HF RFID reader

Abstract

The utility model discloses an HF (High Frequency) RFID (Radio Frequency Identification Device) reader, which comprises a microcontroller MCU (Microprogrammed Control Unit) and a CLRC663 chip, the CLRC663 chip is connected with the microcontroller MCU, the microcontroller MCU is used for logic control and coordination of the HF RFID reader, the CLRC663 chip comprises a transmitter module TXMOD and a receiving demodulator RXDEMOD, the transmitter module TXMOD is used for modulation and transmission of RFID tag signals, and the receiving demodulator RXDEMOD is used for demodulation and receiving of the RFID tag signals. According to the utility model, the transmitter module TXMOD and the receiving demodulation RXDEMOD are integrated on the CLRC663 chip, so that the circuit design and layout of the HF RFID reader can be simplified, the size and the cost of the HF RFID reader are reduced, the performance of the HF RFID reader is improved, the power consumption of the HF RFID reader is reduced, and the possibility of signal loss and interference is further reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of RFID readers, in particular to a HF RFID reader. Background Art

[0002] In the 21st century, RFID technology is regarded as one of the most promising technologies, especially in the context of the rapid development of the Internet of Things. The research on key technologies of this technology has become a core element to promote the construction of the Internet of Things. At present, the main radio frequency protocols working in the 13.56Mhz frequency band (HF) are IS015693, IS015693 and IS014443A / B. Among them, ISO14443A and ISO15693 protocols are most widely used in industrial and production and life applications, while ISO14443B is more used in e-government scenarios related to ID cards. With the popularity of the new generation of smart phones, NFC function has become its standard configuration, and anti-counterfeiting traceability has become a typical application scenario of mobile phone NFC. However, the mass production of the production line has high requirements for the reading and writing distance of the reader. The normal reading and writing distance of the ISO14443A protocol is less than 10cm, and the normal distance of the ISO15693 protocol is less than 15cm. Therefore, the research on long-distance high-power readers based on the ISO14443A / ISO5693 standard communication protocol has important practical significance.

[0003] Existing solutions are mainly divided into three categories: long-distance single-protocol (ISO15693) readers that support anti-collision; long-distance single-protocol (ISO14443A) but do not support anti-collision; and medium- and short-distance dual-protocol readers that support anti-collision. This is mainly because there are large differences in the data rates of ISO14443A and ISO15693 and the bandwidth and gain of analog circuits. The circuits cannot be fully shared and need to be designed separately. In addition, in order to achieve the best reading distance and the highest efficiency, there are certain technical barriers to the design of anti-collision processes and algorithms. Therefore, research on long-distance high-power readers is necessary to meet the actual needs of the production line and promote the further development and application of RFID technology. Utility Model Content

[0004] The utility model provides a HF RFID reader to solve the problem that the RFID reader in the prior art cannot meet the long-distance reading and writing requirements of the application.

[0005] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0006] A HF RFID reader, comprising a microcontroller MCU and a CLRC663 chip;

[0007] The CLRC663 chip is connected to the microcontroller MCU, and the microcontroller MCU is used for logic control and coordination of the HF RFID reader. The CLRC663 chip includes a transmitter module TX_MOD and a receiving demodulator RX_DEMOD. The transmitter module TX_MOD is used for modulation and transmission of RFID tag signals, and the receiving demodulator RX_DEMOD is used for demodulation and reception of RFID tag signals.

[0008] Preferably, the HF RFID reader further comprises a directional coupler;

[0009] The directional coupler is connected to the antenna, and is used to separate the RFID tag return signal & carrier transmission signal sent and received by the antenna.

[0010] Preferably, the HF RFID reader further comprises an RX_analog front-end ceramic notch filter;

[0011] The RX_analog front-end ceramic notch filter is connected to the antenna, and the RX_analog front-end ceramic notch filter is used to perform carrier suppression on the received carrier.

[0012] Preferably, the HF RFID reader further comprises a ceramic filter;

[0013] One side of the ceramic filter is connected to the relay switching module, and the other side is connected to the analog switch. The ceramic filter is used to separate signals of different frequency bands to realize the identification and reading and writing of multi-protocol tags.

[0014] Preferably, the ceramic filter includes a 12.71 MHz ceramic filter and a 13.98 MHz ceramic filter;

[0015] The connection relationship between the 12.71 MHz ceramic filter and the 13.98 MHz ceramic filter is parallel, and different analog channels are switched in time division;

[0016] The 12.71 MHz ceramic filter is adapted to a signal rate of 14443A-106K, and the 13.98 MHz ceramic filter is adapted to a signal rate of 15693-26K.

[0017] Preferably, the HF RFID reader further comprises a power amplifier PA;

[0018] One side of the power amplifier PA is connected to the chip CLRC663, and the other side of the power amplifier PA is connected to the antenna;

[0019] The power amplifier PA is used to amplify the power of the radio frequency signal transmitted by the transmitter module TX_MOD.

[0020] Preferably, the HF RFID reader further comprises a detector;

[0021] One side of the detector is connected to the antenna, and the other side is connected to the microcontroller MCU. The detector is used to detect the parameters of the antenna.

[0022] Preferably, the number of the antennas is multiple;

[0023] Each of the multiple antennas is connected to a high-power PIN diode, and the high-power PIN diode is used to control the antenna switch to achieve fast switching of multiple antennas.

[0024] Preferably, the HF RFID reader further comprises an RX_analog front end AGC;

[0025] The RX_Analog Front End AGC is connected to the RX_Analog Front End ceramic notch filter, and the RX_Analog Front End AGC is used to adjust the signal processed by the RX_Analog Front End ceramic notch filter or the ceramic filter, and send the adjusted signal to the RX_Analog Front End balun.

[0026] Preferably, one side of the RX_analog front-end balun is connected to the RX_analog front-end AGC, and the other side of the RX_analog front-end balun is connected to the receiving demodulator RX_DEMOD. The RX_analog front-end balun is used to convert the received unbalanced signal into a balanced signal and then send it to the receiving demodulator RX_DEMOD.

[0027] Compared with the prior art, the beneficial effects of the utility model are:

[0028] The utility model HF RFID reader realizes efficient RFID signal processing by integrating microcontroller MCU, CLRC663 chip and other components. The CLRC663 chip integrates transmitter and receiving demodulator, which simplifies circuit design. Directional coupler and ceramic filter are used for signal separation and multi-tag identification. Power amplifier PA is used to amplify RF signal, while detector and high-power PIN diode are used for parameter detection and fast antenna switching. RX_Analog front-end AGC and balun further adjust the signal to ensure reception quality. This design is compact, efficient, low power consumption, and improves the reliability and flexibility of the system, which can realize long-distance reading and writing of RFID reader. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of the structure of an HF RFID reader of the utility model.

[0030] In the figure: 1. Microcontroller Unit MCU, 2. CLRC663 chip (high-performance short-range contactless card reader chip), 3. Transmitter module TX_MOD, 4. Power amplifier PA, 5. Detector, 6. Antenna, 7. High-power PIN diode, 8. Directional coupler, 9. RX_analog front-end ceramic notch filter, 10. 12.71mhz ceramic filter, 11. Relay switching module, 12. 13.98mhz ceramic filter, 13. Analog switch, 14. RX_analog front-end AGC, 15. RX_analog front-end balun, 16. Receive demodulator RX_DEMOD. DETAILED DESCRIPTION

[0031] The advantages and features of the present invention and the methods for achieving them will become apparent with reference to the embodiments described in detail below in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various forms. The present embodiments are provided only to complete the disclosure of the present invention and to enable those skilled in the art to fully understand the scope of the present invention, and the present invention is limited only by the scope of the claims. The same reference numerals represent the same constituent elements throughout the specification.

[0032] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] A HF RFID reader, comprising a microcontroller MCU and a CLRC663 chip;

[0034] The CLRC663 chip is connected to the microcontroller MCU, which is used for logic control and coordination of the HF RFID reader. The CLRC663 chip includes a transmitter module TX_MOD and a receiving demodulator RX_DEMOD. The transmitter module TX_MOD is used for modulation and transmission of RFID tag signals, and the receiving demodulator RX_DEMOD is used for demodulation and reception of RFID tag signals.

[0035] Preferably, the HF RFID reader further comprises a directional coupler;

[0036] The directional coupler is connected to the antenna, and is used to separate the RFID tag signals received and sent by the antenna.

[0037] Optionally, the HF RFID reader also includes an RX_Analog Front-End ceramic notch filter;

[0038] The RX_analog front-end ceramic notch filter is connected to the antenna, and the RX_analog front-end ceramic notch filter is used to perform carrier suppression on the received carrier.

[0039] Optionally, the HF RFID reader also includes a ceramic filter;

[0040] One side of the ceramic filter is connected to the relay switching module, and the other side is connected to the analog switch. The ceramic filter is used to separate signals of different frequency bands to realize the identification and reading and writing of multi-protocol tags.

[0041] Preferably, the ceramic filter includes a 12.71 MHz ceramic filter and a 13.98 MHz ceramic filter;

[0042] The connection relationship between the 12.71 MHz ceramic filter and the 13.98 MHz ceramic filter is parallel, and different analog channels are switched in time division;

[0043] The 12.71 MHz ceramic filter is suitable for the signal rate of 14443A-106K, and the 13.98 MHz ceramic filter is suitable for the signal rate of 15693-26K.

[0044] Preferably, the HF RFID reader further comprises a power amplifier PA;

[0045] One side of the power amplifier PA is connected to the chip CLRC663, and the other side of the power amplifier PA is connected to the antenna;

[0046] The power amplifier PA is used to amplify the power of the radio frequency signal transmitted by the transmitter module TX_MOD.

[0047] Preferably, the HF RFID reader further comprises a detector;

[0048] One side of the detector is connected to the antenna, and the other side is connected to the microcontroller MCU. The detector is used to detect the parameters of the antenna.

[0049] Preferably, the number of antennas is multiple;

[0050] Each of the multiple antennas is connected to a high-power PIN diode, and the high-power PIN diode is used to control the antenna switch to achieve fast switching of the multiple antennas.

[0051] Preferably, the HF RFID reader further comprises an RX_analog front end AGC;

[0052] The RX_Analog Front End AGC is connected to the RX_Analog Front End ceramic notch filter. The RX_Analog Front End AGC is used to adjust the signal processed by the RX_Analog Front End ceramic notch filter or the ceramic filter, and send the adjusted signal to the RX_Analog Front End balun.

[0053] Preferably, one side of the RX_analog front-end balun is connected to the RX_analog front-end AGC, and the other side of the RX_analog front-end balun is connected to the receiving demodulator RX_DEMOD. The RX_analog front-end balun is used to convert the received unbalanced signal into a balanced signal and then send it to the receiving demodulator RX_DEMOD.

[0054] For details, please refer to Figure 1 , Figure 1This is a schematic diagram of the structure of an HF RFID reader of the utility model. The utility model provides a technical solution: an HF RFID reader, including a microcontroller MCU1, a CLRC663 chip 2, a transmitter module TX_MOD3, a power amplifier PA4, a detector 5, an antenna 6, a high-power PIN diode 7, a directional coupler 8, an RX_analog front-end ceramic trap 9, a 12.71 MHz ceramic filter 10, a relay switch 11, a 13.98 MHz ceramic filter 12, an analog switch 13, an RX_analog front-end AGC 14, an RX_analog front-end balun 15, and a receiving demodulator RX_DEMOD 16. Among them, the CLRC663 chip 2 is connected to the microcontroller MCU1, and the microcontroller MCU1 can realize internal control of the HF RFID reader and control the operation of the entire HFRFID reader. Optionally, the microcontroller MCU1 can also be connected to an external electronic device and send the data obtained after the processing to the corresponding display module for display. The CLRC663 chip 2 includes a transmitter module TX_MOD3 and a receiving demodulator RX_DEMOD16. The transmitter module TX_MOD3 can send a corresponding RF signal to the power amplifier PA4 according to the instruction information sent by the microcontroller MCU1, wherein the power amplifier PA4 can be a class E power amplifier PA, which is a power amplifier suitable for RF applications and can amplify and transmit signals efficiently and reliably. The power amplifier PA4 is connected to the antenna 6, and the power amplifier PA4 can amplify the power of the RF signal sent by the transmitter module TX_MOD3, and then use the antenna 6 to send the amplified RF signal. The power of the power amplifier PA4 after amplification can be 50VP or other values. The number of antennas can be 4, and each antenna is connected to a high-power PIN diode. The high-power PIN diode 7 is used to control the antenna switch to achieve fast switching of multiple antennas. The antenna 6 is connected to the directional coupler 8, wherein the directional coupler 8 can be a directional coupler of the HF band, and the directional coupler of the HF band can be used to separate the radio frequency signal received by the antenna from the signal that the antenna needs to send, thereby increasing the anti-interference ability of the antenna 6. The antenna 6 is also connected to the detector 5, one side of the detector 5 is connected to the antenna 6, and the other side is connected to the microcontroller MCU1, and the detector 5 can be used to detect the parameters of the antenna 6, and the parameters of the antenna 6 may include the VSWR (voltage standing wave ratio) of the antenna 6. The antenna 6 is also connected to the RX_analog front-end ceramic trap 9, and the RX_analog front-end ceramic trap 9 is used to suppress the received carrier with strong carrier, which can effectively suppress the strong carrier signal so that it does not interfere with other signals, thereby ensuring better reception and recognition of the required signal.Optionally, the signals of different frequency bands can also be separated by a ceramic trap filter, and the ceramic filter includes a 12.71 MHz ceramic filter 10 and a 13.98 MHz ceramic filter 12. The connection relationship between the 12.71 MHz ceramic filter 10 and the 13.98 MHz ceramic filter 12 is parallel, and different analog channels are switched in time. The 12.71 MHz ceramic filter 10 is adapted to a signal rate of 14443A-106K, and the 13.98 MHz ceramic filter 12 is adapted to a signal rate of 15693-26K. The ceramic filter is also connected to a relay switching module 11 to control the switching of signals of different frequency bands. The relay switching module 11 can selectively connect or disconnect the signal paths of different frequency bands as needed, thereby realizing the identification and reading and writing of tags of different frequency bands. Through the control of the relay switching module 11, the HF RFID reader can flexibly adapt to tags of different frequency bands, thereby improving the compatibility and expansibility of the system. The other side of the ceramic filter is connected to the analog switch 13 for controlling the on and off of the signal. The RX_Analog Front End Ceramic Notch Filter 9 is connected to the RX_Analog Front End AGC14, which is connected to the RX_Analog Front End Balun 15. The RX_Analog Front End AGC14 is used to adjust the signal processed by the RX_Analog Front End Ceramic Notch Filter 9 or the ceramic filter, and send the adjusted signal to the RX_Analog Front End Balun 15. One side of the analog front end balun 15 is connected to the RX_Analog Front End AGC14, and the other side of the RX_Analog Front End Balun 15 is connected to the receiving demodulator RX_DEMOD16. The RX_Analog Front End Balun 15 is used to convert the received unbalanced signal into a balanced signal, and then send the processed signal to the receiving demodulator RX_DEMOD16. The receiving demodulator RX_DEMOD16 can send the processed signal to the microcontroller MCU1, and the microcontroller MCU1 can display the corresponding result on the electronic device connected to the microcontroller MCU1. Among them, it should be noted that the utility model can use standard ASIC to implement multi-protocol TX_Encode (transmitter encoding); use standard ASIC to implement RX_Decode (receiver decoding) multi-protocol processing and anti-collision algorithm processing; use standard ASIC integrated RX_analog (analog receiver) circuit to achieve mixing, intermediate frequency amplification, BB signal recovery; it has the advantages of high efficiency, low power consumption, high reliability, strong scalability, high integration, easy maintenance and upgrade, low cost and good electromagnetic compatibility.

[0055] Working principle: In the HF RFID reader, the operation of the entire system is controlled by the microcontroller MCU1. The microcontroller MCU1 sends the processed data to the corresponding display module for display through the connection with the external electronic device. It is also responsible for controlling the transmitter module TX_MOD3 and the receiving demodulator RX_DEMOD16 of the HF RFID reader to realize the internal control of the entire reader. The transmitter module TX_MOD3 sends the corresponding radio frequency signal according to the instruction information sent by the microcontroller MCU1. These signals are amplified by the power amplifier PA4 and then sent out through the antenna 6. The number of antennas can be 4, and each antenna is connected to a high-power PIN diode to control the antenna switch and realize the fast switching of multiple antennas. In this way, the reader can flexibly adapt to different communication needs and environmental conditions. The radio frequency signal received by the antenna 6 is first processed by the directional coupler 8. The function of the directional coupler 8 is to separate the radio frequency signal received by the antenna 6 and the signal that the antenna needs to send, thereby increasing the anti-interference ability of the antenna 6. Through the processing of the directional coupler 8, the reader can better identify and receive signals from different directions, improving the reliability and stability of communication. The detector 5 can be used to detect the parameters of the antenna 6, such as the voltage standing wave ratio (VSWR) of the antenna 6. By detecting the VSWR of the antenna 6, the matching degree between the antenna 6 and the transmission line can be understood, thereby judging the transmission state of the signal. If the VSWR is too high, it means that the matching between the antenna 6 and the transmission line is poor, which may cause reflection and loss of the signal. The detector 5 sends the detection result to the microcontroller MCU1, and the microcontroller MCU1 can adjust the communication parameters of the reader according to this information to ensure a good signal transmission effect. The signal processed by the directional coupler 8 and the detector 5 continues to be transmitted to the RX_analog front-end ceramic notch filter 9. The function of the RX_analog front-end ceramic notch filter 9 is to suppress the received carrier with strong carrier, which can effectively suppress the strong carrier signal so that it does not interfere with other signals, thereby ensuring better reception and recognition of the required signal. Through the processing of the RX_analog front-end ceramic notch filter 9, the reader can better extract the tag information and reduce the influence of noise interference. Optionally, signals of different frequency bands can also be separated by a ceramic filter. The ceramic filter may include a 12.71 MHz ceramic filter 10 and a 13.98 MHz ceramic filter 12, which are connected in parallel and switch different analog channels in time. The ceramic filter screens and processes the signal according to different frequency band characteristics and adapts to tag signals of different frequency bands. Through the control of the relay switching module 11, fast switching and selection of signals of different frequency bands can be achieved. In this way, the reader can flexibly adapt to tags of different frequency bands, improving the compatibility and scalability of the system. The processed signal is further controlled by the analog switch 13.The analog switch 13 selectively turns on or off the signal path according to the state of the control signal to realize the switch control of the signal. Through the control of the analog switch 13, the reader can better manage the transmission and processing flow of the signal. Finally, the signal processed by the RX_analog front-end ceramic notch filter 9 and the analog switch 11 is sent to the RX_analog front-end AGC14 for adjustment. After the RX_analog front-end AGC14 adjusts the signal, it is sent to the RX_analog front-end balun 15. The RX_analog front-end balun 15 converts the received unbalanced signal into a balanced signal, and then sends it to the receiving demodulator RX_DEMOD16. The receiving demodulator sends the processed signal to the microcontroller MCU1 for processing. The microcontroller MCU1 displays the processing results on the electronic devices connected to it. The user can view the operating status and tag information of the reader through these devices, thereby realizing the functions of identifying, suppressing, switching and modulating signals of different frequency bands, which helps to improve the performance and stability of the reader, and ensure reliable communication connection and accurate tag information reading, and realize long-distance reading and writing of RFID readers.

[0056] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention is described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A HF RFID reader, characterized in that: The HF RFID reader comprises a microcontroller MCU (1) and a CLRC663 chip (2); The CLRC663 chip (2) is connected to the microcontroller MCU (1), and the microcontroller MCU (1) is used for logic control and coordination of the HF RFID reader. The CLRC663 chip (2) includes a transmitter module TX_MOD (3) and a receiving demodulator RX_DEMOD (16), wherein the transmitter module TX_MOD (3) is used for modulation and transmission of RFID tag signals, and the receiving demodulator RX_DEMOD (16) is used for demodulation and reception of RFID tag signals.

2. The HF RFID reader according to claim 1, characterized in that: The HF RFID reader also includes a directional coupler (8) and an antenna (6); The directional coupler (8) is connected to the antenna (6), and the directional coupler is used to separate the RFID tag signals sent and received by the antenna.

3. The HF RFID reader according to claim 2, characterized in that: The HF RFID reader also includes an RX_analog front-end ceramic notch filter (9); The RX_analog front-end ceramic trap (9) is connected to the antenna (6), and the RX_analog front-end ceramic trap (9) is used to perform carrier suppression on a received carrier.

4. The HF RFID reader according to claim 1, characterized in that: The HF RFID reader also includes a ceramic filter; One side of the ceramic filter is connected to a relay switching module (11), and the other side is connected to an analog switch (13). The ceramic filter is used to separate signals of different frequency bands to realize the recognition and reading and writing of multi-protocol tags.

5. The HF RFID reader according to claim 4, characterized in that: The ceramic filter comprises a 12.71 MHz ceramic filter (10) and a 13.98 MHz ceramic filter (12); The 12.71 MHz ceramic filter (10) and the 13.98 MHz ceramic filter (12) are connected in parallel, and different analog channels are switched in time division; The 12.71 MHz ceramic filter (10) is adapted to a signal rate of 14443A-106K, and the 13.98 MHz ceramic filter (12) is adapted to a signal rate of 15693-26K.

6. The HF RFID reader according to claim 2, characterized in that: The HF RFID reader also includes a power amplifier PA (4); One side of the power amplifier PA (4) is connected to the CLRC663 chip (2), and the other side of the power amplifier PA (4) is connected to the antenna (6); The power amplifier PA (4) is used to amplify the power of the radio frequency signal transmitted by the transmitter module TX_MOD (3).

7. The HF RFID reader according to claim 2, characterized in that: The HF RFID reader further comprises a detector (5); One side of the detector is connected to the antenna (6), and the other side is connected to the microcontroller MCU (1). The detector (5) is used to detect parameters of the antenna (6).

8. The HF RFID reader according to claim 2, characterized in that: The number of the antennas (6) is multiple; Each antenna (6) in the multiple antennas (6) is connected to a high-power PIN diode (7), and the high-power PIN diode (7) is used to control the antenna switch to achieve rapid switching of multiple antennas.

9. The HF RFID reader according to claim 1, characterized in that: The HF RFID reader further comprises an RX_analog front end AGC (14) and an RX_analog front end balun (15); The RX_analog front end AGC (14) is connected to the RX_analog front end ceramic notch filter (9), and the RX_analog front end AGC (14) is used to adjust the signal processed by the RX_analog front end ceramic notch filter (9) or the ceramic filter, and send the adjusted signal to the RX_analog front end balun (15).

10. The HF RFID reader according to claim 9, characterized in that: One side of the RX_analog front-end balun (15) is connected to the RX_analog front-end AGC (14), and the other side of the RX_analog front-end balun (15) is connected to the receiving demodulator RX_DEMOD (16). The RX_analog front-end balun (15) is used to convert a received unbalanced signal into a balanced signal and then send it to the receiving demodulator RX_DEMOD (16).

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