CN116582118B - RFID antenna virtual switch circuit and multi-antenna multiplexing device - Google Patents
RFID antenna virtual switch circuit and multi-antenna multiplexing device Download PDFInfo
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- CN116582118B CN116582118B CN202310847212.2A CN202310847212A CN116582118B CN 116582118 B CN116582118 B CN 116582118B CN 202310847212 A CN202310847212 A CN 202310847212A CN 116582118 B CN116582118 B CN 116582118B
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/51—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used
- H03K17/56—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices
- H03K17/60—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices the devices being bipolar transistors
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
- G06K7/00—Methods or arrangements for sensing record carriers, e.g. for reading patterns
- G06K7/10—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
- G06K7/10009—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves
- G06K7/10019—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves resolving collision on the communication channels between simultaneously or concurrently interrogated record carriers.
- G06K7/10079—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves resolving collision on the communication channels between simultaneously or concurrently interrogated record carriers. the collision being resolved in the spatial domain, e.g. temporary shields for blindfolding the interrogator in specific directions
- G06K7/10089—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves resolving collision on the communication channels between simultaneously or concurrently interrogated record carriers. the collision being resolved in the spatial domain, e.g. temporary shields for blindfolding the interrogator in specific directions the interrogation device using at least one directional antenna or directional interrogation field to resolve the collision
- G06K7/10099—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves resolving collision on the communication channels between simultaneously or concurrently interrogated record carriers. the collision being resolved in the spatial domain, e.g. temporary shields for blindfolding the interrogator in specific directions the interrogation device using at least one directional antenna or directional interrogation field to resolve the collision the directional field being used for pinpointing the location of the record carrier, e.g. for finding or locating an RFID tag amongst a plurality of RFID tags, each RFID tag being associated with an object, e.g. for physically locating the RFID tagged object in a warehouse
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
- G06K7/00—Methods or arrangements for sensing record carriers, e.g. for reading patterns
- G06K7/10—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
- G06K7/10009—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves
- G06K7/10316—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves using at least one antenna particularly designed for interrogating the wireless record carriers
- G06K7/10346—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves using at least one antenna particularly designed for interrogating the wireless record carriers the antenna being of the far field type, e.g. HF types or dipoles
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
- G06K7/00—Methods or arrangements for sensing record carriers, e.g. for reading patterns
- G06K7/10—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
- G06K7/10009—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves
- G06K7/10316—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves using at least one antenna particularly designed for interrogating the wireless record carriers
- G06K7/10356—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves using at least one antenna particularly designed for interrogating the wireless record carriers using a plurality of antennas, e.g. configurations including means to resolve interference between the plurality of antennas
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q1/00—Details of, or arrangements associated with, antennas
- H01Q1/12—Supports; Mounting means
- H01Q1/22—Supports; Mounting means by structural association with other equipment or articles
- H01Q1/2208—Supports; Mounting means by structural association with other equipment or articles associated with components used in interrogation type services, i.e. in systems for information exchange between an interrogator/reader and a tag/transponder, e.g. in Radio Frequency Identification [RFID] systems
- H01Q1/2216—Supports; Mounting means by structural association with other equipment or articles associated with components used in interrogation type services, i.e. in systems for information exchange between an interrogator/reader and a tag/transponder, e.g. in Radio Frequency Identification [RFID] systems used in interrogator/reader equipment
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q1/00—Details of, or arrangements associated with, antennas
- H01Q1/50—Structural association of antennas with earthing switches, lead-in devices or lightning protectors
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q21/00—Antenna arrays or systems
- H01Q21/0006—Particular feeding systems
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/51—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used
- H03K17/56—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices
- H03K17/60—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices the devices being bipolar transistors
- H03K17/62—Switching arrangements with several input- output-terminals, e.g. multiplexers, distributors
- H03K17/6221—Switching arrangements with several input- output-terminals, e.g. multiplexers, distributors combined with selecting means
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Toxicology (AREA)
- General Health & Medical Sciences (AREA)
- Electromagnetism (AREA)
- Computer Networks & Wireless Communication (AREA)
- Artificial Intelligence (AREA)
- Computer Vision & Pattern Recognition (AREA)
- General Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Variable-Direction Aerials And Aerial Arrays (AREA)
- Near-Field Transmission Systems (AREA)
Abstract
The application discloses an RFID antenna virtual switch circuit and a multi-antenna multiplexing device, wherein the virtual switch circuit comprises a triode, an inductor and a diode; the triode is used for being in a conducting state when the virtual switch circuit is closed so that the high-frequency radio-frequency signals output by the RFID reader are transmitted to the antenna or the high-frequency signals received by the antenna are transmitted to the RFID reader, and being in a cutting-off state when the virtual switch circuit is opened so that the high-frequency radio-frequency signals output by the RFID reader cannot be transmitted to the antenna or the high-frequency signals received by the antenna cannot be transmitted to the RFID reader. The application realizes the on-off control of the RFID reader and the antenna by using the control signals overlapped in the high-frequency radio frequency signals, and realizes the flexible multiplexing of multiple antennas based on the multi-antenna multiplexing device of the virtual switch circuit, so that the real-time positioning system can fully utilize the receiving information of each antenna to accurately position the article marked by the RFID tag.
Description
Technical Field
The application belongs to the technical field of radio frequency identification, and particularly relates to an RFID antenna virtual switch circuit and a multi-antenna multiplexing device.
Background
Real-time location system (Real-Time Location System, RTLS) is an intelligent system for determining the location of an item in Real time, which is typically implemented by an ultra-high frequency RFID reader with multiple antennas, such as a radio frequency identification based intelligent shelf as shown in fig. 1, with various signal characteristics that can be used to infer the location of the RFID tag, such as signal strength, phase differences, etc., and the extracted data can be migrated to the cloud or processed locally by various location algorithms to determine the exact location information of the tag.
Although only 9 shelf compartments are shown in fig. 1, in practice larger topologies are possible. In the current market, many ultrahigh frequency RFID readers have the capability of driving 50-70 external antennas, and the driving capability is mostly realized through a radio frequency multiplexer. While the high fanning out of a single ultra-high frequency RFID reader core reduces the cost of system expansion, it also makes the system more complex and more difficult to implement and maintain. It was attempted to connect several tens of rf coaxial cables simultaneously to a single center, and this "pasta" cable arrangement would present a number of problems if the system were to be troubleshooted or maintenance needed.
A standard uhf rfid system supporting multiple antenna driving is shown in fig. 2: an ultra-high frequency RFID reader core operates as a single transceiver, interacting with a plurality of external ultra-high frequency RFID antennas through a low-loss radio frequency switch or polling device. Such an architecture is typically used to track RFID-tagged items across an area. When the intelligent shelf of fig. 1 is implemented by the architecture of fig. 2, the reader core simply processes each antenna in sequence, and when an object passes through a certain area, the motion track of the object can be obtained through the nearby antenna, but the information of other antennas is ignored in positioning, and the information is very useful for positioning the object in practice.
Disclosure of Invention
The application provides an RFID antenna virtual switch circuit and a multi-antenna multiplexing device, which are used for solving the technical problems that the existing RFID multi-antenna multiplexing system or polling device is complex in structure, difficult to maintain and incapable of fully utilizing multiple antennas to collect information during positioning. The technical scheme provided by the application is as follows:
an RFID antenna virtual switch circuit is serially connected between an RFID reader and an antenna and comprises a triode T SWITCH Inductance L ISOLATE And diode D SWITCH The method comprises the steps of carrying out a first treatment on the surface of the The triode T SWITCH The emitter and the collector of the antenna are correspondingly connected with the RFID reader and the antenna respectively; the inductance L ISOLATE One end of the (E) is connected with the RFID reader, and the other end is connected with the RFID reader through a diode D SWITCH And triode T SWITCH Is connected with the base electrode of the transistor; an impedance matching circuit is connected between the virtual switch circuit and the RFID reader as well as between the virtual switch circuit and the antenna;
the triode T SWITCH The virtual switch circuit is in a conducting state when being closed so that the high-frequency radio frequency signals output by the RFID reader are transmitted to the antenna or the high-frequency signals received by the antenna are transmitted to the RFID reader, and is in a cutting-off state when being opened so that the high-frequency radio frequency signals output by the RFID reader cannot be transmitted to the antenna or the high-frequency signals received by the antenna cannot be transmitted to the RFID reader;
the inductance L ISOLATE For switching on diode D when the RFID reader outputs a low frequency or DC control signal SWITCH So that triode T SWITCH Cut-off, cut-off diode D when the RFID reader does not output a control signal SWITCH So that triode T SWITCH Conducting;
the diode D SWITCH For passing through inductance L ISOLATE Is rectified;
the RFID reader is used for outputting a control signal or a superposition signal of a radio frequency signal and the control signal and receiving a high-frequency signal transmitted by the antenna;
the antenna is a transmitting antenna or/and a receiving antenna.
Further, the diode D SWITCH And triode T SWITCH A delay circuit is arranged between the transistors for delaying the triode T SWITCH Switching state between on and off and for smoothing across diode D SWITCH A rectified signal; the low-pass filter circuit is a resistor R connected in parallel SWITCH And a capacitorC SWITCH 。
Further, the triode T SWITCH And inductance L ISOLATE The resistor R is also connected in series LIMIT 。
Further, the impedance matching circuit is a capacitance-based matching bridge: between the virtual switch circuit and the RFID reader, a triode T SWITCH Through capacitor C MI1 Connected with RFID reader, capacitor C MI1 In parallel with capacitors C connected in series MI0 And capacitor C MI2 The method comprises the steps of carrying out a first treatment on the surface of the Between the virtual switch circuit and the antenna, a triode T SWITCH Through capacitance C MO1 Connected with the antenna, the capacitor C MO1 In parallel with capacitors C connected in series MO0 And capacitor C MO2 。
An RFID multi-antenna multiplexing device comprises an RFID reader, a control module, a plurality of antennas and the virtual switch circuits with the same number as the antennas, wherein each antenna is connected with the RFID reader through the virtual switch circuits respectively, and the inductance L in each virtual switch circuit is disconnected ISOLATE Connection to RFID reader, inductance L ISOLATE Is connected with the control module;
the control module is used for sending a control signal to the appointed virtual switch circuit according to the received control instruction, and the control signal passes through an inductor L in the virtual switch circuit ISOLATE So that the diode D in the virtual switch circuit SWITCH Conducting; the RFID reader selects any antenna in a plurality of antennas through the control module to be used for transmitting radio frequency signals or receiving signals transmitted back by the antenna.
The application has the beneficial effects that: the virtual switch circuit provided by the application realizes the on-off control of the RFID reader and the antenna by utilizing the low-frequency or direct-current control signals superposed in the high-frequency radio frequency signals, has a simple circuit structure and is easy to integrate and multiplex; based on the virtual switch circuit, the application also provides an RFID multi-antenna multiplexing device, and flexible multiplexing of multiple antennas is realized through a control module, so that a real-time positioning system can fully utilize the receiving information of each antenna to accurately position the article marked by the RFID tag.
Drawings
The accompanying drawings are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate the application and together with the embodiments of the application, serve to explain the application. In the drawings:
FIG. 1 is a schematic diagram of an intelligent shelf based on radio frequency identification;
FIG. 2 is a schematic diagram of the architecture of a standard UHF RFID system supporting multiple antenna driving;
FIG. 3 is a schematic diagram of the internal components of an ultra-high frequency RFID reader;
FIG. 4 is a schematic diagram of an extension assembly of the UHF RFID reader shown in FIG. 3;
FIG. 5 is a schematic diagram of a bus switch architecture;
FIG. 6 is an expanded schematic diagram of the bus switch architecture of FIG. 5;
FIG. 7 is a schematic diagram of a virtual switch circuit according to an embodiment of the present application;
fig. 8 is a schematic diagram of a multi-antenna multiplexing device according to an embodiment of the application.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present application more apparent, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments of the present application.
Fig. 3 is a schematic diagram of the internal components of the uhf RFID reader, and the carrier signal generating module is one of the more important components. The carrier signal is modulated by forward link baseband signal information. Modulation schemes currently in widespread use include PIE (pulse interval coding) and ASK (amplitude shift keying), and the backscatter signal of an RFID tag employs a modified mueller coding method so that the backscatter signal can be detected by other antennas in a multi-antenna system. The critical components also include a power amplifier to amplify the modulated signal to an appropriate power level to drive the antenna. If a high power level is required, an external dedicated power amplifier is typically employed. Bandpass filtering and impedance matching of the drive signal is also necessary to ensure that the reader does not emit extraneous frequency signals outside the target frequency band. For antennas that are both transmitters and receivers, the critical components of the ultra-high frequency RFID reader also include a circulator to process both the forward link with high power levels and the weak received signal from the tag back-scattering. The acquired signal is demodulated after bandpass filtering to remove out-of-band content to extract data information from the backscattered signal generated by the tag.
This overall architecture is not only applicable to a single transceiver core, but it can also receive signals from external antennas. Fig. 4 shows an extension of this architecture to meet the number of more extensive ultra-high frequency RFID antennas. The additional channels in the figure also include mechanisms for signal cancellation to reject the primary carrier and extract the weaker back-scattered signal. Although digital data extraction is not required in these additional channels, an IQ demodulation method is also reserved for extracting useful RSSI and phase information. This signal integration provides a useful basis for tag locating from which the locating algorithm can use rich information to determine the exact location of the tag to be located.
Conventionally, the ultrahigh frequency RFID reader and the antenna are connected through coaxial cables respectively, and the characteristic impedance of the coaxial cables is matched with the output impedance of the reader and the input impedance of the ultrahigh frequency RFID antenna. Or the connection cable between the reader and the RFID antennas is replaced by a unified bus, and a local isolation mechanism is applied to the bus, so that the system can select different antennas. Fig. 5 shows an example of a bus with 8 antennas, of course more or fewer antennas may be provided depending on the application. In fig. 5, the separate control lines are bundled with the radio frequency cable, and the control mechanism is similar to that of the I2C address-based control and sensing bus, each antenna is provided with a unique physical address, and whether each antenna is added into the signal receiving and transmitting bus or not is controlled by the physical address, and in practical application, the connection or disconnection of the low-loss radio frequency switch is used for controlling the connection or disconnection of the antenna, such as a DIP switch.
Fig. 6 extends the bus switch architecture of fig. 5, which not only facilitates switching and selection of transmit antennas, but also facilitates selection of any receive antennas. This topology is beneficial in an RFID tag location scenario. For multi-antenna systems with predefined geometries, the acquired signals provide a large number of propagation path distances from which specific tags associated with antenna locations can be located. This method requires a continuous loop through all transmit antennas and, for each transmit instance, a loop through a receive antenna combination, resulting in a large amount of propagation data from which the location of the tag can be determined.
Unlike the bus architecture based on independent control cable shown in fig. 5 and 6, the present application proposes a virtual switch circuit of RFID antenna, as shown in fig. 7, which is serially connected between RFID reader and antenna and comprises triode T SWITCH Inductance L ISOLATE And diode D SWITCH . Triode T SWITCH The emitter and the collector of the antenna are respectively and correspondingly connected with the RFID reader and the antenna, and the inductance L ISOLATE Is connected to the RFID reader at one end and a diode D at the other end SWITCH And triode T SWITCH Is connected to the base of the transistor.
During normal operation, the virtual switch circuit is in a closed mode, allowing high frequency radio frequency signals to pass from the reader to the transmit antenna. When the superimposed signal of the high-frequency radio frequency signal and the low-frequency or direct-current control signal enters the virtual switch circuit, the inductor L ISOLATE The branch circuit blocks the transmission of high-frequency signals, but allows the low-frequency or direct-current control signals to pass through, and the control signals pass through a high-speed rectifying diode D SWITCH Reach triode T SWITCH So that triode T SWITCH The potential of the base electrode rises to further enable the triode T SWITCH The switch is turned from on state to off state, and the high-frequency radio frequency signal can not be transmitted to the transmitting antenna, i.e. the virtual switch circuit is in an off mode. Similarly, for a receiving antenna, if the virtual switch circuitIn closed mode, the high-frequency signal received by the receiving antenna is allowed to pass to the reader, and when a low-frequency or direct-current control signal is present, the triode T SWITCH By cutting off, the high frequency signal received by the receiving antenna cannot be transmitted to the reader. In practical applications, the same antenna is often both a transmitting antenna and a receiving antenna.
An impedance matching circuit is connected between the virtual switch circuit and the RFID reader and between the virtual switch circuit and the antenna, and in the embodiment shown in fig. 7, the impedance matching circuit is a capacitance-based matching bridge: between the virtual switch circuit and the RFID reader, transistor T SWITCH Emitter pass capacitor C MI1 Connected with RFID reader, capacitor C MI1 In parallel with capacitors C connected in series MI0 And capacitor C MI2 The method comprises the steps of carrying out a first treatment on the surface of the Between the virtual switch circuit and the antenna, transistor T SWITCH Through the collector of capacitor C MO1 Connected with the antenna, the capacitor C MO1 In parallel with capacitors C connected in series MO0 And capacitor C MO2 。
In some embodiments, to provide a slower response to the switching action (delay transistor T SWITCH State switching between on and off), at diode D SWITCH And triode T SWITCH A delay circuit is also arranged between the two resistors, as shown in figure 7, which are parallel resistors R SWITCH And capacitor C SWITCH . The delay circuit also provides a low-pass frequency function with a certain time constant to smooth the signal passing through the diode D SWITCH Is dependent on the resistance R SWITCH And capacitor C SWITCH Can be selectively set according to specific application scenes.
In some embodiments, transistor T SWITCH And inductance L ISOLATE The resistor R is also connected in series LIMIT 。
As shown in fig. 8, based on the virtual switch circuit, the application further provides an RFID multi-antenna multiplexing device, which comprises an RFID reader, a control module, a plurality of antennas and the virtual switch circuit with the same number as the antennas, wherein each antenna passes through a virtual circuit respectivelyThe switch circuits are connected with the RFID reader, and the inductors L in the virtual switch circuits are disconnected ISOLATE Connection to RFID reader, inductance L ISOLATE Is connected with the control module. The control module is used for sending a control signal to the appointed virtual switch circuit according to the received control instruction, wherein the control signal is a direct current or low frequency signal and can pass through the inductor L ISOLATE So that the diode D in the virtual switch circuit SWITCH Conducting to make triode T SWITCH And the high-frequency radio frequency signals output by the RFID reader cannot be transmitted to the antenna at the moment, and the high-frequency signals received by the antenna cannot be transmitted to the RFID reader. When no control signal is sent to the virtual switch circuit, transistor T SWITCH The antenna connected with the virtual switch circuit is conducted, so that normal radio frequency signal receiving and transmitting can be performed. Thus, the RFID reader can select any antenna in a plurality of antennas through the control module for transmitting radio frequency signals or receiving signals transmitted back by the antenna. The control command of the control module is from a selection button arranged on the control module or from related control commands given by other electrical elements.
As previously mentioned, the antenna multiplexing can also be achieved by virtual control channels by superimposing signals of different frequencies on the outgoing transmit feeder cable (radio frequency signals of high frequency and control signals of low frequency or direct current). It is therefore necessary to divide the frequency bands of the control signal and the radio frequency signal to be transmitted/received. In some embodiments, the frequency range of the radio frequency transmission and reception is 865-960 MHz, and the control signal is a DC signal or an ISM band at 433 MHz. In 433 MHz control systems, switching logic selection is achieved by notch filtering of the superimposed 433 MHz control signal.
Finally, it should be noted that: the technical features of the above embodiments or in the different embodiments may also be combined within the idea of the application, the steps may be implemented in any order, and there are many other variations of the different aspects of the application as described above, which are not provided in detail for the sake of brevity; although the application has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the application.
Claims (4)
1. An RFID antenna virtual switch circuit is connected in series between an RFID reader and an antenna, and is characterized by comprising a triode T SWITCH Inductance L ISOLATE And diode D SWITCH The method comprises the steps of carrying out a first treatment on the surface of the The triode T SWITCH The emitter and the collector of the antenna are correspondingly connected with the RFID reader and the antenna respectively; the inductance L ISOLATE One end of the (E) is connected with the RFID reader, and the other end is connected with the RFID reader through a diode D SWITCH And triode T SWITCH Is connected with the base electrode of the transistor; an impedance matching circuit is connected between the virtual switch circuit and the RFID reader as well as between the virtual switch circuit and the antenna;
the triode T SWITCH The virtual switch circuit is in a conducting state when being closed so that the high-frequency radio frequency signals output by the RFID reader are transmitted to the antenna or the high-frequency signals received by the antenna are transmitted to the RFID reader, and is in a cutting-off state when being opened so that the high-frequency radio frequency signals output by the RFID reader cannot be transmitted to the antenna or the high-frequency signals received by the antenna cannot be transmitted to the RFID reader;
the inductance L ISOLATE For switching on diode D when the RFID reader outputs a low frequency or DC control signal SWITCH So that triode T SWITCH Cut-off, cut-off diode D when the RFID reader does not output a control signal SWITCH So that triode T SWITCH Conducting;
the diode D SWITCH For passing through inductance L ISOLATE Is rectified;
the RFID reader is used for outputting a control signal or a superposition signal of a high-frequency radio frequency signal and the control signal and receiving the high-frequency signal transmitted by the antenna;
the antenna is a transmitting antenna or/and a receiving antenna.
2. The virtual switch circuit of claim 1, wherein the diode D SWITCH And triode T SWITCH A delay circuit is arranged between the transistors for delaying the triode T SWITCH Switching state between on and off and for smoothing across diode D SWITCH A rectified signal; the delay circuit is a parallel resistor R SWITCH And capacitor C SWITCH 。
3. The virtual switching circuit of claim 1, wherein the impedance matching circuit is a capacitance-based matching bridge: between the virtual switch circuit and the RFID reader, a triode T SWITCH Through capacitor C MI1 Connected with RFID reader, capacitor C MI1 In parallel with capacitors C connected in series MI0 And capacitor C MI2 The method comprises the steps of carrying out a first treatment on the surface of the Between the virtual switch circuit and the antenna, a triode T SWITCH Through capacitance C MO1 Connected with the antenna, the capacitor C MO1 In parallel with capacitors C connected in series MO0 And capacitor C MO2 。
4. The virtual switch circuit of claim 1, wherein the transistor T SWITCH And inductance L ISOLATE The resistor R is also connected in series LIMIT 。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310847212.2A CN116582118B (en) | 2023-07-12 | 2023-07-12 | RFID antenna virtual switch circuit and multi-antenna multiplexing device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09215174A (en) * | 1996-02-09 | 1997-08-15 | Fms Audio Sdn Bhd | Power antenna output circuit for car audio |
| JP2003298334A (en) * | 2002-04-01 | 2003-10-17 | Sony Corp | Dielectric antenna apparatus and electronic equipment having the same |
| JP2004146916A (en) * | 2002-10-22 | 2004-05-20 | Fdk Corp | High frequency switch circuit and high frequency signal switch module |
| CN103632116A (en) * | 2013-11-22 | 2014-03-12 | 威海北洋电气集团股份有限公司 | Multi-path radio frequency antenna shifter and RFID (radio frequency identification) multi-antenna system |
| CN104598852A (en) * | 2015-01-08 | 2015-05-06 | 福建鑫诺通讯技术有限公司 | Discrete element circuit and method for realizing low-frequency RFID (radio frequency identification devices) label decoding |
| CN206725750U (en) * | 2017-03-09 | 2017-12-08 | 武汉大学 | A kind of VHF ionospheric irregularities detection system transmit-receive switch |
| CN109101853A (en) * | 2018-07-30 | 2018-12-28 | 成都九洲电子信息系统股份有限公司 | A kind of radio-frequency identification reader/writer system protection and antenna port detection system |
| CN208477536U (en) * | 2018-07-10 | 2019-02-05 | 上海汲深电子信息技术有限公司 | The read-write equipment of RFID electronic label |
| CN109344672A (en) * | 2018-09-19 | 2019-02-15 | 青岛贝威流体科技有限公司 | RFID identification circuit and pigeon racing RFID system |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8461964B2 (en) * | 2007-10-12 | 2013-06-11 | Commscope, Inc. Of North Carolina | Communications patching systems with radio frequency identification antenna switching circuits |
| US8558669B2 (en) * | 2009-04-12 | 2013-10-15 | Megabyte Ltd. | Radio frequency identification reader |
-
2023
- 2023-07-12 CN CN202310847212.2A patent/CN116582118B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09215174A (en) * | 1996-02-09 | 1997-08-15 | Fms Audio Sdn Bhd | Power antenna output circuit for car audio |
| JP2003298334A (en) * | 2002-04-01 | 2003-10-17 | Sony Corp | Dielectric antenna apparatus and electronic equipment having the same |
| JP2004146916A (en) * | 2002-10-22 | 2004-05-20 | Fdk Corp | High frequency switch circuit and high frequency signal switch module |
| CN103632116A (en) * | 2013-11-22 | 2014-03-12 | 威海北洋电气集团股份有限公司 | Multi-path radio frequency antenna shifter and RFID (radio frequency identification) multi-antenna system |
| CN104598852A (en) * | 2015-01-08 | 2015-05-06 | 福建鑫诺通讯技术有限公司 | Discrete element circuit and method for realizing low-frequency RFID (radio frequency identification devices) label decoding |
| CN206725750U (en) * | 2017-03-09 | 2017-12-08 | 武汉大学 | A kind of VHF ionospheric irregularities detection system transmit-receive switch |
| CN208477536U (en) * | 2018-07-10 | 2019-02-05 | 上海汲深电子信息技术有限公司 | The read-write equipment of RFID electronic label |
| CN109101853A (en) * | 2018-07-30 | 2018-12-28 | 成都九洲电子信息系统股份有限公司 | A kind of radio-frequency identification reader/writer system protection and antenna port detection system |
| CN109344672A (en) * | 2018-09-19 | 2019-02-15 | 青岛贝威流体科技有限公司 | RFID identification circuit and pigeon racing RFID system |
Non-Patent Citations (2)
| Title |
|---|
| 13.56 MHz RFID阅读器的多天线选通设计;蔡坚勇 林李金 郑华 陈银燕 朱雨;《无线电工程》;42-44 * |
| A Smart Cable Offering Selective and Distributed Antenna Radiation Using RF Switches and Non-Conventional Hybrid Couplers;Victoria Gómez-Guillamón Buendía;《 IEEE Transactions on Antennas and Propagation》;6346 - 6351 * |
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| CN116582118A (en) | 2023-08-11 |
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