Ultrahigh frequency RFID anti-interference system and method

Abstract

The invention relates to the technical field of RFID systems, in particular to an ultrahigh frequency RFID anti-interference system, which comprises a passive electronic tag, a reader-writer and a data processing system, and is characterized in that the passive electronic tag is arranged on the surface of an identified object; the environment temperature sensing module and the passive electronic tag are arranged in the same working environment, and the environment temperature sensing module is used for monitoring the temperature of the working environment; the reader-writer is provided with a temperature signal receiving device and a dynamic power adjusting module. The environment temperature sensing module can convert monitored temperature data into signals and send the signals to the temperature signal receiving device. The dynamic power adjusting module can adaptively adjust the radio frequency transmitting power of the reader-writer according to the input of the temperature signal receiver, thereby effectively solving the influence of the temperature on the work of the electronic tag, and improving the reliability and stability of the ultrahigh frequency RFID system in different temperature environments.

Description

Technical Field

[0001] The present invention relates to the technical field of RFID systems, and in particular to an ultra-high frequency RFID anti-interference system and method. Background Art

[0002] RFID systems (radio frequency identification) primarily consist of a reader / writer, an electronic tag, and a data processing system. When the reader / writer transmits a radio frequency signal of a specific frequency, the electronic tag receives it and converts the signal into electrical energy through its built-in antenna, activating its own circuits and enabling communication with the reader / writer.

[0003] Passive electronic tags are a common type of tag in RFID systems. They lack their own power source and rely entirely on the radio frequency signal emitted by the reader to operate. Their operating principle is as follows: when a passive electronic tag enters the reader's radio frequency field, the tag antenna senses the alternating magnetic field, generating an induced electromotive force in the antenna circuit, which in turn generates an induced current. This induced current, after processing through circuits such as rectification and voltage regulation, provides the necessary energy for the chip inside the tag.

[0004] It's worth noting that there's a close relationship between the induced current of an electronic tag and the ambient temperature. If the ambient temperature is too low, the performance of the tag's internal circuit components will be suppressed, resulting in a low induced current. This low current may not provide sufficient energy to the tag chip, causing the tag to malfunction, resulting in data transmission errors or failure to respond to reader commands. Simply increasing the reader's RF signal power will increase the induced current within the tag as the temperature rises, shortening the tag's lifespan.

[0005] In summary, in order to improve the reliability and stability of the UHF RFID system under complex environments such as temperature, it is of great practical significance to develop an effective UHF RFID anti-interference system and method. Summary of the Invention

[0006] The object of the present invention is to provide an ultra-high frequency RFID anti-interference system and method to solve the problems raised in the above background technology.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0008] An ultra-high frequency RFID anti-interference system includes a passive electronic tag, a reader / writer, and a data processing system. The passive electronic tag is set on the surface of the object to be identified.

[0009] It also includes an ambient temperature sensor module, which is set in the same working environment as the passive electronic tag to monitor the temperature of the working environment;

[0010] The reader is equipped with a temperature signal receiving device and a dynamic power adjustment module. The ambient temperature sensing module can convert the monitored temperature data into a signal and send it to the temperature signal receiving device.

[0011] The dynamic power regulation module can adaptively adjust the reader's RF transmission power according to the input of the temperature signal receiver.

[0012] Preferably, the reader is provided with an indicator light, and when the temperature signal receiving device receives the temperature signal sent by the ambient temperature sensing module, the indicator light lights up.

[0013] Preferably, the indicator light is a three-color LED light, which can switch to different colors of light according to the data received by the temperature signal receiver.

[0014] Preferably, the ambient temperature sensing module includes a temperature sensitive element, a signal conversion circuit and a wireless transmission device. The temperature sensitive element is used to sense the working environment temperature in real time. The signal conversion circuit converts the change in the resistance value of the temperature sensitive element into a temperature signal. The wireless transmission module sends the temperature signal to the temperature signal receiving device.

[0015] A UHF RFID anti-interference method includes the following steps:

[0016] The temperature sensor module monitors the temperature of the environment where the passive electronic tag is located in real time;

[0017] The temperature sensing module continuously sends the corresponding temperature data to the outside through signals;

[0018] When the reader enters the signal range of the temperature sensing module, the temperature signal receiving device receives the signal sent by the temperature sensing module;

[0019] The dynamic power regulation module adaptively adjusts the reader's RF transmission power according to the input of the temperature signal receiver.

[0020] As a preference, the dynamic power regulation module adopts a piecewise linear compensation algorithm to divide the operating temperature into three compensation intervals: low temperature compensation zone: -40℃≤temperature<0℃; normal temperature stability zone: 0℃≤temperature<25℃; high temperature attenuation zone: 25℃≤temperature≤85℃; each gear corresponds to a different RF power adjustment slope.

[0021] As a preference; (1) low temperature compensation area: reader power = W + (T + 40) × 1.2, where W is the reference power and T is the ambient temperature;

[0022] (2) Normal temperature stable zone: the reader power is constant at the reference power W;

[0023] (3) High temperature attenuation area: compensation formula P = W-(T-25) × 0.8, where W is the reference power and T is the ambient temperature.

[0024] The beneficial effects of the present invention compared to the prior art are as follows:

[0025] 1. The induced current of electronic tags is closely related to temperature, and temperature fluctuations can easily cause malfunctions. This invention incorporates an ambient temperature sensor module to monitor temperature in real time, and utilizes a dynamic power regulation module to adaptively adjust the reader's RF transmission power based on the temperature signal. Compared to traditional approaches that simply increase reader power without accounting for temperature fluctuations, this invention effectively mitigates the impact of temperature on electronic tag operation, improving the reliability and stability of UHF RFID systems in varying temperature environments.

[0026] 2. The reader is equipped with a three-color LED indicator light that switches colors based on the data received by the temperature signal receiver. This design allows operators to intuitively understand the current ambient temperature and system power regulation status, promptly identifying potential problems and greatly improving the system's monitorability and ease of use.

[0027] 3. The dynamic power adjustment module uses a piecewise linear compensation algorithm, dividing the operating temperature into a low-temperature compensation zone, a normal-temperature stability zone, and a high-temperature attenuation zone. Each zone corresponds to a different RF power adjustment slope. This scientific algorithm enables the system to precisely adjust the reader's RF transmit power according to different temperature ranges, achieving intelligent adaptive regulation. This meets the requirements for stable system operation in complex temperature environments and further improves the performance and stability of the UHF RFID system. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a principle flow chart of the UHF RFID anti-interference system of the present invention. DETAILED DESCRIPTION

[0029] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0030] The following is a specific embodiment of an ultra-high frequency RFID anti-interference system and method:

[0031] Embodiment 1:

[0032] This embodiment uses a refrigerator as an application scenario to demonstrate the construction and use of an ultra-high frequency RFID anti-interference system.

[0033] First, we select ultra-high frequency passive electronic tags suitable for the refrigerator environment. These tags have good low-temperature adaptability and are affixed to the surface of the food packaging that needs to be identified in the refrigerator. They are used to receive the radio frequency signal from the reader and feedback data.

[0034] A temperature sensing module is also installed within the refrigerator. This module uses a high-precision thermistor as a temperature sensor, placed on the inside wall of the refrigerator, ensuring accurate sensing of the low-temperature environment in which the electronic tag resides. The thermistor is connected to a signal conversion circuit based on the Wheatstone bridge principle, which accurately converts temperature-related changes in the thermistor's resistance into a voltage signal. A low-power, low-temperature stable Bluetooth module is used as the wireless transmission device to transmit the converted temperature signal wirelessly via Bluetooth. The entire ambient temperature sensing module is enclosed in a small, waterproof, low-temperature-resistant housing secured to the inside wall of the refrigerator.

[0035] The reader is equipped with a temperature signal receiver, which integrates a Bluetooth receiver module compatible with the ambient temperature sensor module. When a worker carrying the reader enters the designated work area, the Bluetooth receiver module stably receives temperature signals from low-temperature environments. The reader also includes a built-in microprocessor-based dynamic power regulation module, which adaptively adjusts the reader's RF transmission power according to a preset algorithm based on the temperature data input from the temperature signal receiver. When the passive electronic tag receives the RF signal from the reader, it is stimulated to generate an electric current, transmitting the corresponding product's digitally encoded RF signal to the reader.

[0036] In order to ensure that the reader power is adjusted more timely, the signal range of the temperature sensor module should be larger than the RF signal transmission range of the reader.

[0037] The data processing system consists of a server and corresponding data processing software. The server is connected to the reader through a wired network, receives the passive electronic tag data read by the reader and the temperature data transmitted by the ambient temperature sensor module, and stores, analyzes and processes it.

[0038] The reader is equipped with a three-color LED light as an indicator. The three-color LED light is connected to the temperature signal receiving device. The three-color LED light displays different colors according to the different temperature data received, providing intuitive feedback on the temperature status of the refrigerator. When the received temperature data is in the low temperature compensation zone (-40℃ ≤ temperature < 0℃), the LED light is blue; when it is in the normal temperature stability zone (0℃ ≤ temperature < 25℃), it is green.

[0039] The algorithm for the low-temperature compensation zone (-40°C ≤ < 0°C) is "Reader Power = W + (T + 40) × 1.2" (W is the reader's baseline power, the initial power automatically set when the reader is powered on; T is the temperature). This automatically adjusts the reader's RF transmit power. At this point, the tri-color LED lights blue, alerting staff to the low temperature inside the refrigerator. The presence of the tri-color LED indicates stable data communication between the passive tag and the reader.

[0040] In the normal temperature stable zone (0℃≤temperature<25℃), the algorithm is "reader power = W" (keeping the reference power unchanged), and the three-color LED light shows green.

[0041] Example 2:

[0042] This embodiment takes a storage warehouse in summer as an application scenario. Based on Example 1, it demonstrates the construction and use of the UHF RFID anti-interference system in a high temperature attenuation zone (25°C ≤ temperature ≤ 85°C).

[0043] Select ultra-high frequency passive electronic tags suitable for warehouse environments and stick them on the surface of goods that need to be identified in the warehouse, such as various electronic products and textiles, to receive the radio frequency signal of the reader and feedback data.

[0044] Temperature sensing modules are placed on warehouse shelves. When warehouse managers carry readers and work inside, they can stably receive temperature signals from the warehouse environment. The readers have a built-in microprocessor-based dynamic power regulation module. Based on the temperature data input from the temperature signal receiver, the reader's RF transmission power is adaptively adjusted according to a preset algorithm.

[0045] The three-color LED light on the reader will display red when the received temperature data is in the high temperature attenuation zone (25℃≤temperature≤85℃), intuitively feeding back to warehouse managers that the warehouse is in a high temperature state.

[0046] In the high-temperature attenuation zone, the reader power is adjusted according to the compensation formula "P = W - (T - 25) × 0.8" (where W is the reference power and T is the ambient temperature). For example, if the current warehouse temperature is T = 35°C and the reference power is set to W = 30dBm, the reader power is calculated to be P = 30 - (35 - 25) × 0.8 = 22dBm. The dynamic power adjustment module automatically adjusts the reader's RF transmit power to 22dBm. This power adjustment ensures that the passive electronic tag receives sufficient energy to operate normally in high-temperature environments while preventing excessive induced current from affecting the tag's service life due to temperature increases, thereby ensuring stable data communication between the passive electronic tag and the reader.

Claims

1. An ultra-high frequency RFID anti-interference system, comprising a passive electronic tag, a reader / writer, and a data processing system, wherein the passive electronic tag is disposed on the surface of an object to be identified; characterized in that: It also includes an ambient temperature sensor module, which is set in the same working environment as the passive electronic tag to monitor the temperature of the working environment; The reader is equipped with a temperature signal receiving device and a dynamic power adjustment module. The ambient temperature sensing module can convert the monitored temperature data into a signal and send it to the temperature signal receiving device. The dynamic power regulation module can adaptively adjust the reader's RF transmission power according to the input of the temperature signal receiver.

2. The UHF RFID anti-interference system according to claim 1, characterized in that: The reader is provided with an indicator light, which lights up when the temperature signal receiving device receives the temperature signal sent by the ambient temperature sensor module.

3. The UHF RFID anti-interference system according to claim 2, characterized in that: The indicator light is a three-color LED light, which can switch to different colors of light according to the data received by the temperature signal receiver.

4. The UHF RFID anti-interference system according to claim 1, characterized in that: The ambient temperature sensing module includes a temperature sensitive element, a signal conversion circuit and a wireless transmission device. The temperature sensitive element is used to sense the working environment temperature in real time. The signal conversion circuit converts the change in the resistance value of the temperature sensitive element into a temperature signal. The wireless transmission module sends the temperature signal to the temperature signal receiving device.

5. A UHF RFID anti-interference method, characterized by: The interference system according to any one of claims 1 to 4 is used, which comprises the following steps: The temperature sensor module monitors the temperature of the environment where the passive electronic tag is located in real time; The temperature sensing module continuously sends the corresponding temperature data to the outside through signals; When the reader enters the signal range of the temperature sensing module, the temperature signal receiving device receives the signal sent by the temperature sensing module; The dynamic power regulation module adaptively adjusts the reader's RF transmission power according to the input of the temperature signal receiver.

6. The UHF RFID anti-interference method according to claim 5, characterized in that: The dynamic power regulation module adopts a piecewise linear compensation algorithm to divide the operating temperature into three compensation ranges: low temperature compensation zone: -40℃≤temperature<0℃; normal temperature stability zone: 0℃≤temperature<25℃; high temperature attenuation zone: 25℃≤temperature≤85℃; each level corresponds to a different RF power adjustment slope.

7. The UHF RFID anti-interference method according to claim 6, characterized in that: (1) Low temperature compensation area: Reader power = W + (T + 40) × 1.2, where W is the reference power and T is the ambient temperature; (2) Normal temperature stable zone: the reader power is constant at the reference power W; (3) High temperature attenuation area: compensation formula P = W-(T-25) × 0.8, where W is the reference power and T is the ambient temperature.

Images