CN202694360U

CN202694360U - Radio frequency identification device (RFID) system capable of measuring flow and flow rate

Info

Publication number: CN202694360U
Application number: CN 201220259498
Authority: CN
Inventors: 刘丙午; 霍灵瑜; 王玉泉
Original assignee: Beijing Wuzi University
Current assignee: Beijing Wuzi University
Priority date: 2012-06-01
Filing date: 2012-06-01
Publication date: 2013-01-23
Anticipated expiration: 2022-06-01

Abstract

The utility model provides a radio frequency identification device (RFID) system capable of measuring flow and flow rate. The system comprises an RFID reader, a first RFID label and a second RFID label. The labels have the same chips and antennas. The first RFID label is placed under certain flow and flow rate level and works under first resonance frequency. The second RFID label is an RFID label with a flow and flow rate sensitive device, the flow and flow rate sensitive device and the antenna of the second RFID label form a parallel connection structure, a voltage-resistance conversion device is arranged on a circuit connecting the flow and flow rate sensitive device and the chip of the second RFID label, the connecting circuit and the voltage-resistance conversion device are a part of the chip, and the second RFID label is placed under certain flow and flow rate level and works under second resonance frequency. The first RFID label and the second RFID label receive commands sent by the RFID reader respectively and feed back signals, and the RFID reader detects changes of the flow and the flow rate by comparing difference of intensity of signals with different frequencies from the first RFID label and the second RFID label. The RFID system can detect changes of the flow and the flow rate with low cost.

Description

A kind of rfid system of measurement of discharge flow velocity

Technical field

The utility model relates to RFID (Radio Frequency Identification, radio-frequency (RF) identification) technical field, relates in particular to a kind of rfid system of measurement of discharge flow velocity.

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 be launched and accept to this RFID reader in the scope of a setting.This RFID label generally is encapsulated, can be attached on the object, it comprises the chip that an energy and antenna carry out information interchange, this chip is microchip, it is an integrated circuit in general, it can be used for storing and process information, the modulation /demodulation radiofrequency signal, and can move other specific function.The antenna of RFID label is to receive and the transmission radiofrequency signal, and usually is applicable to a kind of special frequency.

In some equipment, when the flow velocity that a kind of rfid system of measurement of discharge flow velocity has been used to monitor product environment of living in has surpassed the acceptable flow velocity.In general these equipment requirement induction installations will have a lasting energy source, are used for detecting the change of flow velocity, but this can increase the cost of equipment.In addition, some equipment requirement 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, it requires to be used for detecting flow velocity when not using lasting energy source or using a kind of cheaply adjunct circuit and changes.

The utility model content

The utility model embodiment provides a kind of rfid system of measurement of discharge flow velocity, detects at lower cost flow velocity and changes.

On the one hand, the utility model embodiment provides a kind of rfid system of measurement of discharge flow velocity, the rfid system of described measurement of discharge flow velocity comprises: RFID reader, a RFID label and the 2nd RFID label, and a described RFID label has identical chip and antenna with described the 2nd RFID label; A described RFID label is placed under certain flow velocity level, and the first resonant frequency and the signal intensity of the antenna of a described RFID label remain unchanged, and this moment, a described RFID label was operated under the first resonant frequency; Described the 2nd RFID label is the RFID label with the flow velocity sensor, and two pins are arranged on the chip of described the 2nd RFID label; Two pins of described flow velocity sensor and this link to each other, and form parallel-connection structure with the antenna of described the 2nd RFID label, the circuit that is connected with the chip of the 2nd RFID label at the flow velocity sensor has one voltage-resistance conversion equipment, the circuit of this connection and this voltage-resistance conversion equipment are the parts of chip, the variation of extraneous flow velocity can cause the variation of flow velocity sensor both end voltage or electric current, this moment, described the 2nd RFID label was placed under certain flow velocity level, the characteristic frequency of the antenna of described the 2nd RFID label and signal intensity have at least one and change, and this moment, described the 2nd RFID label was operated under the second resonant frequency; A described RFID label and described the 2nd RFID label receive respectively instruction and the feedback signal that described RFID reader sends, and described RFID reader is by relatively detecting the change of flow velocity from the difference between the signal intensity of a described RFID label and described the 2nd RFID label different frequency.

Optionally, in the utility model one embodiment, the antenna of a described RFID label and described the 2nd RFID label is monopole antenna: the antenna of described flow velocity sensor and described the 2nd RFID label forms parallel-connection structure.

Optionally, in the utility model one embodiment, the antenna of a described RFID label and described the 2nd RFID label is double-doublet antenna: an antenna of described flow velocity sensor and described the 2nd RFID label forms parallel-connection structure, perhaps forms simultaneously parallel-connection structure with two antennas.

Optionally, in the utility model one embodiment, described voltage-resistance conversion equipment comprises: a variable voltage converts the equivalent electrical circuit of variable-resistance device or a ditch type field effect transistor or field effect transistor to, and described flow velocity sensor comprises: vortex flow pick-up unit, turbine flow pick-up unit, electromagnetic flow pick-up unit, electromagnetic type flow monitor.

On the other hand, the utility model embodiment provides a kind of rfid system of measurement of discharge flow velocity, the rfid system of described measurement of discharge flow velocity comprises: RFID reader, a RFID label and the 2nd RFID label, and a described RFID label has identical chip and antenna with described the 2nd RFID label; A described RFID label is placed under certain flow velocity level, and the first resonant frequency and the signal intensity of the antenna of a described RFID label remain unchanged, and this moment, a described RFID label was operated under the first resonant frequency; Described the 2nd RFID label is the RFID label with the flow velocity sensor, and a pin is arranged on the chip of described the 2nd RFID label; One end of described flow velocity sensor links to each other with this pin, the other end is connected on the antenna of described RFID label, and form parallel-connection structure with antenna, the circuit that is connected with the chip of the 2nd RFID label at the flow velocity sensor has one voltage-resistance conversion equipment, the circuit of this connection and this voltage-resistance conversion equipment are the parts of chip, the variation of extraneous flow velocity can cause the variation of flow velocity sensor both end voltage or electric current, this moment, described the 2nd RFID label was placed under certain flow velocity level, the characteristic frequency of the antenna of described the 2nd RFID label and signal intensity have at least one and change, and this moment, described the 2nd RFID label was operated under the second resonant frequency; A described RFID label and described the 2nd RFID label receive respectively instruction and the feedback signal that described RFID reader sends, and described RFID reader is by relatively detecting the change of flow velocity from the difference between the signal intensity of a described RFID label and described the 2nd RFID label different frequency.

Another aspect, the utility model embodiment provides a kind of rfid system of measurement of discharge flow velocity, the rfid system of described measurement of discharge flow velocity comprises: RFID reader, a RFID label and the 2nd RFID label, and a described RFID label has identical chip and antenna with described the 2nd RFID label; A described RFID label is placed under certain flow velocity level, and the first resonant frequency and the signal intensity of the antenna of a described RFID label remain unchanged, and this moment, a described RFID label was operated under the first resonant frequency; Described the 2nd RFID label is the RFID label with the flow velocity sensor, described flow velocity sensor is connected on the antenna of described RFID label, and form parallel-connection structure with antenna, the circuit that is connected with the chip of the 2nd RFID label at the flow velocity sensor has one voltage-resistance conversion equipment, the circuit of this connection and this voltage-resistance conversion equipment are the parts of chip, the variation of extraneous flow velocity can cause the variation of flow velocity sensor both end voltage or electric current, this moment, described the 2nd RFID label was placed under certain flow velocity level, the characteristic frequency of the antenna of described the 2nd RFID label and signal intensity have at least one and change, and this moment, described the 2nd RFID label was operated under the second resonant frequency; A described RFID label and described the 2nd RFID label receive respectively instruction and the feedback signal that described RFID reader sends, and described RFID reader is by relatively detecting the change of flow velocity from the difference between the signal intensity of a described RFID label and described the 2nd RFID label different frequency.

Technique scheme has following beneficial effect: because adopt the rfid system of described measurement of discharge flow velocity to comprise: RFID reader, a RFID label and the 2nd RFID label, and a described RFID label has identical chip and antenna with described the 2nd RFID label; A described RFID label is placed under certain flow velocity level, and a described RFID label is operated under the first resonant frequency; Described the 2nd RFID label is the RFID label with the flow velocity sensor, the antenna of described flow velocity sensor and described the 2nd RFID label forms parallel-connection structure, the circuit that is connected with the chip of the 2nd RFID label at the flow velocity sensor has one voltage-resistance conversion equipment, the circuit of this connection and this voltage-resistance conversion equipment are the parts of chip, this moment, described the 2nd RFID label was placed under certain flow velocity level, and described the 2nd RFID label is operated under the second resonant frequency; A described RFID label and described the 2nd RFID label receive respectively instruction and the feedback signal that described RFID reader sends, described RFID reader is by relatively detecting the technological means of the change of flow velocity from the difference between the signal intensity of a described RFID label and described the 2nd RFID label different frequency, so reached and detected at lower cost the technique effect that flow velocity changes, and the energy that utilizes RFID to obtain, solved the powerup issue that flow velocity detects.

Description of drawings

In order to be illustrated more clearly in the utility model embodiment or technical scheme of the prior art, the below will do to introduce simply to the accompanying drawing of required use in embodiment or the description of the Prior Art, apparently, accompanying drawing in the following describes only is embodiment more of the present utility model, for those of ordinary skills, under the prerequisite of not paying creative work, can also obtain according to these accompanying drawings other accompanying drawing.

Fig. 1 is the rfid system structural representation of a kind of measurement of discharge flow velocity of the utility model embodiment;

Fig. 2 is the schematic diagram that the utility model embodiment flow velocity sensor is connected with the 2nd RFID label chip;

Fig. 3 is the equivalent circuit diagram of the utility model embodiment the 2nd RFID label chip inside antenna;

Fig. 4 is the schematic diagram that the utility model embodiment flow velocity sensor, voltage-resistance conversion equipment are connected with the 2nd RFID label chip inside antenna equivalent electrical circuit;

Fig. 5 schematic diagram that to be the utility model embodiment flow velocity sensor directly be connected with the RFID label antenna;

Fig. 6 is the structure key diagram of the utility model embodiment flow velocity sensor;

Fig. 7 is that the utility model embodiment is based on the method flow diagram of the measurement of discharge flow velocity of signal intensity.

Embodiment

Below in conjunction with the accompanying drawing among the utility model embodiment, the technical scheme among the utility model embodiment is clearly and completely described, 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 obtains under the creative work prerequisite, all belong to the scope of the utility model protection.

As shown in Figure 1, rfid system structural representation for a kind of measurement of discharge flow velocity of the utility model embodiment, the rfid system of described measurement of discharge flow velocity comprises: RFID reader 1, a RFID label 2 and the 2nd RFID label 3, and a described RFID label 2 has identical chip and antenna with described the 2nd RFID label 3; A described RFID label 2 is placed under certain flow velocity level, and the first resonant frequency and the signal intensity of the antenna of a described RFID label 2 remain unchanged, and this moment, a described RFID label 2 was operated under the first resonant frequency; Described the 2nd RFID label 3 is the RFID label with the flow velocity sensor, the antenna of described flow velocity sensor and described the 2nd RFID label 3 forms parallel-connection structure, the circuit that is connected with the chip of the 2nd RFID label at the flow velocity sensor has one voltage-resistance conversion equipment, the circuit of this connection and this voltage-resistance conversion equipment are the parts of chip, the variation of extraneous flow velocity can cause the variation of flow velocity sensor both end voltage or electric current, this moment, described the 2nd RFID label was placed under certain flow velocity level, the characteristic frequency of the antenna of described the 2nd RFID label 3 and signal intensity have at least one and change, and this moment, described the 2nd RFID label 3 was operated under the second resonant frequency; A described RFID label 2 and described the 2nd RFID label 3 receive respectively instruction and the feedback signal that described RFID reader 1 sends, and described RFID reader 1 is by relatively detecting the change of flow velocity from the difference between the signal intensity of a described RFID label 2 and described the 2nd RFID label 3 different frequencies.The flow velocity sensor of the utility model embodiment links to each other with the chip of the 2nd RFID label and has at least three kinds of situations:

The two pins structure:

The utility model embodiment is a kind of rfid system that flow velocity changes that is used for detecting.This system has comprised two RFID labels: a RFID label and the 2nd RFID label.Two pins are arranged on the chip of the 2nd RFID label, two pins of flow velocity sensor and this link to each other, form parallel-connection structure with antenna, the circuit that is connected with the chip of the 2nd RFID label at the flow velocity sensor has one voltage-resistance conversion equipment, the circuit of this connection and this voltage-resistance conversion equipment are the parts of chip, and the variation of extraneous flow velocity can cause the variation of flow velocity sensor both end voltage or electric current.This moment, described the 2nd RFID label was placed under certain flow velocity level, and the first resonant frequency and the signal intensity of the antenna of a RFID label remain unchanged.The characteristic frequency of the antenna of the 2nd RFID label and signal intensity have at least one and change, and this moment, antenna was operated under the second resonant frequency.The RFID reader can send instruction to label, realizes communication, and the difference in the time of can working by comparison the one RFID label and the 2nd RFID label between the signal intensity of different frequency detects the change of flow velocity.

With regard to an example, this system has comprised a kind of RFID label, and described label comprises a RFID label and the 2nd RFID label, and a RFID label and the 2nd RFID label all only have an antenna.Two pins are arranged on the chip of the 2nd RFID label, and two pins of flow velocity sensor and this link to each other, and form parallel-connection structure with antenna.The circuit that is connected with the chip of the 2nd RFID label at the flow velocity sensor has one voltage-resistance conversion equipment, the circuit of this connection and this voltage-resistance conversion equipment are the parts of chip, the variation of extraneous flow velocity can cause the variation of flow velocity sensor both end voltage or electric current, this moment, described the 2nd RFID label was placed under certain flow velocity level, and the first resonant frequency and the signal intensity of the antenna of a RFID label remain unchanged.The characteristic frequency of the antenna of the 2nd RFID label and signal intensity have at least one and change, and this moment, antenna was operated under the second resonant frequency.The RFID reader can send instruction to label, realizes communication, and the difference in the time of can working by comparison the one RFID label and the 2nd RFID label between the signal intensity of different frequency detects the change of flow velocity.

Or rather, described voltage-resistance conversion equipment comprises: a variable voltage converts the equivalent electrical circuit of variable-resistance device or a ditch type field effect transistor or field effect transistor etc. to, and described flow velocity sensor comprises: vortex flow pick-up unit, turbine flow pick-up unit, electromagnetic flow pick-up unit, electromagnetic type flow monitor etc.

With regard to another example, this system has comprised two RFID labels: a RFID label and the 2nd RFID label; The one RFID label and the 2nd RFID label have two antennas.Two pins are arranged on the chip of the 2nd RFID label, two pins of flow velocity sensor and this link to each other, form simultaneously parallel-connection structure with two antennas, the circuit that is connected with the chip of the 2nd RFID label at the flow velocity sensor has one voltage-resistance conversion equipment, and the circuit of this connection and this voltage-resistance conversion equipment are the parts of chip.The variation of extraneous flow velocity can cause the variation of flow velocity sensor both end voltage or electric current.The situation that this and the 2nd RFID label only contain an antenna is similar.Be placed under certain flow velocity level this moment, and the first resonant frequency and the signal intensity of the antenna of a RFID label remain unchanged.The characteristic frequency of the antenna of the 2nd RFID label and signal intensity have at least one and change, and this moment, described the 2nd RFID label antenna was operated under the second resonant frequency.The RFID reader can send instruction to label, realizes communication, and the difference in the time of can working by comparison the one RFID label and the 2nd RFID label between the signal intensity of different frequency detects the change of flow velocity.Or rather, described voltage-resistance conversion equipment comprises: a variable voltage converts the equivalent electrical circuit of variable-resistance device or a ditch type field effect transistor or field effect transistor etc. to, and described flow velocity sensor comprises: vortex flow pick-up unit, turbine flow pick-up unit, electromagnetic flow pick-up unit, electromagnetic type flow monitor etc.

One pin configuration:

This system has comprised two RFID labels: a RFID label and the 2nd RFID label, a pin is arranged on the chip of the 2nd RFID label, this pin outwards links to each other with an end of flow velocity sensor, and the other end of flow velocity sensor 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 the sky line parallel.The circuit that is connected with the chip of the 2nd RFID label at the flow velocity sensor has one voltage-resistance conversion equipment, the circuit of this connection and this voltage-resistance conversion equipment are the parts of chip, and the variation of extraneous flow velocity can cause the variation of flow velocity sensor both end voltage or electric current.Be placed under certain flow velocity level this moment, and the first resonant frequency and the signal intensity of the antenna of a RFID label remain unchanged.The characteristic frequency of the antenna of the 2nd RFID label and signal intensity have at least one and change, and this moment, described the 2nd RFID label antenna was operated under the second resonant frequency.The RFID reader can send instruction to label, realizes communication, and the difference in the time of can working by comparison the one RFID label and the 2nd RFID label between the signal intensity of different frequency detects the change of flow velocity.

With regard to an example, this system has comprised two RFID labels: a RFID label and the 2nd RFID label; The one RFID label and the 2nd RFID label all only have an antenna.A pin is arranged on the chip of the 2nd RFID label, the flow velocity sensor links to each other with this pin, the flow velocity sensor other end is directly linked on the antenna, form parallel-connection structure with antenna, the circuit that is connected with the chip of the 2nd RFID label at the flow velocity sensor has one voltage-resistance conversion equipment, and the circuit of this connection and this voltage-resistance conversion equipment are the parts of chip.The variation of extraneous flow velocity can cause the variation of flow velocity sensor both end voltage or electric current.Be placed under certain flow velocity level this moment, and the first resonant frequency and the signal intensity of the antenna of a RFID label remain unchanged.The characteristic frequency of the antenna of the 2nd RFID label and signal intensity have at least one and change, and this moment, described the 2nd RFID label antenna was operated under the second resonant frequency.The RFID reader can send instruction to label, realizes communication, and the difference in the time of can working by comparison the one RFID label and the 2nd RFID label between the signal intensity of different frequency detects the change of flow velocity.Or rather, described voltage-resistance conversion equipment comprises: a variable voltage converts the equivalent electrical circuit of variable-resistance device or a ditch type field effect transistor or field effect transistor etc. to, and described flow velocity sensor comprises: vortex flow pick-up unit, turbine flow pick-up unit, electromagnetic flow pick-up unit, electromagnetic type flow monitor etc.

Without pin configuration:

This system has comprised two RFID labels: a RFID label and the 2nd RFID label, there is not pin on the chip of the 2nd RFID label, and the flow velocity sensor is directly linked on the antenna.In this case, the antenna that links to each other with the flow velocity sensor can not break away from the flow velocity sensor and with normal frequency for communication.When being placed under certain flow velocity level, the characteristic frequency of antenna and signal intensity have at least one and change.The RFID reader can send instruction to label apparatus, realizes communication, detects the change of flow velocity from the difference between the signal intensity of the different frequency of a RFID label and the 2nd RFID label by comparison.

With regard to an example, this system has comprised two RFID labels: a RFID label and the 2nd RFID label; The one RFID label and the 2nd RFID label all only have an antenna.There is not pin on the chip of the 2nd RFID label, the flow velocity sensor is directly linked on the antenna, the circuit that is connected with the chip of the 2nd RFID label at the flow velocity sensor has one voltage-resistance conversion equipment, and the circuit of this connection and this voltage-resistance conversion equipment are the parts of chip.The variation of extraneous flow velocity can cause the variation of flow velocity sensor both end voltage or electric current.Be placed under certain flow velocity level this moment, and the first resonant frequency and the signal intensity of the antenna of a RFID label remain unchanged.The characteristic frequency of the antenna of the 2nd RFID label and signal intensity have at least one and change, and this moment, described the 2nd RFID label antenna was operated under the second resonant frequency.The RFID reader can send instruction to label, and the difference between the signal intensity of the different frequency during by relatively a RFID label and second label work can detect the change of flow velocity.Or rather, described voltage-resistance conversion equipment comprises: a variable voltage converts the equivalent electrical circuit of variable-resistance device or a ditch type field effect transistor or field effect transistor etc. to, and described flow velocity sensor comprises: vortex flow pick-up unit, turbine flow pick-up unit, electromagnetic flow pick-up unit, electromagnetic type flow monitor 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 accordingly one or more flow velocity sensors, the model of flow velocity sensor can be the same or different simultaneously.With regard to a kind of instantiation of device, when being placed on certain flow velocity after lower a period of time of level, the characteristic frequency of the antenna that links to each other with the flow velocity sensor and signal intensity have at least a meeting to change.The RFID reader can send instruction to label apparatus, detects the change of flow velocity from the difference between the signal intensity of the different frequency of antenna by comparison.

With regard to a kind of instantiation of flow velocity sensor, the method for simultaneous comparison numerical value comprises that the signal strength values with these comparison numerical value and majority compares.These signal strength values belong to different frequencies, and interrelate with the flow velocity value of majority, simultaneously based on the above-mentioned level that relatively can detect flow velocity of mentioning.

Yet with regard to another aspect, a rfid system comprises two RFID label apparatus and a RFID reader device.These two RFID label apparatus are used to send two kinds of signals, namely, the signal of the signal of the one RFID label and the 2nd RFID label, reader is received respectively the signal of a RFID label and the signal of the 2nd RFID label, through the fiducial value between the signal strength values of a RFID label of background process and the 2nd RFID label, and these fiducial values are converted into the varying level of flow velocity.

Again on the one hand, the embodiment of the invention provides a kind of method of rfid system measurement of discharge flow velocity of measurement of discharge flow velocity, described method is applied to the rfid system of above-mentioned measurement of discharge flow velocity, comprise: a described RFID label is placed under certain flow velocity level, the first resonant frequency and the signal intensity of the antenna of a described RFID label remain unchanged, this moment, a described RFID label was operated under the first resonant frequency: described the 2nd RFID label is placed under certain flow velocity level, the characteristic frequency of the antenna of described the 2nd RFID label and signal intensity have at least one and change, and this moment, described the 2nd RFID label was operated under the second resonant frequency; Send instruction to a described RFID label and described the 2nd RFID label and receiving feedback signals by described RFID reader; Difference when utilizing the work of the more described RFID label of described RFID reader and described the 2nd RFID label between the signal intensity of different frequency detects the change of flow velocity.

The schematic diagram of the responsive label 10 of the flow velocity that is connected with the 2nd RFID label chip for the utility model embodiment flow velocity sensor as shown in Figure 2.Among Fig. 2, 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 flow velocity sensor 14, and these two pins are in parallel with the equivalent electrical circuit of antenna at chip internal.This label can communicate with reader.

In an example, transmitting

terminal

11,12 is made by one or more different low electrical resistant materials, these materials have higher electric conductivity, copper for example, silver, and aluminium, they and the above-mentioned flow velocity sensor of mentioning link to each other by two

pins

16,17 and

antenna

11,12, when

antenna

11,12 are placed on certain flow velocity after lower a period of time of level, and the flow velocity sensor 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, the flow velocity sensor is positioned over certain flow velocity after lower a period of time of level, will cause transmission 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 the certain flow flow velocity environment, and then when reaching certain flow velocity, it will reduce.In another example, the antenna frequencies of setting at the beginning is lower than the antenna frequencies under the certain flow rate level, and it will rise when reaching certain flow velocity level.Can be used for such flow velocity sensor of the present utility model has: vortex flow pick-up unit, turbine flow pick-up unit, electromagnetic flow pick-up unit, electromagnetic type flow monitor etc.

Type based on the flow velocity sensor is different, and the flow velocity level that causes changing may be that a specific flow velocity value also may be a selectively scope of flow velocity value.The length of time must cause the variation of antenna resonance frequency, and antenna quality also can cause different variations.For example, on the antenna with the type of flow velocity sensor can affect the length that changes the antenna resonance frequency required time.

As shown in Figure 3, be the equivalent circuit diagram of a RFID label antenna.When the tag coil antenna enters in the alternating magnetic field that 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 primary coil and the secondary coil of transformer.The resonant tank that is formed by label antenna comprises coil inductance (L), the stray capacitance (C of label antenna as shown in the figure _p) and shunt capacitance (C ₂), its resonance frequency is

C is C in the formula _pAnd C ₂Equivalent capacity in parallel, 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 be at the inner Ferrite Material with high permeability that inserts of tag antenna coil, with the increase mutual induction amount, thus the little problem of compensating coil xsect.

As shown in Figure 4, be the utility model embodiment flow velocity sensor, voltage-resistance conversion equipment and the schematic diagram that is connected with the 2nd RFID label antenna equivalent electrical circuit.The resonant tank that is formed by label antenna comprises coil inductance (L), the stray capacitance (C of label antenna as shown in the figure _p) and shunt capacitance (C ₂), its resonance frequency is

Formula C is C _pAnd C ₂Equivalent capacity in parallel, R ₁, R ₂Equivalent resistance for circuit internal inductance coil and other devices.R3 is the equivalent resistance of connecting with the flow velocity sensor, and F is voltage-resistance conversion equipment.M is the variable resistor of representative flow velocity sensor.This label is placed under certain flow velocity level, and its characteristic frequency and signal intensity have at least one and change, and antenna is operated under the second resonant frequency.

As shown in Figure 5, can detect the sketch of the passive RFID tags device 40 of flow velocity 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 flow velocity sensor 44 that links to each other with antenna 42 will affect the resistance of antenna 42.The material that flow velocity sensor 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 example, fixing up an aerial wire 41,42 can make it produce resonance in identical frequency.With regard to another example, 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 made 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 the above-mentioned flow velocity sensor of mentioning, when antenna 41,42 are placed on certain flow velocity after lower a period of time of level, and the flow velocity sensor 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, the flow velocity sensor is positioned over certain flow velocity after lower a period of time of level, will cause transmission 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 the certain flow flow velocity environment, and then when reaching certain flow velocity, it will reduce.In another example, the antenna frequencies of setting at the beginning is lower than the antenna frequencies under the certain flow rate level, and it will rise when reaching certain flow velocity level.The such flow velocity sensor that can be used for this utility model comprises: vortex flow pick-up unit, turbine flow pick-up unit, electromagnetic flow pick-up unit, electromagnetic type flow monitor etc.

As shown in Figure 6, be the turbine flow pick-up unit.It is by permanent magnet 61,

coil

62, and 63

electrodes

64,65 unshakable in one's determination, impeller 66, bearing 67 and pipeline 68 form.The rotating speed that is placed on the impeller 66 in the fluid by measurement carries out flow rate test.The theory that it utilizes the rotation rotating speed of turbine to be directly proportional with flow.When impeller 66 places fluid, because the fluoran stream surface of blade is different with the lee side flow velocity, therefore flowing to direction formation pressure reduction, because making, the reasoning that pressure reduction produces revolves the oar rotation.If select the little bearing of friction force to support impeller, and impeller adopts lightweight material to make, as long as then can make the relation of flow velocity and rotating speed approach the rotating speed that linearity records impeller, just know the speed of fluid.

As shown in Figure 7, be the method flow diagram of the utility model embodiment based on the measurement of discharge flow velocity of signal intensity, described method is applied to the rfid system of above-mentioned measurement of discharge flow velocity, comprising:

701, a described RFID label is placed under certain flow velocity level, the first resonant frequency and the signal intensity of the antenna of a described RFID label remain unchanged, and this moment, a described RFID label was operated under the first resonant frequency:

702, described the 2nd RFID label is placed under certain flow velocity level, the characteristic frequency of the antenna of described the 2nd RFID label and signal intensity have at least one and change, and this moment, described the 2nd RFID label was operated under the second resonant frequency;

703, send instruction to a described RFID label and described the 2nd RFID label and receiving feedback signals by described RFID reader;

Difference when 704, utilizing the work of the more described RFID label of described RFID reader and described the 2nd RFID label between the signal intensity of different frequency detects the change of flow velocity.

The RFID reader can be measured the energy intensity of receiving signal, calculates the fiducial value of a reaction signal intensity, then fiducial value is changed into different flow velocity values.With regard to an example, 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, the RFID reader will from the signal strength values of a RFID label that does not link to each other with the flow velocity sensor as a reference value, compare its signal strength values with the 2nd RFID label that links to each other with the flow velocity sensor.By receive from linking to each other with the flow velocity sensor and a RFID label that does not link to each other with the flow velocity sensor and the signal of the 2nd RFID label, the RFID reader can be collected the fiducial value that represents unlike signal intensity.Then, the RFID reader can be converted into the residing flow velocity level of label to such fiducial value.With regard to a concrete example, configure this RFID reader and be for by use that the reference data that stores will receive from connect or not the difference of the RF signal intensity of the RFID label of connection traffic flow velocity sensor be converted into the flow velocity value.

Best situation is, a RFID label of connection traffic flow velocity sensor not as a reference, can be filtered out the variation that causes owing to the coupling between label and the reader.In addition, just as previously mentioned, the flow velocity sensor is applied to the time length that the variation of the resistance value that can make it in the design and the 2nd RFID label be placed under the particular flow rate flow velocity and forms one to one relation.The same, by using the utility model, under the passive condition of RFID label, the RFID reader can detect label apparatus whether be placed under certain flow velocity and this flow velocity whether within the acceptable range.

Also can not perceive with the flow velocity sensor variation of flow velocity with the various RFID labels of two antennas, the variation that the variation of perceived flux flow velocity is based on resonant frequency on the antenna also can recognize antenna reception to the variation of signal.

For example pass through the design to the antenna that links to each other with the flow velocity sensor, can make the frequency of antenna 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 flow velocity sensor and logical circuit on the label of standard.

For example label antenna can so be set in a concrete example, before in being exposed to certain flow flow velocity environment, the resonant frequency of antenna is 902-928MHZ, but in a single day label is exposed in the certain flow flow velocity environment, because the impact of flow velocity, 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, the channel that can not receive of skipping that reader can be random in these 52 channels goes, 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 the flow velocity sensor, so as long as flow velocity 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 just no longer allows label to carry out exchanging of information with channel n.

In concrete example, if the environment at label place has surpassed the flow velocity scope of expection, reader can only send instruction to label by channel 1 to n-1, label also can be made a response, because the antenna in the label just can only be worked in this frequency range, when reader sends instruction with the frequency of n channel to label, so no longer reach the 928MHZ label and just no longer make a response because the variation of label flow velocity has caused the resonant frequency of label antenna to drop to 899.5-9275MHZ, pass information back reader.

Favourable aspect is just to be reflected by the disappearance of this information interchange owing to variation that flow velocity 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 check that further drift has occured the operating frequency range of label antenna, because label can receive the instruction that sends by channel n-1, and can be to the reader feedback information by channel n-1, because label can not receive the instruction that sends by channel n, and can not can to the reader feedback information, so just determine that drift has occured the operating frequency range of label antenna by channel n.

Drift and present utility model that the variation of flow velocity causes the frequency of operation of label antenna to occur up and down are not limited in frequency range on average are divided into n channel.

The utility model embodiment can detect flow velocity at lower cost to be changed, and the energy that utilizes RFID to obtain, and has solved the powerup issue that flow velocity detects.

The enforcement of each characteristics of this system may relate to software, the combination that hardware also may 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 OO programming language with a kind of high-caliber processing by programming.Each such function program may be stored in the storage intermediary and for example be read to realize above-mentioned function by a computer and processor in the ROM (read-only memory).

Those skilled in the art can also recognize the various illustrative components, blocks (illustrative logical block) that the utility model embodiment lists, the unit, and step can pass 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 specific application and whole system by hardware or software.Those skilled in the art can be for every kind of specific application, and can make ins all sorts of ways realizes described function, but this realization should not be understood 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 by the combination of calculation element, for example digital signal processor and microprocessor, multi-microprocessor, Digital Signal Processor Core of one or more microprocessors associatings, or any other similarly configuration realize.

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 be from storage medium reading information, 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 different 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 realize in software, these functions can be stored on the medium with computer-readable, or are transmitted on the medium of computer-readable with one or more instructions or code form.The computer-readable medium comprises the computer storage medium and is convenient to so that allow computer program transfer to other local telecommunication media from a place.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 anyly can be used for carrying or storage can be read by general or special computer or general or special processor the program code of form with instruction or data structure and other medium.In addition, any connection can suitably be defined as the computer-readable medium, for example, if software is by a concentric cable, optical fiber computer, twisted-pair feeder, Digital Subscriber Line (DSL) or also being comprised in the defined computer-readable medium with wireless way for transmittings such as infrared, wireless and microwave 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 medium.

Above-described embodiment; the purpose of this utility model, technical scheme and beneficial effect are further described; institute is understood that; the above only is embodiment of the present utility model; and be not used in and limit protection domain of the present utility model; all within spirit of the present utility model and principle, any modification of making, be equal to replacement, improvement etc., all should be included within the protection domain of the present utility model.

Claims

1. the rfid system of a measurement of discharge flow velocity, it is characterized in that, the rfid system of described measurement of discharge flow velocity comprises: RFID reader, a RFID label and the 2nd RFID label, and a described RFID label has identical chip and antenna with described the 2nd RFID label; A described RFID label is placed under certain flow velocity level, and the first resonant frequency and the signal intensity of the antenna of a described RFID label remain unchanged, and this moment, a described RFID label was operated under the first resonant frequency; Described the 2nd RFID label is the RFID label with the flow velocity sensor, and two pins are arranged on the chip of described the 2nd RFID label; Two pins of described flow velocity sensor and this link to each other, and form parallel-connection structure with the antenna of described the 2nd RFID label, the circuit that is connected with the chip of the 2nd RFID label at the flow velocity sensor has one voltage-resistance conversion equipment, the circuit of this connection and this voltage-resistance conversion equipment are the parts of chip, the variation of extraneous flow velocity can cause the variation of flow velocity sensor both end voltage or electric current, this moment, described the 2nd RFID label was placed under certain flow velocity level, the characteristic frequency of the antenna of described the 2nd RFID label and signal intensity have at least one and change, and this moment, described the 2nd RFID label was operated under the second resonant frequency; A described RFID label and described the 2nd RFID label receive respectively instruction and the feedback signal that described RFID reader sends, and described RFID reader is by relatively detecting the change of flow velocity from the difference between the signal intensity of a described RFID label and described the 2nd RFID label different frequency.

2. the rfid system of measurement of discharge flow velocity as claimed in claim 1, it is characterized in that, the antenna of a described RFID label and described the 2nd RFID label is monopole antenna: the antenna of described flow velocity sensor and described the 2nd RFID label forms parallel-connection structure.

3. the rfid system of measurement of discharge flow velocity as claimed in claim 1, it is characterized in that, the antenna of a described RFID label and described the 2nd RFID label is double-doublet antenna: an antenna of described flow velocity sensor and described the 2nd RFID label forms parallel-connection structure, perhaps forms simultaneously parallel-connection structure with two antennas.

4. the rfid system of a measurement of discharge flow velocity, it is characterized in that, the rfid system of described measurement of discharge flow velocity comprises: RFID reader, a RFID label and the 2nd RFID label, and a described RFID label has identical chip and antenna with described the 2nd RFID label; A described RFID label is placed under certain flow velocity level, and the first resonant frequency and the signal intensity of the antenna of a described RFID label remain unchanged, and this moment, a described RFID label was operated under the first resonant frequency; Described the 2nd RFID label is the RFID label with the flow velocity sensor, and a pin is arranged on the chip of described the 2nd RFID label; One end of described flow velocity sensor links to each other with this pin, the other end is connected on the antenna of described RFID label, and form parallel-connection structure with antenna, the circuit that is connected with the chip of the 2nd RFID label at the flow velocity sensor has one voltage-resistance conversion equipment, the circuit of this connection and this voltage-resistance conversion equipment are the parts of chip, the variation of extraneous flow velocity can cause the variation of flow velocity sensor both end voltage or electric current, this moment, described the 2nd RFID label was placed under certain flow velocity level, the characteristic frequency of the antenna of described the 2nd RFID label and signal intensity have at least one and change, and this moment, described the 2nd RFID label was operated under the second resonant frequency; A described RFID label and described the 2nd RFID label receive respectively instruction and the feedback signal that described RFID reader sends, and described RFID reader is by relatively detecting the change of flow velocity from the difference between the signal intensity of a described RFID label and described the 2nd RFID label different frequency.

5. the rfid system of measurement of discharge flow velocity as claimed in claim 4, it is characterized in that, the antenna of a described RFID label and described the 2nd RFID label is monopole antenna: the antenna of described flow velocity sensor and described the 2nd RFID label forms parallel-connection structure.

6. the rfid system of measurement of discharge flow velocity as claimed in claim 4, it is characterized in that, the antenna of a described RFID label and described the 2nd RFID label is double-doublet antenna: an antenna of described flow velocity sensor and described the 2nd RFID label forms parallel-connection structure, perhaps forms simultaneously parallel-connection structure with two antennas.

7. the rfid system of a measurement of discharge flow velocity, it is characterized in that, the rfid system of described measurement of discharge flow velocity comprises: RFID reader, a RFID label and the 2nd RFID label, and a described RFID label has identical chip and antenna with described the 2nd RFID label; A described RFID label is placed under certain flow velocity level, and the first resonant frequency and the signal intensity of the antenna of a described RFID label remain unchanged, and this moment, a described RFID label was operated under the first resonant frequency; Described the 2nd RFID label is the RFID label with the flow velocity sensor, described flow velocity sensor is connected on the antenna of described RFID label, and form parallel-connection structure with antenna, the circuit that is connected with the chip of the 2nd RFID label at the flow velocity sensor has one voltage-resistance conversion equipment, the circuit of this connection and this voltage-resistance conversion equipment are the parts of chip, the variation of extraneous flow velocity can cause the variation of flow velocity sensor both end voltage or electric current, this moment, described the 2nd RFID label was placed under certain flow velocity level, the characteristic frequency of the antenna of described the 2nd RFID label and signal intensity have at least one and change, and this moment, described the 2nd RFID label was operated under the second resonant frequency; A described RFID label and described the 2nd RFID label receive respectively instruction and the feedback signal that described RFID reader sends, and described RFID reader is by relatively detecting the change of flow velocity from the difference between the signal intensity of a described RFID label and described the 2nd RFID label different frequency.

8. the rfid system of measurement of discharge flow velocity as claimed in claim 7, it is characterized in that, the antenna of a described RFID label and described the 2nd RFID label is monopole antenna: the antenna of described flow velocity sensor and described the 2nd RFID label forms parallel-connection structure.

9. the rfid system of measurement of discharge flow velocity as claimed in claim 7, it is characterized in that, the antenna of a described RFID label and described the 2nd RFID label is double-doublet antenna: an antenna of described flow velocity sensor and described the 2nd RFID label forms parallel-connection structure, perhaps forms simultaneously parallel-connection structure with two antennas.