc.
No pin configuration:
When not having pin on the chip of RFID label, light-sensitive unit can directly be linked on the antenna.In this case, the antenna that links to each other with light-sensitive unit can not break away from light-sensitive unit and with normal frequency for communication.When being placed under certain intensity of illumination, the characteristic frequency of antenna and signal intensity have one at least and change.The RFID reader can send instruction to label apparatus, detects the change of intensity of illumination from the difference between the signal intensity of the different frequency of antenna through comparison.
With regard to an instance, this system has comprised a RFID label, and two antennas are arranged on this label.Light-sensitive unit directly links to each other with first antenna, and second antenna do not link to each other with light-sensitive unit all the time with the first resonant frequency proper communication.When being placed under certain intensity of illumination, first antenna is operated under second resonant frequency, and its characteristic frequency and signal intensity have at least a meeting to change, and the characteristic frequency of second antenna and signal intensity are constant.The RFID reader can send instruction to label, and can detect the change of illumination through the difference between the signal intensity of the different frequency of first and second antennas relatively.Or rather, light-sensitive unit should have lower resistance, and its instantiation comprises: cadmium sulphide photoconductive cell device, cadmium slenide photoconductive cell device and other types photoresistance device etc.
In the same way, can be with on the chip of antenna also and can not be with pin, can be with one also can be with a plurality of pins.The radical of antenna can be one, two or even many.Also can connect one or more light-sensitive units accordingly, the model of light-sensitive unit can be the same or different simultaneously.With regard to a kind of instantiation of device, when being placed under certain intensity of illumination, the characteristic frequency of the antenna that links to each other with light-sensitive unit and signal intensity have at least a meeting to change.The RFID reader can send instruction to label apparatus, detects the change of illumination from the difference between the signal intensity of the different frequency of antenna through comparison.
With regard to a kind of instantiation of light-sensitive unit, the method for simultaneous comparison numerical value comprises that these are compared numerical value compares with most signal strength values.These signal strength values belong to different frequencies, and interrelate with the illumination value of majority, can detect the intensity of illumination simultaneously based on the above-mentioned comparison of mentioning.
Yet with regard to another aspect, a rfid system comprises a RFID label apparatus and a RFID reader device.This RFID label apparatus is used to send two kinds of signals, the signal when signal when promptly above-mentioned logical circuit breaks off and logical circuit are connected, and these two kinds of signals have at least a kind of meeting that the request that receives is responded.The RFID reader device is used for the RFID label apparatus is sent a request at least.Fiducial value between the signal strength values when reading device being installed being signal strength values and logical circuit in order accepting to connect and to break off from the logical circuit of label, and be converted into these fiducial values the varying level of illumination.
In an example, the antenna of RFID label links to each other with light-sensitive unit, and the logical circuit of a control break-make is arranged on this connection line.Under logical circuit break-make whether two kinds of situation, have two kinds of corresponding with it different frequencies with antenna.Connect and be positioned over this label apparatus under certain intensity of illumination when logical circuit,, will produce the intensity level of unlike signal owing to the variation of resonant frequency.
In an example, the RFID label apparatus comprises first, second two antennas.Better situation is, first antenna links to each other with light-sensitive unit, when this label apparatus is placed under certain intensity of illumination, owing to the variation of resonant frequency, will produce the difference of signal strength values under second resonant frequency.
On the one hand, the utility model embodiment provides a kind of rfid system with light-sensitive unit again, and said rfid system comprises RFID label and RFID reader, and said RFID label comprises the RFID label of above-mentioned band light-sensitive unit; Said RFID reader sends the break-make of instruction with the logical circuit of control RFID label, thereby detects the change of illumination from the difference between the signal intensity of the different frequency of antenna through comparison.
As shown in Figure 1, the synoptic diagram of the light sensitive tag 10 that is connected with the RFID label chip for the utility model embodiment light-sensitive unit.Among Fig. 1, label apparatus 10 comprises 13, two pins 16,17 of 15, one surface-mounted integrated circuits of a base and a double-doublet antenna 11,12.Two pins 16,17 are arranged on the surface-mounted integrated circuit 13, and these two pins outwards link to each other with light-sensitive unit 14, and these two pins are parallelly connected with the equivalent electrical circuit of antenna at chip internal, and the logical circuit of a control break-make is arranged on the circuit that connects.Whether photosensitive module can be controlled by in the access chip circuit through the break-make of logical circuit, thereby the frequency of the antenna that links to each other with radio-frequency module can be influenced.When logical circuit broke off, label antenna was with the first resonant frequency communication.When logical circuit is connected, be placed under certain intensity of illumination, antenna is operated under second resonant frequency, and its characteristic frequency and signal intensity have one at least and change.
In an example, transmitting terminal 11,12 is processed by one or more different low electrical resistant materials, and these materials have higher electric conductivity; Copper for example, silver, and aluminium; They link to each other with antenna 11,12 through two pins 16,17 with the above-mentioned light-sensitive unit of mentioning; When antenna 11,12 is placed under certain intensity of illumination, light-sensitive unit can cause the variation of one or more transmitting terminal generation resonant frequencies.The frequency of the frequency of this variation and reception and transmission is all different.For example, light-sensitive unit is positioned under certain intensity of illumination, will cause sending frequency and accept that at least one changes in the frequency.
In another example, the antenna frequencies value of setting at the beginning will be higher than the antenna frequencies under certain photoenvironment, and when reaching certain illumination, it will reduce then.In another example, the antenna frequencies of setting at the beginning is lower than the antenna frequencies under certain illumination level, and it will rise when reaching certain illumination level.The such light-sensitive unit that can be used for the utility model has: cadmium sulphide photoconductive cell device, cadmium slenide photoconductive cell device and other types photoresistance device etc.
Type based on light-sensitive unit is different, and the illumination level that causes changing possibly be that a specific illumination value also possibly be a scope of illumination value selectively.The length of time must cause the variation of antenna resonance frequency, and antenna quality also can cause different variations.The type of the light-sensitive unit that for example, has on the antenna can influence the length that changes the antenna resonance frequency required time.
As shown in Figure 2, be the equivalent circuit diagram of RFID label antenna.In the alternating magnetic field that tag coil antenna entering read write line produces, the interaction between label antenna and the reading and writing device antenna just is similar to transformer.Both coils are equivalent to the primary coil and the secondary coil of transformer.Resonant tank by label antenna forms is as shown in Figure 2, comprises coil inductance (L), the stray capacitance (C of label antenna
p) and shunt capacitance (C
2), its resonance frequency does
C is C in the formula
pAnd C
2Parallelly connected equivalent capacity, R
1, R
2Equivalent resistance for circuit internal inductance coil and other devices.The carrier frequency that label and read write line two-way communication are used is exactly f.The tag antenna coil profile is very little when requiring; Be that area is little; And need certain operating distance, the aerial coil mutual induction amount that RFID label and read write line are asked just obviously can not practical requirement, can have the Ferrite Material of high permeability in the inner insertion of tag antenna coil; With the increase mutual induction amount, thus the little problem of compensating coil xsect.
As shown in Figure 3, be the synoptic diagram that is connected with RFID label antenna equivalent electrical circuit of logical circuit of the utility model embodiment light-sensitive unit, control break-make.Resonant tank by label antenna forms is as shown in the figure, comprises coil inductance (L), the stray capacitance (C of label antenna
p) and shunt capacitance (C
2), its resonance frequency does
Formula C is C
pAnd C
2Parallelly connected equivalent capacity, R
1, R
2Equivalent resistance for circuit internal inductance coil and other devices.M is the variable resistor of representative light-sensitive unit, and S is the logical circuit of control break-make.When logical circuit breaks off, light-sensitive unit not with the sky line parallel, this moment be placed under certain intensity of illumination, first resonant frequency and the signal intensity of antenna remain unchanged.When logical circuit was connected, light-sensitive unit was placed under certain intensity of illumination with a day line parallel, this moment, and antenna is operated under second resonant frequency, and its characteristic frequency and signal intensity have one at least and change.
As shown in Figure 4, can detect the sketch of the passive RFID tags device 40 of illumination variation for the utility model embodiment.As shown in Figure 4, label apparatus 40 comprises 45, one integrated circuit 43 of a base and a double-doublet antenna 41,42.The light-sensitive unit 44 that links to each other with antenna 42 will influence the resistance of antenna 42.The material that light-sensitive unit 44 is suitable for can be controlled the frequency that any one had both been fixed a point according to any one current voltage in the antenna 41,42.With regard to an instance, fixing up an aerial wire 41,42 can make it produce resonance in identical frequency.With regard to another instance, fixing up an aerial wire 41,42 can make it produce resonance in different frequency.
In an example, transmitting terminal double- doublet antenna 41,42 is processed by one or more different low electrical resistant materials; These materials have higher electric conductivity, copper for example, silver; And aluminium, they link to each other with the above-mentioned light-sensitive unit of mentioning, when antenna 41; 42 are placed under certain intensity of illumination, and light-sensitive unit can cause the variation of one or more transmitting terminal generation resonant frequencies, thereby cause a different frequency.The frequency of the variation of this frequency and reception and transmission is all different.For example, light-sensitive unit is positioned under certain intensity of illumination, will cause sending frequency and accept that at least one changes in the frequency.
In another example, the antenna frequencies value of setting at the beginning will be higher than the antenna frequencies under certain photoenvironment, and when reaching certain illumination, it will reduce then.In another example, the antenna frequencies of setting at the beginning is lower than the antenna frequencies under certain illumination level, and it will rise when reaching certain illumination level.The such light-sensitive unit that can be used for this utility model has: cadmium sulphide photoconductive cell device, cadmium slenide photoconductive cell device and other types photoresistance device etc.
Type based on light-sensitive unit is different, and the illumination level that causes changing possibly be that a specific illumination value also possibly be a scope of illumination value selectively.The length of time must cause the variation of antenna resonance frequency, and antenna quality also can cause different variations.The type of the light-sensitive unit that for example, has on the antenna can influence the length that changes the antenna resonance frequency required time.
Shown in Fig. 5 .1; This device comprises that two electrodes are respectively 511; The action principle of 512 and photosensitive semiconductor thin layer 513. photoresistance is based on photoconductive effect, it have highly sensitive, volume is little, quality is little, spectral response range is wide, shock-resistant, characteristics such as dissipated power is big, the life-span is long.Because photoconductive effect is only limited to the skin layer of illumination, so all does straticulation the optoelectronic semiconductor 513 (like cadmium sulfide).In order to obtain high sensitivity, the electrode of photoresistance generally adopts pectination, like figure.The principle of work of photoresistance: when unglazed the photograph, the resistance of photoresistance is very high.When receiving illumination; Because some photon has the energy greater than the material energy gap; Then the bombardment of photon makes after the Electron absorption photon energy in the valence band and transits to conduction band, thereby inspires the electron-hole pair that can conduct electricity, and has improved the electric conductivity of material.The electronics of the stronger then participation of light bombardment is many more, and the electron-hole pair that inspires is many more, and electric conductivity improves more, and resistance is also just low more.After illumination stopped, free electron-sky was compound to the cave, and electric conductivity descends, and resistance value is replied initial value.
Shown in Fig. 5 .2, photoresistance is the particular resistor of processing with semiconductor material 522 material such as cadmium sulfide or cadmium selenides, and the surface scribbles Moisture barrier resins, has photoconductive effect.Photoresistance is very responsive to light, and it is when unglazed the photograph, and resistance value (dark resistance) is very big, and electric current in the circuit (dark current) is very little.When resistance received the illumination of certain wavelength coverage, its resistance (light resistance) sharply reduced, and electric current increases rapidly in the circuit.Hope that generally dark resistance is the bigger the better, light resistance is more little good more, and the sensitivity of photoresistance this moment is high more.The dark resistance value of photoresistance is generally in mega-ohms, and light resistance is below several kilo-ohms.Figure is the principle mechanism figure of photoresistance.It is the thin layer semiconductor substance 522 that is applied on the glass plate 523, and there is metal electrode 521 at the two ends of semiconductor 522, metal electrode 521 with draw line end and be connected, photoresistance is just gone into circuit through the extension line termination.In order to prevent the influence of surrounding medium, on the photosensitive layer 522 of semiconductor, covered one deck paint film, the composition of paint film should make it maximum in photosensitive wavelength coverage internal transmission factor.
As shown in Figure 6, detect a kind of method flow diagram of lighting change through the label apparatus that uses many antennas for the utility model embodiment.What need consider is, the above-mentioned device of mentioning uses a label integrated circuit to carry out and the exchanging of a plurality of antennas.
As shown in Figure 6,50, the RFID reader sends energy and instruction to label apparatus.52, logical circuit is in the state of disconnection at initial time, and label apparatus is with the antenna received energy and the instruction that do not link to each other with light-sensitive unit.54, the electromagnetic wave that label apparatus will carry energy is converted into a DC (direct current) voltage, thereby just can make label carry out the requirement of indication.And this conversion need be used a charge pump, and a rectification circuit perhaps interconnects it, perhaps will use other energy conversion device.56, label apparatus sends signal through the sky alignment reader that does not link to each other with light-sensitive unit.58, the energy intensity of receiving signal is measured and write down to reader.60, reader sends the instruction of connecting logical circuit to label apparatus.62, label apparatus is used the antenna transmission data that link to each other with light-sensitive unit.64, the energy intensity of signal is received in the reader measurement.66, reader calculated goes out the fiducial value of a reaction signal intensity.68, reader changes into the different illumination value with fiducial value.With regard to an instance, reader can be set the signal that a time period is used for receiving label, if do not receive signal, reader will be recorded as 0 with signal intensity.
In this system, reader will compare its signal strength values with the label antenna that links to each other with light-sensitive unit from the signal strength values of the antenna that does not link to each other with light-sensitive unit as a reference value.Through receive from the signal that links to each other with light-sensitive unit with the transmitting terminal that does not link to each other with light-sensitive unit, reader can be collected the fiducial value of representing unlike signal intensity.Then, the RFID reader can be converted into the residing illumination level of label to such fiducial value.With regard to a concrete instance, disposing this RFID reader is to be converted into illumination value for the difference from the RF signal intensity that connects the antenna that does not perhaps connect light-sensitive unit that will receive through the reference data of using storage.
Best situation is, with the antenna that does not connect light-sensitive unit as a reference, can be with owing to the variation that coupling caused between label and the reader filters out.In addition, as before mention, light-sensitive unit is applied to the time length that variation and the label of the resistance value that can make it in the design be placed under the particular light and forms relation one to one.For example, light-sensitive unit is only positioned on an antenna, can allow like this to change within the specific limits as a kind of function from the signal of RFID label apparatus, and this function just antenna be placed on the function that just has after the time under certain illumination.The same, through using the utility model, under the passive condition of RFID label, the RFID reader can detect label apparatus whether be placed under certain illumination and this illumination whether within the acceptable range.
Do not use the various RFID labels of two antennas also can perceive the variation of illumination with light-sensitive unit, the variation that the variation of perceived light photograph is based on resonant frequency on the antenna also can recognize the variation that antenna receives signal.
For example pass through design to the antenna that links to each other with light-sensitive unit; The frequency that can make antenna is at ISM (Industrial Scientific Medical; Industry, science, medical science) the interior variation of frequency range, can connect this antenna that links to each other with light-sensitive unit and logical circuit on the label of standard.
For example label antenna can so be set in a concrete instance; Before in being exposed to certain photoenvironment; The resonant frequency of antenna is 902-928MHZ, but in a single day label is exposed in certain photoenvironment, because the influence of illumination; The resonant frequency of antenna is just reduced to 899.5-927.5MHZ; Frequency frequency range (902-928MHZ) at U.S. RFID is split into 52 channels, and reader can be skipped the channel that can not receive at random in these 52 channels, and the benefit of this jump of reader is exactly to prevent effectively that a plurality of readers from attempting the conflict of using same frequency to cause in same physical space.
For example in an example, RFID frequency range (902-928MHZ) is not to be divided into 52 channels but the antenna settings that on average has been divided into n channel tag is carried out work under this frequency range (902-928MHZ).Because label antenna links to each other with light-sensitive unit, so as long as illumination has surpassed the scope of predefined value, the frequency of operation of antenna tag antenna just drops among (899.5-927.5MHZ) this frequency range.Therefore compare just channel n to be got rid of from band limits with original frequency range and go, the frequency range (899.5-927.5MHZ) after therefore changing is carried out exchanging of information with regard to no longer allowing label with channel n.
In concrete instance; If the environment at label place has surpassed the illumination range of expection; Reader can only send instruction to label through channel 1 to n-1; Label also can be made a response because the antenna in the label just can only work in this frequency range, when reader with the frequency of n channel when label sends instruction; So no longer reach the 928MHZ label and just no longer make a response because the variation of label illumination has caused the resonant frequency of label antenna to drop to 899.5-927.5MHZ, pass information back reader.
Favourable aspect is just to be reflected by the disappearance of this information interchange owing to variation that illumination has exceeded the operating frequency of antenna that predefined value causes.
In model; Reader can send an instruction between channel n-1 and channel n to label and further check that drift has taken place the operating frequency range of label antenna; Because label can receive the instruction that sends through channel n-1; And can be to the reader feedback information through channel n-1; Because label can not receive the instruction that sends through channel n, and can not can so just confirm that drift has taken place the operating frequency range of label antenna to the reader feedback information through channel n.
The variation of illumination causes the frequency of operation of label antenna to take place upwards to be not limited in downward drift and present utility model frequency range on average is divided into n channel.
The utility model embodiment can detect illumination variation at lower cost, and the energy that utilizes RFID to obtain, and has solved the powerup issue that illumination detects.
The enforcement of each characteristics of this system may relate to software; The combination that hardware also possibly relate to software and hardware just can reach, and for example the enforcement of many advantages of system is to realize with the mutual mode that exchanges of computer and other equipment machines with object oriented programming languages with a kind of high-caliber processing through programming.Each such function program for example possibly be stored in the storage intermediary in the ROM (read-only memory) to be read by a computer and processor and realize above-mentioned function.
Those skilled in the art can also recognize the various illustrative components, blocks (illustrative logical block) that the utility model embodiment lists, and unit and step can be passed through electronic hardware, computer software, or both combinations realize.Be the clear replaceability (interchangeability) of showing hardware and software, above-mentioned various illustrative components (illustrative components), unit and step have been described their function generally.Such function is to realize depending on the designing requirement of certain applications and total system through hardware or software.Those skilled in the art can be for every kind of certain applications, and can make ins all sorts of ways realizes described function, but this realization should not be understood that to exceed the scope of the utility model embodiment protection.
Various illustrative logical block described in the utility model embodiment; Or the unit can pass through general processor, digital signal processor, special IC (ASIC); Field programmable gate array (FPGA) or other programmable logic device; Discrete gate or transistor logic, discrete hardware components, or the design of above-mentioned any combination realizes or operates described function.General processor can be microprocessor, and alternatively, this general processor also can be any traditional processor, controller, microcontroller or state machine.Processor also can realize through the combination of calculation element, for example digital signal processor and microprocessor, a plurality of microprocessors, Digital Signal Processor Core of one or more microprocessors associatings, or any other similarly configuration realize.
The method described in the utility model embodiment or the step of algorithm can directly embed hardware, the software module of processor execution or the two combination.Software module can be stored in the storage medium of other arbitrary form in RAM storer, flash memory, ROM storer, eprom memory, eeprom memory, register, hard disk, moveable magnetic disc, CD-ROM or this area.Exemplarily, storage medium can be connected with processor, so that processor can read information from storage medium, and can deposit write information to storage medium.Alternatively, storage medium can also be integrated in the processor.Processor and storage medium can be arranged among the ASIC, and ASIC can be arranged in the user terminal.Alternatively, processor and storage medium also can be arranged in the various parts in the user terminal.
In one or more exemplary designs, the described above-mentioned functions of the utility model embodiment can realize in hardware, software, firmware or this three's combination in any.If in software, realize, these functions can be stored on the media with computer-readable, or are transmitted on the media of computer-readable with one or more instructions or code form.The computer-readable media comprises that the computer storage medium lets computer program transfer to other local telecommunication media from a place with being convenient to make.Storage medium can be the useable medium that any general or special computer can access.For example; Such computer readable media can include but not limited to RAM, ROM, EEPROM, CD-ROM or other optical disc storage, disk storage or other magnetic storage device, or other any can be used to carry or store with instruction or data structure and other can be read the media of the program code of form by general or special computer or general or special processor.In addition; Any connection can suitably be defined as the computer-readable media; For example, if software is through a concentric cable, optical fiber computer, twisted-pair feeder, Digital Subscriber Line (DSL) or also being comprised in the defined computer-readable media with wireless mode transmission such as for example infrared, wireless and microwaves from a web-site, server or other remote resource.Described video disc (disk) and disk (disc) comprise Zip disk, radium-shine dish, CD, DVD, floppy disk and Blu-ray Disc, and disk is usually with the magnetic duplication data, and video disc carries out the optical reproduction data with laser usually.Above-mentioned combination also can be included in the computer-readable media.
Above-described embodiment; Purpose, technical scheme and beneficial effect to the utility model have carried out further explain, it should be understood that the above is merely the embodiment of the utility model; And be not used in the protection domain that limits the utility model; All within the spirit and principle of the utility model, any modification of being made, be equal to replacement, improvement etc., all should be included within the protection domain of the utility model.
Claims (10)
1. the RFID label with light-sensitive unit is characterized in that, two pins are arranged on the chip of said RFID label; Two pins of said light-sensitive unit and this link to each other; And form parallel-connection structure with the antenna of said RFID label; The variation of ambient light photograph can cause the changes in resistance of light-sensitive unit own, and the logical circuit of a control break-make is arranged on said light-sensitive unit and circuit that the chip of RFID label is connected, and the circuit of this connection is the part of chip with the logical circuit of control break-make; The break-make of logical circuit determined light-sensitive unit whether with the sky line parallel: when logical circuit breaks off; Light-sensitive unit not with the sky line parallel, this moment be placed under certain intensity of illumination, first resonant frequency and the signal intensity of antenna remain unchanged; When logical circuit was connected, light-sensitive unit was placed under certain intensity of illumination with a day line parallel, this moment, and the characteristic frequency of antenna and signal intensity have one at least and change, and this moment, antenna was operated under second resonant frequency; Said RFID label receives the break-make of the instruction of RFID reader transmission with control logic circuit, thereby realizes detecting from the difference between the signal intensity of the different frequency of antenna through comparison the change of illumination.
2. according to claim 1 with the RFID label of light-sensitive unit, it is characterized in that the antenna of said RFID label is a monopole antenna.
3. according to claim 1 with the RFID label of light-sensitive unit, it is characterized in that the antenna of said RFID label is a double-doublet antenna: said light-sensitive unit forms parallel-connection structure with antenna wherein; Perhaps said light-sensitive unit and two antennas form parallel-connection structure simultaneously.
4. the RFID label with light-sensitive unit is characterized in that, a pin is arranged on the chip of said RFID label; One end of said light-sensitive unit links to each other with this pin; The other end is connected on the antenna of said RFID label, and forms parallel-connection structure with antenna, and the variation of ambient light photograph can cause the changes in resistance of light-sensitive unit own; The logical circuit that a control break-make is arranged on said light-sensitive unit and circuit that the chip of RFID label is connected; The circuit of this connection is the part of chip with the logical circuit of control break-make, the break-make of logical circuit determined light-sensitive unit whether with the sky line parallel: when logical circuit breaks off, light-sensitive unit not with the sky line parallel; Be placed under certain intensity of illumination this moment, and first resonant frequency and the signal intensity of antenna remain unchanged; When logical circuit was connected, light-sensitive unit was placed under certain intensity of illumination with a day line parallel, this moment, and the characteristic frequency of antenna and signal intensity have one at least and change, and this moment, antenna was operated under second resonant frequency; Said RFID label receives the break-make of the instruction of RFID reader transmission with control logic circuit, thereby realizes detecting from the difference between the signal intensity of the different frequency of antenna through comparison the change of illumination.
5. like the RFID label of the said band light-sensitive unit of claim 4, it is characterized in that the antenna of said RFID label is a monopole antenna.
6. like the RFID label of the said band light-sensitive unit of claim 4, it is characterized in that the antenna of said RFID label is a double-doublet antenna: said light-sensitive unit forms parallel-connection structure with antenna wherein; Perhaps said light-sensitive unit and two antennas form parallel-connection structure simultaneously.
7. the RFID label with light-sensitive unit is characterized in that, said light-sensitive unit is connected on the antenna of said RFID label; And form parallel-connection structure with antenna; The variation of ambient light photograph can cause the changes in resistance of light-sensitive unit own, and the logical circuit of a control break-make is arranged on said light-sensitive unit and circuit that antenna is connected, and the circuit of this connection is the part of chip with the logical circuit of control break-make; The break-make of logical circuit determined light-sensitive unit whether with the sky line parallel: when logical circuit breaks off; Light-sensitive unit not with the sky line parallel, this moment be placed under certain intensity of illumination, first resonant frequency and the signal intensity of antenna remain unchanged; When logical circuit was connected, light-sensitive unit was placed under certain intensity of illumination with a day line parallel, this moment, and the characteristic frequency of antenna and signal intensity have one at least and change, and this moment, antenna was operated under second resonant frequency; Said RFID label receives the break-make of the instruction of RFID reader transmission with control logic circuit, thereby realizes detecting from the difference between the signal intensity of the different frequency of antenna through comparison the change of illumination.
8. like the RFID label of the said band light-sensitive unit of claim 7, it is characterized in that the antenna of said RFID label is a monopole antenna.
9. like the RFID label of the said band light-sensitive unit of claim 7, it is characterized in that the antenna of said RFID label is a double-doublet antenna: said light-sensitive unit forms parallel-connection structure with antenna wherein; Perhaps said light-sensitive unit and two antennas form parallel-connection structure simultaneously.
10. rfid system with light-sensitive unit, said rfid system comprises RFID label and RFID reader, it is characterized in that,
Said RFID label comprises the RFID label of each said band light-sensitive unit among the claim 1-3, or the RFID label of each said band light-sensitive unit among the claim 4-6, or the RFID label of each said band light-sensitive unit among the claim 7-9;
Said RFID reader sends the break-make of instruction with the logical circuit of control RFID label, thereby detects the change of illumination from the difference between the signal intensity of the different frequency of antenna through comparison.
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| CN 201220257690 CN202600754U (en) | 2012-06-01 | 2012-06-01 | RFID (Radio Frequency Identification) tag with light-sensitive device and RFID system |
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| Application Number | Priority Date | Filing Date | Title |
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| CN 201220257690 CN202600754U (en) | 2012-06-01 | 2012-06-01 | RFID (Radio Frequency Identification) tag with light-sensitive device and RFID system |
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| CN202600754U true CN202600754U (en) | 2012-12-12 |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103914726A (en) * | 2012-12-30 | 2014-07-09 | 章玺 | RFID (radio frequency identification) tag with light sensation module and anti-disassembly RFID tag |
| WO2017004891A1 (en) * | 2015-07-08 | 2017-01-12 | 中兴通讯股份有限公司 | Terminal having optically reconfigurable antenna |
| CN107346442A (en) * | 2017-06-30 | 2017-11-14 | 青岛海大新星计算机工程中心 | A kind of RFID of orientable identification |
| CN108351981A (en) * | 2015-11-03 | 2018-07-31 | 微软技术许可有限责任公司 | Non-rotationally-symmetric short-distance radio label |
| US10955977B2 (en) | 2015-11-03 | 2021-03-23 | Microsoft Technology Licensing, Llc | Extender object for multi-modal sensing |
| US11275910B2 (en) * | 2012-01-20 | 2022-03-15 | To Chin | Object identification system and method |
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2012
- 2012-06-01 CN CN 201220257690 patent/CN202600754U/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11275910B2 (en) * | 2012-01-20 | 2022-03-15 | To Chin | Object identification system and method |
| CN103914726A (en) * | 2012-12-30 | 2014-07-09 | 章玺 | RFID (radio frequency identification) tag with light sensation module and anti-disassembly RFID tag |
| WO2017004891A1 (en) * | 2015-07-08 | 2017-01-12 | 中兴通讯股份有限公司 | Terminal having optically reconfigurable antenna |
| CN108351981A (en) * | 2015-11-03 | 2018-07-31 | 微软技术许可有限责任公司 | Non-rotationally-symmetric short-distance radio label |
| CN108351981B (en) * | 2015-11-03 | 2021-01-15 | 微软技术许可有限责任公司 | Non-rotationally symmetric short-range wireless tag |
| US10955977B2 (en) | 2015-11-03 | 2021-03-23 | Microsoft Technology Licensing, Llc | Extender object for multi-modal sensing |
| CN107346442A (en) * | 2017-06-30 | 2017-11-14 | 青岛海大新星计算机工程中心 | A kind of RFID of orientable identification |
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| C14 | Grant of patent or utility model | ||
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| CF01 | Termination of patent right due to non-payment of annual fee | ||
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Granted publication date: 20121212 Termination date: 20170601 |