Classification And Application
At present the definition of the operating frequency of the low - frequency RFID products, both HF and VHF frequency ranges within which conform to different standards of different products, but is different from the frequency band of RFID products will have different characteristics in which the inductor is a passive At present the definition of the operating frequency of the low - frequency RFID products, both HF and VHF frequency ranges within which conform to different standards of different products, but is different from the frequency band of RFID products will have different characteristics in which the inductor is a passive . and and .
active in two ways active in two ways.
Low Frequency
low frequency (from 125 KHz to 134 KHz) actually obtained in the first low frequency RFID technology possesses the vast low frequency (from 125 KHz to 134 KHz) actually obtained in the first low frequency RFID technology possesses the vast . which is a frequency that is mostly in an inductive manner, i.e. to the coil and the inductor coil in the reader / writer existing between the transformer 9 coupling
by alternating field of the reader / writer antenna in the same manner as that of the inductor in the induction voltage is rectified in the rectifier, can be used as power supply voltage. The magnetic field region can be defined, but the field strength drops too fast characteristics:operation at a low frequency of the inductor generally operates at a frequency of 120 KHz to 134 KHz from, TI's operating frequency is 2 KHz characteristics:operation at a low frequency of the inductor generally operates at a frequency of 120 KHz to 134 KHz from, TI's operating frequency is 2 KHz .
this band of wavelength of about 2500m;1. in addition to the influence of a metallic material, a low frequency can pass through any material that does not reduce its read distance. The working frequency of the reader - writer in the world, with no special restriction is 3. The outputs of the first and second products in different packaging in the form of a package form is
a good price, but there is more than 10 years of service life a good price, but there is more than 10 years of service life . 4. While the frequency of the magnetic field decreases very quickly, but can generate a relatively uniform region of read and write
5. with respect to the other frequency band of RFID products, which are very slow data transmission rate 6. the price of the inductor with other bands for more expensive
main applications:animal husbandry management system;Automobile antitheft and no key in the application of the system;Marathon (application of the system;Automatic parking and vehicle management system;Automatic oiling system of the application;hotel door lock system of the application;entrance guard safety management system and main applications:animal husbandry management system;Automobile antitheft and no key in the application of the system;Marathon (application of the system;Automatic parking and vehicle management system;Automatic oiling system of the application;hotel door lock system of the application;entrance guard safety management system and .
High Frequency
the operating frequency of the high frequency (13.56 MHz) at the frequency of the inductor coil is no longer necessary, and manufacturing, and can eat through alive by printing, for making the antenna inductor generally via load modulation operates inductor generally via load modulation operates .
is via the inductor on the load resistance on and off of the reader / writer antenna causing a change of voltage on the inductor is realized with the antenna voltage to amplitude - modulate a is via the inductor on the load resistance on and off of the reader / writer antenna causing a change of voltage on the inductor is realized with the antenna voltage to amplitude - modulate a . If people use data to control the load voltage to be switched on and off, then these data can be transmitted from the sensor to the reader / writer If people use data to control the load voltage to be switched on and off, then these data can be transmitted from the sensor to the reader / writer .
characteristics: 1. the operating frequency of 13.56 mhz,The frequency of the wavelength of approximately 22m.2. In addition to the metal materials, the frequency of the wavelength can pass through most of the material, but tends to reduce the read distance is a distance away from the metal sensor needs ;3. The band in the world were recognized and there is no special limitation.4. The inductor, generally in the form of the electronic tag;5. While the frequency of the magnetic field decreases very quickly, but can generate a relatively uniform region of read and write;6. The system has the characteristics of impact, it is possible to simultaneously read a plurality of electronic tag;7. Let f (x) is written in the tag data information;8. The data transmission rate faster than that of the low prices that you're not a very expensive
main applications: Application of Book Management System;LPG cylinder management application;Clothing line and logistics system of management and application;Three meter precharging system;Hotel management and application;in all of the major channels of the system;fixed assets management system;Pharmaceutical Logistics System of Management and the Application;Intelligent shelf management main applications: Application of Book Management System;LPG cylinder management application;Clothing line and logistics system of management and application;Three meter precharging system;Hotel management and application;in all of the major channels of the system;fixed assets management system;Pharmaceutical Logistics System of Management and the Application;Intelligent shelf management .
VHF
VHF frequency (860 MHz to 960 MHz VHF system by the electric field between the transmission energy of the electric field energy drop VHF frequency (860 MHz to 960 MHz VHF system by the electric field between the transmission energy of the electric field energy drop . not soon, but the read area is not well defined not soon, but the read area is not well defined .
read this band has a relatively far distance, the passive may be up to about 10m read this band has a relatively far distance, the passive may be up to about 10m . mainly through the capacitance coupling manner realize mainly through the capacitance coupling manner realize .
characteristics: 1. In this band, not the very definition of global same - Europe and parts of Asia to the defined frequency is 868 MHz, 902 MHz for North America for the band, to the plot,In the Japanese proposal of the frequency band from 950 MHz to 956MHz between the wavelength band of approximately 30 cm between the wavelength band of approximately 30 cm .
2. Currently, the band power output in the current definition (defined as U.S. 4W, a European definition of 500mW ) 3. VHF band radio wave cannot pass through many materials, especially water, dust, fog, and suspended particulate materials
with respect to the high frequency electronic label, the band of the electronic tag and without the need for a separate metal to with respect to the high frequency electronic label, the band of the electronic tag and without the need for a separate metal to . 4. The electronic tag of the tag antenna is generally elongated and shaped linearly and circularly polarized antenna
There are two design,meet the requirements of different applications There are two design,meet the requirements of different applications . 5. The band has a good reading of the distance, but the read area is difficult to apply a defined
6. there is a high data transmission rate, in a very short time to read a large number of electronic tag main applications: supply chain management and application;automation of the production line management and the application;air parcel of the management and application;Container management and application;Railway parcel of the management and application;Logistics Management System;large - scale employee exit management application main applications: supply chain management and application;automation of the production line management and the application;air parcel of the management and application;Container management and application;Railway parcel of the management and application;Logistics Management System;large - scale employee exit management application .
Active RFID Technology
Active RFID technology (2.45 GHz, 5.8 GHz) active RFID provided with the low transmit power, the communication distance is long, transmission data amount is large, the reliability is high and the compatibility is good, as compared to a passive RFID, technically advantage to are widely applied to highway toll collection, management of port freight, personnel positioning management applications such as in are widely applied to highway toll collection, management of port freight, personnel positioning management applications such as in .
but using this frequency band has a strong directivity, and the receiving region, e.g., metal objects, metal objects on the frequency band of the RF will produce reflection and refraction, so that the influence of the radio frequency receiver signal write
Work Principle
system of basic work flow is: the reader through the transmit antenna to transmit a certain frequency of the RF signal, RF card when enter working area when the transmit antenna are induced in the core 10, the obtained energy is activated;RF card itself, or the like for the information transmitted by the card in the built - in antenna;system transmission antenna is received from the radio - frequency carrier signal sent by antenna regulator is transmitted to the reader, the reader signal and demodulates and decodes a received signal is then sent to the backend host system to perform the correlation process; andmain logic operation system according to the judgment of the legitimacy of the card, for different corresponding to the setting of the processing and control, an instruction signal to the control action of the actuator in a coupled manner (system of basic work flow is: the reader through the transmit antenna to transmit a certain frequency of the RF signal, RF card when enter working area when the transmit antenna are induced in the core 10, the obtained energy is activated;RF card itself, or the like for the information transmitted by the card in the built - in antenna;system transmission antenna is received from the radio - frequency carrier signal sent by antenna regulator is transmitted to the reader, the reader signal and demodulates and decodes a received signal is then sent to the backend host system to perform the correlation process; andmain logic operation system according to the judgment of the legitimacy of the card, for different corresponding to the setting of the processing and control, an instruction signal to the control action of the actuator in a coupled manner (. - electromagnetic inductance), the communication process (FDX and HDX, SEQ), from the card to the reader of the data transmission method (the load modulation, a backscattering of the high - order harmonic) and frequency range, different non - contact transmission methods differ, but all of the reader functions in principle, as well as design configuration are very similar,All reader can simplify the interface control unit for high frequency and high frequency module of the two basic - electromagnetic inductance), the communication process (FDX and HDX, SEQ), from the card to the reader of the data transmission method (the load modulation, a backscattering of the high - order harmonic) and frequency range, different non - contact transmission methods differ, but all of the reader functions in principle, as well as design configuration are very similar,All reader can simplify the interface control unit for high frequency and high frequency module of the two basic .
interface comprising a transmitter and a receiver, whose functions include: generating a high frequency power and provides energy to activate the RF card;a transmit signal for modulation, for transmitting data to RF card;receiving and demodulating the signal from the radio - frequency signal of high frequency radio frequency identification system interface comprising a transmitter and a receiver, whose functions include: generating a high frequency power and provides energy to activate the RF card;a transmit signal for modulation, for transmitting data to RF card;receiving and demodulating the signal from the radio - frequency signal of high frequency radio frequency identification system . different interface design has some difference different interface design has some difference .
reader function of the control unit includes: performing communication with the application software, and executing the application software from the command;Radio frequency (RF) communication with the control of the process (master - slave principle);the signal codec reader function of the control unit includes: performing communication with the application software, and executing the application software from the command;Radio frequency (RF) communication with the control of the process (master - slave principle);the signal codec . on some particular systems as well as perform algorithms, and RF card reader and used to encrypt and decrypt data transmitted between the reader and the RF card and performs authentication of the additional function for on some particular systems as well as perform algorithms, and RF card reader and used to encrypt and decrypt data transmitted between the reader and the RF card and performs authentication of the additional function for .
wireless radio frequency recognition read - write distance is a very critical parameter wireless radio frequency recognition read - write distance is a very critical parameter . currently, the price of long distance wireless radio frequency identification (RFID) systems is also very expensive and are therefore looking to enhance their reading distance is very important method of currently, the price of long distance wireless radio frequency identification (RFID) systems is also very expensive and are therefore looking to enhance their reading distance is very important method of .
influence factors include the distance of the RF antenna operating frequency, the output power of the RF reader, the reader receiver sensitivity, power consumption of the RF card, the antenna and the Q value of the resonance circuit, the antenna direction,and the degree of coupling of the RF card reader, the card itself and the obtained energy of the energy and can be used such as influence factors include the distance of the RF antenna operating frequency, the output power of the RF reader, the reader receiver sensitivity, power consumption of the RF card, the antenna and the Q value of the resonance circuit, the antenna direction,and the degree of coupling of the RF card reader, the card itself and the obtained energy of the energy and can be used such as . most system of reading and writing distance distance is different, writes the read distance is a distance of about 40% ~ 80% most system of reading and writing distance distance is different, writes the read distance is a distance of about 40% ~ 80% .
Units Of Account
Absolute Power
The various radio frequencies are commonly used in the unit of account, which is the in - depth understanding of the concept of essential basic knowledge of one of the radio frequency;absolute power of the RF signal in dB, of the absolute power of the common dBm, dBW, mW, W. The conversion of the following: e.g. signal power of x, w, expressed in dBm when its size is equal to 1 mW 0 dBm, for example: equal to 30 dBm (1W), equal to odbw 0 dBm, for example: equal to 30 dBm (1W), equal to odbw .
Relative Power
relative power in dB, of the radio frequency signals with respect to the common power dB and dBc in both, with the difference that: any two dB is the power of the logarithm of the ratio of the said form;while the dBc is a carrier frequency output power and output power of the logarithm of the ratio expressed for example in the form relative power in dB, of the radio frequency signals with respect to the common power dB and dBc in both, with the difference that: any two dB is the power of the logarithm of the ratio of the said form;while the dBc is a carrier frequency output power and output power of the logarithm of the ratio expressed for example in the form .: dBm - 30 dB = 0 dBm: dBm - 30 dB = 0 dBm.
Antenna Gain
The antenna gain in dBi or generally by dBd represents The antenna gain in dBi or generally by dBd represents . dBi antenna is free with respect to the direction of the antenna of the power and energy density, dBd) indicates that the dipole antenna, a dipole, the power level of the energy density, the ratio of the dipole antenna has a gain of 2. 15dBi, 0dBd = 2. 15dBi
Other Units Of The People's Republic Of China
resistance: a current is blocked by an object or substance, thereby converting electrical energy into thermal energy or other forms of energy, the unit: ohm, 1 ohm voltage potential or a potential difference in volts, V Current: within a unit time by a specified circuit point and the number of charges, in amps, A 6 inductance: that is surrounded by said coil, typically on the wire, due to electromagnetic induction, the coil can generate electromotive force can, in henrys, H capacitor: The ratio of charge to potential on an electrically charged, isolated conductor, in farads, Fresistance: a current is blocked by an object or substance, thereby converting electrical energy into thermal energy or other forms of energy, the unit: ohm, 1 ohm voltage potential or a potential difference in volts, V Current: within a unit time by a specified circuit point and the number of charges, in amps, A 6 inductance: that is surrounded by said coil, typically on the wire, due to electromagnetic induction, the coil can generate electromotive force can, in henrys, H capacitor: The ratio of charge to potential on an electrically charged, isolated conductor, in farads, F.
The Term Knowledge
1. / power level (dBm), in which the amplifier's output capacity, typically in units of w, mw, dBm2. gain (dB): i.e. the magnification, the unit may be expressed as a decibel (dB) Note: 1mw dBm is taken as the reference value, expressed in decibels, of the absolute power level of the Note: 1mw dBm is taken as the reference value, expressed in decibels, of the absolute power level of the .
Formula: level (dBm) = 10lgmw5W 10lg5000 37dBm10W? =? =? = 10lg10000 40dBm20W 10lg20000 dBm from on the show, the power for every doubling of the level value is increased by 3 dB, i.e.:dB = 10lgA (A) for the amplification multiple of 3. Insertion loss: when a particular device or component to access the transmission circuit of the increase of the attenuation, expressed in dB 4. Selectivity is a measure of the change in the operating band of the gain and the out - of - band radiation suppression capability
-3 dB bandwidth of the gain drops by 3 dB bandwidth, 40 dB, -60 dB -3 dB bandwidth of the gain drops by 3 dB bandwidth, 40 dB, -60 dB . 5 Similarly. return loss (VSWR): moving standing wave state, a voltage antinode and node of the voltage ratio (VSWR): SWR return loss comparison table: SWR1, 1.2, 1.25, 1.30, 1.35, 1.40,1. 50 a return loss (dB) 21, 19, 17. 6, 16, 15. 6, and 14. 0 Note: return loss (RL) according to the calculation of the standing wave ratio (SWR) satisfy the relation SWR = 10 ^ (20 + 1 / RL) / RL / 10 ^ (20 - 1)
6. - 2: If there are two sinusoidal signals. omega.1 and. omega.2 due to nonlinear effects caused by the intermodulation component, wherein the 2 - 1 and 1 - 2 2 omega (. omega.) of the two frequency components are referred to as third order intermodulation product,its power P3 signal. omega.1 and. omega.2 for the power or the ratio of said third coefficient of the M3 / M3 = 10lgP3 i.e. P1 (dBc) 7. Noise Figure: generally defined as the output signal - to - noise ratio (SNR) of the input signal to noise ratio, the ratio of the actual use is calculated in decibels dB
. 8. Coupling: The coupling ports and input ports, and the power ratio in dB
9. and the isolation of the local oscillator or signal leakage to the other port of the original power - to - power ratio, in units of dB 10. antenna gain (dB):antenna means to transmit power to be reduced to a specified direction of the concentrated radiation capacity
generally of the antenna to the maximum radiation direction of the electric field strength E and the ideal isotropic antenna radiates uniformly by using intensity E0, to increase the power density is defined as a multiple of the gain Ga generally of the antenna to the maximum radiation direction of the electric field strength E and the ideal isotropic antenna radiates uniformly by using intensity E0, to increase the power density is defined as a multiple of the gain Ga . E02 = E2 / 3 11. antenna direction FIG.: is the antenna radiating the electromagnetic waves in free space is present in the range of the width direction of the FIG.
generally means the mainlobe width from the maximum value is reduced by one - half of the angle points Zhang generally means the mainlobe width from the maximum value is reduced by one - half of the angle points Zhang . 12. The antenna front to back ratio (FBR): means the maximum forward gain and a maximum reverse ratio of a gain, expressed in decibels (db)
13. simplex: Also referred to as single frequency simplex,i.e. the transmission and reception using the same frequency, since the receive and transmit using the same frequency, the transmission and reception cannot be performed simultaneously, called a simplex 14. duplex: Also referred to as inter - frequency diplex system, i.e. the transmission and reception using the two different frequencies, either in the utterance of the simultaneously received each
simplex, duplex, both belonging to the mobile communication function in such a manner that the simplex, duplex, both belonging to the mobile communication function in such a manner that the . 15. amplifiers (SSPAs) for realizing the signal amplification circuit
16. Filter: the filter) by the useful frequency signal to reject the undesired signal frequency component or device 17. The attenuator:an attenuator (4) over a wide frequency band range of phase shift is zero, the characteristic impedance and its attenuation with frequency - independent constant by a resistive element composed of the four - terminal network, its main purpose is to adjust the size of the circuit in the signal, an improved impedance match power divider : : .
device distributes the power of two, three, four power divider;N - type connector heads (50 ohm), SMA (50 ohm), and F - head (75 omega) 18. coupler: from the trunk passage in the extracted signal portion of the device according to the degree of coupling to the size of
5. 10. 15. 20 dB different specifications;high pow available from the base station extracts the signal coupler (300 W), from which the degree of coupling is selected in 30 ~ 65dB;The coupling of the joint using multi - head N 5 19. load: terminal in a circuit, such as an amplifier or an electrical output port, the reception electric power of the element / device, or components, which are collectively referred to as a load on the load
basic requirement is that the impedance matching and to be able to withstand the power of the basic requirement is that the impedance matching and to be able to withstand the power of the . 20. annular holder: the signal transmission device of single direction
21. joint: the different types of transmission line coupling together 22. Feeder: is a high frequency current of transmission line
23. The antenna:(antenna) is a high - frequency current or the waveguide in the form of waves into electromagnetic energy and to a predetermined direction is transmitted or from a certain direction of the electromagnetic wave obtained by the reduction of the high frequency current
Application Field
Communication System
In the entire radio communication frequency is introduced, mainly including the following frequency: the frequency of the transmission 7, the receiving frequency, intermediate frequency and baseband frequency to a baseband frequency In the entire radio communication frequency is introduced, mainly including the following frequency: the frequency of the transmission 7, the receiving frequency, intermediate frequency and baseband frequency to a baseband frequency . is used to modulate the data signal of the frequency of the transmission while is used to modulate the data signal of the frequency of the transmission while .
true than those frequencies in the baseband, i.e. the share of the spectrum is the range 500 MHz to GHz, the data signal is also at that high frequency for transmission of the In general, a radio frequency system has a very strong modulation of the transmission signal of the function, even if the interfering signal and the blocking signal z2,The system may also be needed to be taken to ensure the highest quality and the best receiving sensitivity modulation signal In general, a radio frequency system has a very strong modulation of the transmission signal of the function, even if the interfering signal and the blocking signal z2,The system may also be needed to be taken to ensure the highest quality and the best receiving sensitivity modulation signal .
blocking signal can be divided into two categories: in - band blocking signal and the out - of - band blocking signal blocking signal can be divided into two categories: in - band blocking signal and the out - of - band blocking signal . out - of - band blocking signal means a signal outside the frequency spectrum regardless of the signal, e.g. by the other radio signal of the data signal generated by the in - band blocking signal
is in our interest to which the spectrum of the signal within, for example by the same wireless technology on the is in our interest to which the spectrum of the signal within, for example by the same wireless technology on the . data signals generated by other terminals for wireless communication, to successfully implement a radio frequency receiving function,must filter out both low - frequency blocking signal data signals generated by other terminals for wireless communication, to successfully implement a radio frequency receiving function,must filter out both low - frequency blocking signal .
is used as a transmitting / receiving frequency and baseband frequency transition, which is a superheterodyne structure. On the basis of the In general, the out - of - band blocking signal may be an antenna with a filter to filter out In general, the out - of - band blocking signal may be an antenna with a filter to filter out .
while the intermediate - frequency there is an opportunity to signal is mixed into the baseband and digital prior to processing by the in - band blocker signal filtering while the intermediate - frequency there is an opportunity to signal is mixed into the baseband and digital prior to processing by the in - band blocker signal filtering . on the other hand, at the transmitting end,IF is used to attain all from baseband to an intermediate frequency and that of the dummy data and noise on the other hand, at the transmitting end,IF is used to attain all from baseband to an intermediate frequency and that of the dummy data and noise .
adopt a superheterodyne structure of another kind of realization method is sampled in intermediate frequency.Sampling of IF signals to reduce the number of devices in the chain chosen in this way in the intermediate frequency signal is being sampled, rather than in the sample before the signal is mixed into the baseband chosen in this way in the intermediate frequency signal is being sampled, rather than in the sample before the signal is mixed into the baseband .
In the first superheterodyne structure, from the intermediate frequency to baseband conversion process requires the following device: This machine is a phase - locked loop, the intelligent demodulator (mixer) and bi - directional analog - digital converter (ADC) In the first superheterodyne structure, from the intermediate frequency to baseband conversion process requires the following device: This machine is a phase - locked loop, the intelligent demodulator (mixer) and bi - directional analog - digital converter (ADC) . if selected in the IF sampling,That these three devices may be a high performance of the ADC in place of if selected in the IF sampling,That these three devices may be a high performance of the ADC in place of .
. This not only can reduce the complexity of the signal chain, it is also possible to improve the quality of the demodulated signal but, if the downlink baseband demodulator converter in the application of a high quality intelligent, also can have extremely good communication effect but, if the downlink baseband demodulator converter in the application of a high quality intelligent, also can have extremely good communication effect .
if you can make the local phase - locked loop and the RF device leakage is sufficiently small, the baseband DC offset is minimized as well if you can make the local phase - locked loop and the RF device leakage is sufficiently small, the baseband DC offset is minimized as well . In addition, the demodulator of the phase separation function can be at a highly accurate 90 degree of phase separation, which would ensure that the demodulated signal, the error vector of values which will not deteriorate or just a little worse last In addition, the demodulator of the phase separation function can be at a highly accurate 90 degree of phase separation, which would ensure that the demodulated signal, the error vector of values which will not deteriorate or just a little worse last .
,If we use the intelligence of the demodulator at the same time, using one having a low phase noise, will ensure the baseband output signal of the low - noise, and thus obtain a good bit error rate (BER) ,If we use the intelligence of the demodulator at the same time, using one having a low phase noise, will ensure the baseband output signal of the low - noise, and thus obtain a good bit error rate (BER) . because ADC will continue at higher frequency, the IF sampling structure of the power consumption becomes smaller than that of the first superheterodyne structure is becoming higher and higher, and therefore more expensive, which is an IF sampling structure of most of the major disadvantages of because ADC will continue at higher frequency, the IF sampling structure of the power consumption becomes smaller than that of the first superheterodyne structure is becoming higher and higher, and therefore more expensive, which is an IF sampling structure of most of the major disadvantages of .
due to this reason, based on intermediate frequency sampling of the RF structure tend to be more suitable for those with a relatively low frequency, or IF applications,After all these bands to the cost of the impact is not big but due to this reason, based on intermediate frequency sampling of the RF structure tend to be more suitable for those with a relatively low frequency, or IF applications,After all these bands to the cost of the impact is not big but . Along with the development of science and technology, particularly CMOS technology is introduced, so that the performance of the integrated circuit device and the like are cheaper, in the near future, IF sampling structure will no longer be a choice of expensive Along with the development of science and technology, particularly CMOS technology is introduced, so that the performance of the integrated circuit device and the like are cheaper, in the near future, IF sampling structure will no longer be a choice of expensive .
in radio frequency communication in the application of the third configuration is a direct conversion structure in radio frequency communication in the application of the third configuration is a direct conversion structure . due to direct conversion structure directly to baseband signals and RF signals in the same process as the mixed together, which makes the structure of the signal link is most simple, it needs a minimum of components with the other two structures are different,It will not be required in the IF and the surface acoustic wave (SAW) filter due to direct conversion structure directly to baseband signals and RF signals in the same process as the mixed together, which makes the structure of the signal link is most simple, it needs a minimum of components with the other two structures are different,It will not be required in the IF and the surface acoustic wave (SAW) filter .
direct conversion structure of the main advantages: cheap, miniaturization, low power consumption, and not related to the conversion device IF direct conversion structure of the main advantages: cheap, miniaturization, low power consumption, and not related to the conversion device IF . these advantages such that this structure is well suited to low power, portable terminal applications these advantages such that this structure is well suited to low power, portable terminal applications .
Still, some high performance devices used for the direct conversion structure applied in high - end market is opening the door Still, some high performance devices used for the direct conversion structure applied in high - end market is opening the door . as a matter of fact, it is the use of these high - performance device, so that a direct conversion structure is more and more attention because of the as a matter of fact, it is the use of these high - performance device, so that a direct conversion structure is more and more attention because of the .
in a direct conversion architecture in which there is no intermediate frequency processing unit,in - band blocking signal power will be transmitted directly to the mixer and analog - to - digital converter if the signal on a link containing the analog to digital converter) and a low - noise mixer in a direct conversion architecture in which there is no intermediate frequency processing unit,in - band blocking signal power will be transmitted directly to the mixer and analog - to - digital converter if the signal on a link containing the analog to digital converter) and a low - noise mixer . will ensure that the weak signal is not noise and the blocking signal is overwhelmed by the will ensure that the weak signal is not noise and the blocking signal is overwhelmed by the .
In addition, since the mixer has a high output swing and low distortion, the blocking signal is neither too the entire drive system is not modulated onto carrier signals where our needs In addition, since the mixer has a high output swing and low distortion, the blocking signal is neither too the entire drive system is not modulated onto carrier signals where our needs . For baseband superheterodyne receiver, if the local phase - locked loop and the RF input is present between the leak passage, at least have a DC offset for the For baseband superheterodyne receiver, if the local phase - locked loop and the RF input is present between the leak passage, at least have a DC offset for the .
and the global system for mobile communications (GSM), and similar support hopping of some RF applications,frequency hopping will cause the local leakage of the phase - locked loop is changed, and eventually cause the entire system of the DC offset of the hopping and the global system for mobile communications (GSM), and similar support hopping of some RF applications,frequency hopping will cause the local leakage of the phase - locked loop is changed, and eventually cause the entire system of the DC offset of the hopping . If you want to correct it, must be in the system interjects a dc offset compensation loop If you want to correct it, must be in the system interjects a dc offset compensation loop .
Still, to those who do not need a frequency hopping application, a native of the leakage - locked loop is changed, and therefore the dynamic DC offset compensation is of little consequence. at the transmission end, due to the inability to effectively reduce the in - band noise and distortion, using a direct conversion structure of the radio frequency transmitter is necessary is judged primarily by the large dynamic range of the components constituting the at the transmission end, due to the inability to effectively reduce the in - band noise and distortion, using a direct conversion structure of the radio frequency transmitter is necessary is judged primarily by the large dynamic range of the components constituting the .
in a base station of the related application, due to the area and the channel density is to be considered,direct conversion structure is particularly bullish on the in a base station of the related application, due to the area and the channel density is to be considered,direct conversion structure is particularly bullish on the . because the distance from the base station perspective, in - band blocking signal is not present (i.e. the base station itself in the process in - band blocker signal), so even if direct conversion structure and the lack of out - of - band blocking signal the function of which is also acceptable to
, of course, the choice of the radio frequency circuit structure should be decided by the market application to guide the design of the , of course, the choice of the radio frequency circuit structure should be decided by the market application to guide the design of the . these factors include: from design to product time to market, cost, appearance, function, flexibility,whether it can support a variety of different application mode and the like these factors include: from design to product time to market, cost, appearance, function, flexibility,whether it can support a variety of different application mode and the like .
how one determines the application to select a suitable radio frequency structure is not introduced within the scope of the how one determines the application to select a suitable radio frequency structure is not introduced within the scope of the . clear now that some of RF device manufacturers have provided various services may be targeted to help us design a suitable radio - frequency system, throughout the design process, they may even be provided by several experienced and key to our FAQ clear now that some of RF device manufacturers have provided various services may be targeted to help us design a suitable radio - frequency system, throughout the design process, they may even be provided by several experienced and key to our FAQ .
power management in the whole process of research and development, or you don't understand many of the related art, the more you can optimize your design power management in the whole process of research and development, or you don't understand many of the related art, the more you can optimize your design . for example,Are you in the design by using a relatively expensive device may reduce the cost of the entire system, in other words, sometimes in some device Invest a few cents, it might be sufficient to extend the same battery using time for example,Are you in the design by using a relatively expensive device may reduce the cost of the entire system, in other words, sometimes in some device Invest a few cents, it might be sufficient to extend the same battery using time .
Another pitfall is that the power detector, it will generate the actual transmit power of the transmitter is compared with a theoretical value to determine whether or not the layout of the affordable range Another pitfall is that the power detector, it will generate the actual transmit power of the transmitter is compared with a theoretical value to determine whether or not the layout of the affordable range . due to transmission signal when the transmitter must operate at a certain power range, plus actual environment will cause the power consumption of the circuit structures of the jump,The power detector of role is very important when due to transmission signal when the transmitter must operate at a certain power range, plus actual environment will cause the power consumption of the circuit structures of the jump,The power detector of role is very important when .
terminal transmit power is lower than the theoretical range, the base station will not recognize this signal, on the contrary, if the terminal transmit power exceeds the theoretical range, this signal will be covered by the adjacent signal terminal transmit power is lower than the theoretical range, the base station will not recognize this signal, on the contrary, if the terminal transmit power exceeds the theoretical range, this signal will be covered by the adjacent signal . but, from the standpoint of power consumption, if the transmit power of the system in theory on the high end, will result in relatively more power consumption of the system, and eventually reduce the service life of the battery, unless a certain system through a combination of higher transmit power to rid the contention but, from the standpoint of power consumption, if the transmit power of the system in theory on the high end, will result in relatively more power consumption of the system, and eventually reduce the service life of the battery, unless a certain system through a combination of higher transmit power to rid the contention .
More generally speaking, the device's transmit power approaches the lower end of a range of theories,battery the higher the More generally speaking, the device's transmit power approaches the lower end of a range of theories,battery the higher the . if possible which causes the device to stay in the theory of transmit power for the low, there must be a very sensitive detector to ensure power transmission power does not drop out of the theory on the acceptable power range, and therefore, the low transmit power (i.e. low power) with the sensitivity of the detector power
trade - off exists between the logarithm of the power detector may be based on a very wide dynamic range provides high precision of power detection, the measurement objects may be either a few milliwatts of power in weak signal,may also be power in Watts of the strong signal trade - off exists between the logarithm of the power detector may be based on a very wide dynamic range provides high precision of power detection, the measurement objects may be either a few milliwatts of power in weak signal,may also be power in Watts of the strong signal . in similar to the wireless LAN standard (802.11) or WiMAX wireless broadband standard of some wireless communication standard, the signals are at the peak of the jump leads based on the ratio of the logarithmic power detector sensitivity drop
For example, when a terminal from a low rate of data exchange (such as uploading a plain - text information is shifted to a high rate of data exchange (such as downloading a new logo and graphics or sound files), the exchange rate of the dynamic modulation of growth and leads to a change in the signal ratio of the peak of the jump, at the same time,Based on the logarithmic power detector will more or less than normalthe detected transmit power;If the final result of the detection is too high, would cause the system to automatically reduce transmit power, when the actual power is below the theoretical power limit of the range, the entire communication will be aborted For example, when a terminal from a low rate of data exchange (such as uploading a plain - text information is shifted to a high rate of data exchange (such as downloading a new logo and graphics or sound files), the exchange rate of the dynamic modulation of growth and leads to a change in the signal ratio of the peak of the jump, at the same time,Based on the logarithmic power detector will more or less than normalthe detected transmit power;If the final result of the detection is too high, would cause the system to automatically reduce transmit power, when the actual power is below the theoretical power limit of the range, the entire communication will be aborted . above for this type of application, the root - mean - square (RMS) power detector, more appropriate, above for this type of application, the root - mean - square (RMS) power detector, more appropriate, .
rms power detector can not only operate over a very wide dynamic range, it is also possible to exchange rate jumps to accurately detect the rms power detector can not only operate over a very wide dynamic range, it is also possible to exchange rate jumps to accurately detect the . transmit power, however, have the same wide dynamic range of the rms power detector based on the ratio of the logarithmic power detector is slightly more expensive, and therefore,In price and performance on striking a compromise transmit power, however, have the same wide dynamic range of the rms power detector based on the ratio of the logarithmic power detector is slightly more expensive, and therefore,In price and performance on striking a compromise .
if your application does not require high accuracy, based on a logarithmic power detector or a narrower dynamic range of the rms power detector which are undoubtedly your money - saving option if your application does not require high accuracy, based on a logarithmic power detector or a narrower dynamic range of the rms power detector which are undoubtedly your money - saving option . device size for a portable terminal device, and the size of the size of the design is an important consideration as the factors device size for a portable terminal device, and the size of the size of the design is an important consideration as the factors .
because of the many RF applications in the field of portable products, chip vendors often require many different encapsulation modes because of the many RF applications in the field of portable products, chip vendors often require many different encapsulation modes . smaller packages often mean a more high - performance requirements, we must pay attention to when the package size is small to a certain extent, smaller packages often mean a more high - performance requirements, we must pay attention to when the package size is small to a certain extent,.
will die due to the package size is becoming smaller and smaller, when the chip operates in the transmit mode, the radiation will be increasingly difficult will die due to the package size is becoming smaller and smaller, when the chip operates in the transmit mode, the radiation will be increasingly difficult . To solve this problem, many of the often small package using a heatsink to reduce the thermal impedance of the chip it To solve this problem, many of the often small package using a heatsink to reduce the thermal impedance of the chip it .
at best, a pin and a thin layer of the plastic housing to protect the die at best, a pin and a thin layer of the plastic housing to protect the die . when you decided to design the respective functional modules must be seriously considered for the design of the final application in which the radiofrequency domain.
For example, you might need to offer your customers a series based on the local frequency of the radio communication system in consideration of a design of For example, you might need to offer your customers a series based on the local frequency of the radio communication system in consideration of a design of . a radiofrequency communication system complexity,the most advantageous way is to first build a simple application of but can do a number of adaptations (such as supporting multiple frequency) radiofrequency communication system a radiofrequency communication system complexity,the most advantageous way is to first build a simple application of but can do a number of adaptations (such as supporting multiple frequency) radiofrequency communication system .
if with this method, you only need a little time to establish an available RF communication systems, and more time to meet the special needs of those for the Design if with this method, you only need a little time to establish an available RF communication systems, and more time to meet the special needs of those for the Design ., for example, a range of DC to 10 GHz power detector may be applicable to any wireless standard , for example, a range of DC to 10 GHz power detector may be applicable to any wireless standard .
If you use more accurate, more stable (e.g., temperature) on the stability of high - quality devices, and related to the application does not require such high accuracy and stability,This will undoubtedly increase design costs of as possible using a single device may be able to fully offset the other part of the cost and the as possible using a single device may be able to fully offset the other part of the cost and the .
at the same time, it is also possible to design to shorten the product time to market at the same time, it is also possible to design to shorten the product time to market . If you want to consider in your designs were introduced to the RF technology, you don't hurry a decision to implement a radio frequency function of the structure in a final decision before If you want to consider in your designs were introduced to the RF technology, you don't hurry a decision to implement a radio frequency function of the structure in a final decision before .
structure, you have to think of the vendor of the application market, and those who are over time, some new radio - frequency functions - will be required to give your product portfolio structure, you have to think of the vendor of the application market, and those who are over time, some new radio - frequency functions - will be required to give your product portfolio .
Medical Application
RF wrinkle is a non - invasive treatment, is currently the safest, most effective method of beautifying wrinkle - removing wrinkle RF wrinkle is a non - invasive treatment, is currently the safest, most effective method of beautifying wrinkle - removing wrinkle . one of the radio frequency based on the principle that the radio waves penetrate the epidermal melanocytes of the barrier, the dermis collagen fiber was heated to 55.d egree. - 65.degree. C., contraction of collagen fibers, so that the slack of skin wrinkles is tensioned, so as to achieve the cosmetic wrinkle - removing wrinkle -
of the destination radio frequency characteristics 1 characteristics: high efficiency, the experiments demonstrate that the RF de - wrinkling and effectively stimulate 8 recombinant collagen, tighten skin, reduce wrinkles, after the treatment are more satisfied with the characteristics of of the destination radio frequency characteristics 1 characteristics: high efficiency, the experiments demonstrate that the RF de - wrinkling and effectively stimulate 8 recombinant collagen, tighten skin, reduce wrinkles, after the treatment are more satisfied with the characteristics of . 2: security, the radio frequency system can protect the skin wrinkle,achieve a secure and efficient has been satisfactory, than other non - invasive treatment for more security 2: security, the radio frequency system can protect the skin wrinkle,achieve a secure and efficient has been satisfactory, than other non - invasive treatment for more security .
In addition, after the treatment period of convalescence, the patient can immediately resume their daily schedule, eliminating the other post - treatment necessary precautions In addition, after the treatment period of convalescence, the patient can immediately resume their daily schedule, eliminating the other post - treatment necessary precautions . 3 features: persistent, after treatment, new collagen continued continuously produced, the skin will have to improve every day 3 features: persistent, after treatment, new collagen continued continuously produced, the skin will have to improve every day .
and in the 4 position for 6 months, more significantly, a satisfactory effect of and in the 4 position for 6 months, more significantly, a satisfactory effect of .
Recognition System
Identification technology of radio frequency identification technology which employs a different frequency than the frequency of the system can be divided into low frequency and high frequency systems.According to the electronic tag whether the mounted battery as its power supply, which in turn can be divided into active systems and passive systems.From the electronic tag to display the information of the injection mode of the integrated circuit can be subdivided into curable type, site type wired and wireless rewriting rewriting the field type.in accordance with the read electronic tag data of the means, which can be divided into broadcast transmission type, reflection type and frequency doubling modulation type three 1. The outputs of the system typically operates at a frequency of less than 30 MHz, a typical operating frequency: 125 kHz, 225KHz, 13.56 MHz or the like, and these frequency points of the application of radio frequency identification (RFID) system generally have the corresponding international standards support
is characterized by its relatively low cost of the electronic tag, the tag that is stored in the data amount is relatively small, relatively short reading distance (passive case, the typical distance of 10cm) electronic label diversified in form (the card - like, ring - shaped, button - shaped,pen - like), the directivity of the antenna of the reading is not strong, etc. The high frequency system usually refers to a frequency in excess of 900 MHz, with typical operating frequencies are 915 MHz, 2450 MHz, 5800 and the like of the radio - frequency system in these frequency bands also has the numerous international standards in support of and the like of the radio - frequency system in these frequency bands also has the numerous international standards in support of .
high frequency system is the basic characteristics of the electronic tag and reader are rather high, and the tag that is stored in the data amount is large, the reading distance is relatively long (up to several meters to several meters), the object's high - speed movement performance is good, the outline of the shape of a card,The antenna and electronic tag reading antenna has strong directivity high frequency system is the basic characteristics of the electronic tag and reader are rather high, and the tag that is stored in the data amount is large, the reading distance is relatively long (up to several meters to several meters), the object's high - speed movement performance is good, the outline of the shape of a card,The antenna and electronic tag reading antenna has strong directivity . 3. active electronic tag are built in each of the battery, generally has a far reading distance, is due to the limited life of the battery (3 ~ 10 years);passive electronic tag without a battery, which is received by the reader (reading device) of a microwave signal, a portion of the microwave energy is converted to direct current power for their own work, and generally can have a maintenance - free
compared to the active system, the passive system at the reading distance and the object's movement speed and the minor restriction compared to the active system, the passive system at the reading distance and the object's movement speed and the minor restriction . system composed of the most basic RFID system consists of three parts: 1. the tags, i.e., RF card): consists of a coupling element and a chip and the tag contains built - in antenna for radio - frequency antenna and the communication is performed between the
2. Reader: (read - write card) can also be written in the tag information of the equipment 3 . antenna:In the tag and the reader RF signal transmission between the
some systems by means of a reader of the RS232 or RS485 interface with an external computer (master) is connected to the system, the data exchange system working principle some systems by means of a reader of the RS232 or RS485 interface with an external computer (master) is connected to the system, the data exchange system working principle . work flow is: the reader through the transmit antenna to transmit a certain frequency of the RF signal, the RF antenna transmitting when entering the working area when the induction current is generated, the obtained energy is activated;RF card itself, or the like for the information transmitted by the card in the built - in antenna;system transmission antenna is received from the radio - frequency carrier signal sent by antenna regulator is transmitted to the reader, the reader signal and demodulates and decodes a received signal is then sent to the backend host system to perform the correlation process; andmain logic operation system according to the judgment of the legitimacy of the card, for different corresponding to the setting of the processing and control, an instruction signal to the control action of the actuator in a coupled manner ( work flow is: the reader through the transmit antenna to transmit a certain frequency of the RF signal, the RF antenna transmitting when entering the working area when the induction current is generated, the obtained energy is activated;RF card itself, or the like for the information transmitted by the card in the built - in antenna;system transmission antenna is received from the radio - frequency carrier signal sent by antenna regulator is transmitted to the reader, the reader signal and demodulates and decodes a received signal is then sent to the backend host system to perform the correlation process; andmain logic operation system according to the judgment of the legitimacy of the card, for different corresponding to the setting of the processing and control, an instruction signal to the control action of the actuator in a coupled manner (.
- electromagnetic inductance), the communication process (FDX and HDX, SEQ), from the card to the reader of the data transmission method (the load modulation, a backscattering of the high - order harmonic) and frequency range, different non - contact transmission methods differ, but all of the reader functions in principle, as well as design configuration are very similar,All reader can simplify the interface control unit for high frequency and high frequency module of the two basic - electromagnetic inductance), the communication process (FDX and HDX, SEQ), from the card to the reader of the data transmission method (the load modulation, a backscattering of the high - order harmonic) and frequency range, different non - contact transmission methods differ, but all of the reader functions in principle, as well as design configuration are very similar,All reader can simplify the interface control unit for high frequency and high frequency module of the two basic . interface comprising a transmitter and a receiver, whose functions include: generating a high frequency power and provides energy to activate the RF card;a transmit signal for modulation, for transmitting data to RF card;receiving and demodulating the signal from the radio - frequency signal of high frequency radio frequency identification system interface comprising a transmitter and a receiver, whose functions include: generating a high frequency power and provides energy to activate the RF card;a transmit signal for modulation, for transmitting data to RF card;receiving and demodulating the signal from the radio - frequency signal of high frequency radio frequency identification system .
different interface design has some differences, the inductively coupled high - frequency interface schematic is shown in Figure 1 different interface design has some differences, the inductively coupled high - frequency interface schematic is shown in Figure 1 . reader function of the control unit includes: performing communication with the application software, and executing the application software from the command;Radio frequency (RF) communication with the control of the process (master - slave principle);the signal codec reader function of the control unit includes: performing communication with the application software, and executing the application software from the command;Radio frequency (RF) communication with the control of the process (master - slave principle);the signal codec .
on some particular systems as well as perform algorithms, and RF card reader and used to encrypt and decrypt data transmitted between the reader and the RF card and performs authentication of the additional functions such as radio frequency identification system on some particular systems as well as perform algorithms, and RF card reader and used to encrypt and decrypt data transmitted between the reader and the RF card and performs authentication of the additional functions such as radio frequency identification system . of the read - write distance is a very critical parameter of the read - write distance is a very critical parameter .
long distance radio frequency identification (RFID) systems are also very expensive and are therefore looking to enhance their reading distance is very important method of long distance radio frequency identification (RFID) systems are also very expensive and are therefore looking to enhance their reading distance is very important method of . influence factors include the distance of the RF antenna operating frequency, the output power of the RF reader, the reader receiver sensitivity, power consumption of the RF card, the antenna and the Q value of the resonance circuit, the antenna direction,and the degree of coupling of the RF card reader, the card itself and the obtained energy of the energy and can be used such as influence factors include the distance of the RF antenna operating frequency, the output power of the RF reader, the reader receiver sensitivity, power consumption of the RF card, the antenna and the Q value of the resonance circuit, the antenna direction,and the degree of coupling of the RF card reader, the card itself and the obtained energy of the energy and can be used such as .
most system of reading and writing distance distance is different, writes the read distance is a distance of about 40% ~ 80% most system of reading and writing distance distance is different, writes the read distance is a distance of about 40% ~ 80% .
Industrial Application
Economizer hopper of the applicable plant operating conditions, the ash conveying system, the desulfurization system, coal conveying system on groove of blast furnace steel ore, iron powder, coke, pellets, sinter, slag, etc., pulverized coal injection system of pulverized coal, the coke dry quenching cement cooler grate ash hopper, raw meal, clinker, limestone powder, cement, silicate such as chemical PVC / PP / BPA / PTA etc, coal chemical, coal to olefin project and environment - friendly dust - removing process and the like, food, animal feed, building materials and foundry, mining, metallurgy, machinery, pharmaceutical, brewery industries were industrial application significance of using radio frequency admittance material level switch UWT effectively avoid risking overflow of the bin, the bin empty take - off, etc., to avoid polluting the environment,Green environmental protection, waste, save energy, prevent accidents and avoid downtime, improve the factory benefit Introduction UWT radio frequency admittance material level switch, is by the capacitive level switch of the technique which was developed, which is a capacitive version of some old, has a widely application in the self - calibration, actively shielded, accurate and reliable Introduction UWT radio frequency admittance material level switch, is by the capacitive level switch of the technique which was developed, which is a capacitive version of some old, has a widely application in the self - calibration, actively shielded, accurate and reliable .
UHF radio frequency, i.e., admittance is the reciprocal of impedance, including resistive, capacitive and inductive three parts,English is a Radio Frequency Level Switch. The abbreviation RF. The working principle of radio frequency admittance material level switch through a probe electrode and the grounded main protection between emits a magnetic field, the inductive probe main electrode around the admittance value of the variation, when the material covers one half of the blade, the admittance value is changed, the electronic module is sensed by the switch point signal, and output a corresponding alarm switching quantity classification according to different application condition. It can be classified into standard type, heavy duty and high - temperature type three;Depending on the installation mode and transmission mode, the rod may be divided into extended type, cable type and split type extension such as
radio frequency admittance material level switch has a variety of series and models to meet different conditions of application: 1) the general conditions of general application, standard and RF3100 series, the resistance to pressure of 25 bar, which is resistant to 240.d egree. C., such as the ash bucket, ash, fly ash, coal powder, flour, fodder, plastic particles, sand particles, the lithium powder, mineral powder and the like;2) high mechanical loading conditions for the application, may select a heavy - duty type RF3200 series, the resistance to pressure of 25 bar, which is resistant to 240. degree. C., resistance to mechanical load 40kN 525Nm & or up to 90 Nm, such as coal, ore, iron powder, copper powder and the high - density block and powder and the like;3) the high - temperature applications, it is possible to select either the high - temperature type RF3300 series, resistant to high temperatures up to + 500 DEG C, such as cement plants, grate ash hopper of economizer hop plant, steel plant dust, coal, high temperature pulverized coal, coke and coke powder;4) applies to the dangerous occasion, provide various forms of explosion - proof: intrinsically safe type ia explosion - type d - de;5) is mounted a threaded interface can be 3 / 4 "NPT (/ G), the selection of RF3100 series;Application of UWT radio frequency admittance material level switches are used in a variety of applications, suitable for almost all of the solid material level measuring as coal bunker material level switch, a switch, a discharge hopper, hopper, economizer hopper, grate ash hopper, a blast - furnace on groove of blast furnace, coke, coking coal and coke powder, synthetic fiber, synthetic resin, synthetic plastics, food, feed, cement, pulpwood, casting, etc., may be applied to the selection of
UWT general radio frequency admittance material level switch, and affected by the restriction of sense principle, type selection and some problems needing attention are as follows: 1) cannot be applied in the case of particularly low dielectric constant materials, and general advice on the DK is greater than or equals to 1. 5,If less than 1. 5, subject to a separate Advisory; 2) cannot be applied to the material of severe erosion of working conditions, suggest to install with the erosion of the materials is avoided; 3) cannot measure filiform object; 4) according to different material densities, the selection of different transmission forms and protection; 5) provide the right and to the operating condition information, including a certificate for the temperature, pressure, or the like structure the size of the silo content, in order to select the suitable model of .
. the technical characteristics of UWT radio frequency admittance material level switch of the following characteristics: 1); completely maintenance - free; 2) the patented design of the active shield technique, effectively prevent dust, moisture etc. interfere with the viscous material;3) protection class IP67, the complete isolation of the entering of the dust, suitable for outdoor installation; 4) Intelligent self - calibration, self - diagnosis technology; 5) are flexible and selectable calibration in such a way that: initial power - on of the automatic calibration, automatic calibration, a calibration button, manual calibration standard 6) universal power supply voltage, an AC / DC power supply auto - switching; 21 230VAC / DC DPDT relay outputs; 7) LCD display, which can detect when the actual capacitance value, accurate setting of the switch point; and a state indication signal output from the diagnostic information; 8) low temperature up to 40 DEG C, the high temperature resistant up to 500 DEG C;high pressure resistant up to 24 bar; high temperature resistance of the explosionproof 445.d egree. C.; 9) the operating frequency: 100 kHz; signal output delay: 0. 5 - 60 seconds; the measuring range / sensitivity: 3 100 pF / 0.1 pF or 3 400 pF / 2pF; high and low level alarm failure adjustable / FSL and FSH; 10) to provide various international certification: FDA & 1935 / 2004 / EC of the food grade certification; EHEDG certified organization European Hygienic Equipment Design; ATEX / IEC Ex - / FM / FMc Explosion - Proof and Dust and gas explosion - proof certification;
Card Sorting
Production of RFID products and many companies have to adopt our own standards, there is no unified standard for the Production of RFID products and many companies have to adopt our own standards, there is no unified standard for the . .
ISO18OOO. The most prominent is the ISO 14443 and ISO 15693, Both of these standards by the physical characteristics of the radio frequency power and signal interface, the initialization and anti - collision, as well as the transmission protocol is composed of four sections: according to different available are limited, the following classification: 1. The power supply card is divided into active and passive card active
means the battery card there is provided a power transmission distance is far, but have a limited lifespan, large volume, high cost, and is not suitable for bad work environment;passive card without battery, which uses beam - powered technology of converting the received radio frequency energy into direct - current power supply circuit for the card. The transmission distance is relatively short active card, but a long life and the working environment does not require high 2. The carrier frequency is divided into low, intermediate and high frequency RF card, RF card, RF card mainly
low frequency 125 kHz and 134 kHz, IF and RF frequency of 13.56 MHz, the RF card and the main frequency of 433 MHz, 915 MHz, 2.45 GHz, 5.8 GHz, etc the low - frequency system is mainly used for short range, low - cost applications,If a plurality of access control, campus card, animal control, cargo tracking and the low - frequency system is mainly used for short range, low - cost applications,If a plurality of access control, campus card, animal control, cargo tracking and .
IF system for access control and the need to transfer large amounts of data of the application system;radio - frequency system, which needs to be a longer working distance and high write speed, the direction of the antenna beam is narrow and the price is high, and a monitored train, highway tolls in IF system for access control and the need to transfer large amounts of data of the application system;radio - frequency system, which needs to be a longer working distance and high write speed, the direction of the antenna beam is narrow and the price is high, and a monitored train, highway tolls in . 3. according to different modulation modes may be divided into active and passive
active RF card will use our own radio frequency energy is transmitted to the reader / writer;Passive radio frequency modulation using a light scattering method, transmit data, it must use the reader / writer by modulating the carrier signal itself, such techniques are suitable for use in access control or traffic application, because the reader / writer can be ensured only within a certain range of the activation of the RF card active RF card will use our own radio frequency energy is transmitted to the reader / writer;Passive radio frequency modulation using a light scattering method, transmit data, it must use the reader / writer by modulating the carrier signal itself, such techniques are suitable for use in access control or traffic application, because the reader / writer can be ensured only within a certain range of the activation of the RF card . in the presence of obstacle, for example, with modulation / light scattering method, the reader / writer of the energy necessary to go through the obstacle in the presence of obstacle, for example, with modulation / light scattering method, the reader / writer of the energy necessary to go through the obstacle .
twice while the active mode of the RF transmit signal passes through only one obstacle, the driving manner of the RF card is mainly used when an obstacle exists in the application,more distant (up to 30 metres) twice while the active mode of the RF transmit signal passes through only one obstacle, the driving manner of the RF card is mainly used when an obstacle exists in the application,more distant (up to 30 metres) . 4. The distance can be divided into close - coupled cards (distance of less than 1 cm), in close - coupled card function (the distance is less than 15 cm), the loosely coupled card function (a distance of about 1 m) and distance (operating distance of the card from 1 meter to 10 meters, even more far)
5. The wafer is divided into only the reading card, writing card and CPU card
