CN101937519A - RFID electronic tags that can be charged wirelessly - Google Patents

Abstract

The invention relates to a wirelessly chargeable RFID electronic tag, comprising a signal receiving antenna, a signal processing module, an energy receiving antenna, a rectifying circuit module and an energy storage capacitor, wherein the rectifying circuit module comprises a low pass filter, a matching circuit, a rectifier diode and a direct-pass filter, wherein one end of the low pass filter is directly connected with the energy receiving antenna and the other end is connected with the matching circuit; the matching circuit is connected with the direct-pass filter via the rectifier diode, the other end of the direct-pass filter is directly connected with the energy storage capacitor, the other end of the energy storage capacitor is directly connected with the signal processing module, and the signal processing module is connected with the signal receiving antenna. The RFID electronic tag capable of being charged in a wireless mode has the following benefits that the advantages of an active RFID such as long recognition distance, large transmission data amount, low emission power and high compatibility and the like are reserved, and the problem that the service life of the existing active RFID electronic tag depends on the service life of cells is eliminated. The wirelessly chargeable RFID electronic tag has wide application prospect.

Description

Translated fromChinese

可以无线充电的RFID电子标签RFID electronic tags that can be charged wirelessly

技术领域technical field

本发明涉及RFID技术领域，尤其涉及RFID电子标签。The invention relates to the technical field of RFID, in particular to an RFID electronic tag.

背景技术Background technique

射频识别(RFID)技术是一种非接触式的自动识别技术，它可以通过射频信号自动识别目标并获取所需数据。RFID电子标签是射频识别技术的核心，是射频识别系统真正的数据载体。Radio Frequency Identification (RFID) technology is a non-contact automatic identification technology, which can automatically identify targets and obtain required data through radio frequency signals. RFID electronic tag is the core of radio frequency identification technology and the real data carrier of radio frequency identification system.

RFID电子标签分为无源RFID电子标签和有源RFID电子标签两种。目前市场上主流的RFID电子标签是无源RFID电子标签。RFID electronic tags are divided into passive RFID electronic tags and active RFID electronic tags. At present, the mainstream RFID electronic tags on the market are passive RFID electronic tags.

无源RFID电子标签上不带电池，其工作所需要的全部电源都依靠转换接收到的读写器发送的射频能量而获得，其具体工作方式分为两种情况：对于高频RFID，基于电感耦合理论，无源RFID电子标签工作于读写器发射电磁场的近场区域，天线类似于变压器的耦合线圈，RFID电子标签的芯片与读写器通过天线线圈之间的耦合作用实现能量的传递；而超高频RFID，基于电磁场耦合理论，其电子标签工作于读写器发射电磁场的远场区域，天线可等效为一电流元，RFID电子标签芯片与读写器通过交变的电磁场实现能量的传递。上述两种情况下，接收天线两端产生了感应电势差，并在电子标签芯片通路中形成微弱电流，如果这个电流强度超过一个阈值，就将激活无源RFID电子标签的芯片电路工作，从而对标签芯片中的存储器进行读/写操作。但是因为读写器发射的射频能量有限，加之上述两种方式电能转换效率不高，所以无源RFID电子标签接收能量小，从而导致它的发射功率小，造成无源RFID识别距离短、传输数据量小、需要读写器发射功率大等缺点。并且因为无源RFID电子标签没有用于储能的结构，所以无源RFID电子标签芯片接收到的电能不能长期维持，只能一次性使用，降低了它的可靠性和兼容性。综上所述，现有的无源RFID电子标签虽然不需要自带电池，但是其识别距离短、传输数据量小、需要读写器发射更高的功率。There is no battery on the passive RFID electronic tag, and all the power required for its work is obtained by converting the received RF energy sent by the reader. The specific working methods are divided into two cases: for high-frequency RFID, based on inductance Coupling theory, passive RFID electronic tags work in the near-field area where the reader emits an electromagnetic field, and the antenna is similar to the coupling coil of a transformer. The chip of the RFID electronic tag and the reader realize energy transfer through the coupling between the antenna coil; UHF RFID, based on the electromagnetic field coupling theory, its electronic tag works in the far field area where the reader emits electromagnetic field, the antenna can be equivalent to a current element, the RFID electronic tag chip and the reader achieve energy through the alternating electromagnetic field transmission. In the above two cases, an induced potential difference is generated at both ends of the receiving antenna, and a weak current is formed in the electronic tag chip path. If the current intensity exceeds a threshold, the chip circuit of the passive RFID electronic tag will be activated to work, thereby protecting the tag. The memory in the chip performs read/write operations. However, because the radio frequency energy emitted by the reader is limited, and the power conversion efficiency of the above two methods is not high, the passive RFID electronic tag receives low energy, which leads to its low transmission power, resulting in short passive RFID identification distance and low transmission data. The disadvantages of small quantity and the need for high transmission power of the reader. And because the passive RFID electronic tag does not have a structure for energy storage, the electric energy received by the passive RFID electronic tag chip cannot be maintained for a long time and can only be used once, which reduces its reliability and compatibility. To sum up, although the existing passive RFID electronic tags do not need their own batteries, they have a short recognition distance, a small amount of transmitted data, and require higher power emitted by the reader.

有源RFID电子标签自身具备电池，可提供全部器件工作的电源，可以以较高的发射功率反馈信息，因而对读写器的发射功率要求不高，而且有效读写距离也较前者有所增加。可以说有源RFID电子标签具有识别距离远、传输数据量大、所需发射功率小、可靠性和兼容性好等优点。有源RFID电子标签虽然克服了无源RFID电子标签的不足，但是，有源RFID电子标签由于自带电源，故封装成卡片以后一般比较厚；其有源标签的价格较无源标签要昂贵；同时有源标签的寿命依赖于电池，一般在1～2年左右。正是因为这些不足，有源RFID技术发展相对滞后。The active RFID electronic tag has its own battery, which can provide the power supply for all devices, and can feed back information with a higher transmission power, so the requirements for the transmission power of the reader are not high, and the effective reading and writing distance is also increased compared with the former. . It can be said that active RFID electronic tags have the advantages of long recognition distance, large amount of transmitted data, small required transmission power, good reliability and compatibility. Although active RFID electronic tags overcome the shortcomings of passive RFID electronic tags, active RFID electronic tags are generally thicker after being packaged into cards because of their own power supply; the price of active RFID electronic tags is more expensive than passive tags; At the same time, the life of the active tag depends on the battery, generally about 1 to 2 years. It is precisely because of these shortcomings that the development of active RFID technology is relatively lagging behind.

发明内容Contents of the invention

本发明的目的是为了克服现有的有源RFID电子标签使用寿命依赖于自身电池的不足，提出了一种可以无线充电的RFID电子标签。The purpose of the present invention is to overcome the deficiency that the service life of the existing active RFID electronic tag depends on its own battery, and propose a wireless charging RFID electronic tag.

为了实现上述目的，本发明的技术方案提供了一种可以无线充电的RFID电子标签，包括信号接收天线和信号处理模块，其特征在于，还包括能量接收天线、整流电路模块和储能电容，所述整流电路模块包括低通滤波器、匹配电路、整流二极管和直通滤波器，所述低通滤波器的一端与能量接收天线直接连接，另一端与匹配电路连接，所述匹配电路通过整流二极管和直通滤波器连接，所述直通滤波器的另一端和储能电容直接连接，所述储能电容的另一端和信号处理模块直接连接，信号处理模块和信号接收天线连接。In order to achieve the above object, the technical solution of the present invention provides a wirelessly charged RFID electronic tag, including a signal receiving antenna and a signal processing module, and is characterized in that it also includes an energy receiving antenna, a rectifying circuit module and an energy storage capacitor. The rectification circuit module includes a low-pass filter, a matching circuit, a rectifier diode and a direct filter, one end of the low-pass filter is directly connected to the energy receiving antenna, and the other end is connected to the matching circuit, and the matching circuit passes the rectification diode and The pass-through filter is connected, the other end of the pass-through filter is directly connected to the energy storage capacitor, the other end of the energy storage capacitor is directly connected to the signal processing module, and the signal processing module is connected to the signal receiving antenna.

本发明专利的有益效果是：本发明的RFID电子标签技术改变了现有的有源RFID电子标签内自带电池供电的方式，通过自身的整流电路模块和储能电容实现了对RFID电子标签的无线输能并能将能量保存后以较高电压向信号处理模块供电，因此保留了有源RFID识别距离远、传输数据量大、发射功率小、可靠性和兼容性好等优点，同时又克服了现有的有源RFID电子标签使用寿命依赖于自身电池的不足，具有广泛的应用前景。The beneficial effect of the patent of the present invention is: the RFID electronic tag technology of the present invention changes the existing battery-powered mode of the active RFID electronic tag, and realizes the RFID electronic tag through its own rectification circuit module and energy storage capacitor. Wireless energy transmission and energy storage can be used to supply power to the signal processing module at a higher voltage, so it retains the advantages of active RFID, such as long identification distance, large amount of transmitted data, low transmission power, good reliability and compatibility, etc., while overcoming It solves the problem that the service life of the existing active RFID electronic tag depends on its own battery, and has a wide application prospect.

附图说明Description of drawings

图1是本发明的原理结构图。Fig. 1 is a schematic structure diagram of the present invention.

附图标记说明：信号接收天线1、信号处理模块2、整流电路模块3、储能电容4、能量接收天线5、电磁波9、低通滤波器31、匹配电路32、整流二极管33和直通滤波器34。Explanation of reference numerals:signal receiving antenna 1,signal processing module 2, rectifyingcircuit module 3, energy storage capacitor 4,energy receiving antenna 5,electromagnetic wave 9, low-pass filter 31,matching circuit 32, rectifyingdiode 33 anddirect filter 34.

具体实施方式Detailed ways

下面结合附图对本发明具体实施方式做进一步的说明。The specific embodiments of the present invention will be further described below in conjunction with the accompanying drawings.

如图1所示，一种可以无线充电的RFID电子标签，包括信号接收天线1和信号处理模块2、整流电路模块3、储能电容4和能量接收天线5，整流电路模块3包括低通滤波器31、匹配电路32、整流二极管33和直通滤波器34，低通滤波器31的一端与能量接收天线5直接连接，另一端与匹配电路32连接，匹配电路32通过整流二极管33和直通滤波器34连接，直通滤波器34的另一端和储能电容4直接连接，所述储能电容4的另一端和信号处理模块2直接连接，信号处理模块2和信号接收天线1连接。As shown in Figure 1, an RFID electronic tag that can be charged wirelessly includes asignal receiving antenna 1 and asignal processing module 2, a rectifyingcircuit module 3, an energy storage capacitor 4 and anenergy receiving antenna 5, and the rectifyingcircuit module 3 includes a low-pass filter 31, matchingcircuit 32, rectifyingdiode 33 and pass-throughfilter 34, one end of low-pass filter 31 is directly connected withenergy receiving antenna 5, and the other end is connected withmatching circuit 32, and matchingcircuit 32 passes through rectifyingdiode 33 and pass-throughfilter 34, the other end of the pass-through filter 34 is directly connected to the energy storage capacitor 4, the other end of the energy storage capacitor 4 is directly connected to thesignal processing module 2, and thesignal processing module 2 is connected to thesignal receiving antenna 1.

下面对本发明的工作原理做详细说明。本发明用于无线充电的电磁波采用S频段(2.45GHz)。首先，能量接收天线5接收电磁波9的射频能量并将能量转化成高频电流传送至整流电路模块3，整流电路模块3的低通滤波器31使工作频点的能量低插损通过并阻碍整流过程中产生的二次或更高次谐波通过能量接收天线5又辐射到自由空间去。然后，设置匹配电路32，连接整流二极管33。再连接由微带线和大电容组成的直通滤波器34后输出，其作用是只让直流通过，阻止基波和谐波通过。因此整流电路模块3内基频、二次和高次谐波就在低通滤波器31和直通滤波器34间来回反射，以提高射频能量转换为直流能量的效率。最后将直流能量送至储能电容4。储能电容4为信号处理模块2供电，信号处理模块2利用信号接收天线1与读写器之间进行非接触式双向通信，实现数据交换，以达到识别目的。The working principle of the present invention will be described in detail below. The electromagnetic wave used for wireless charging in the present invention adopts S frequency band (2.45GHz). First, theenergy receiving antenna 5 receives the radio frequency energy of theelectromagnetic wave 9 and converts the energy into a high-frequency current and transmits it to therectification circuit module 3. The low-pass filter 31 of therectification circuit module 3 allows the energy of the operating frequency point to pass through with low insertion loss and hinders rectification. The second or higher harmonic generated in the process is radiated to free space through theenergy receiving antenna 5 . Then, amatching circuit 32 is provided, and a rectifyingdiode 33 is connected. Then connect the pass-throughfilter 34 composed of microstrip line and large capacitor to output, its function is to only let the direct current pass through, and prevent the fundamental wave and harmonics from passing through. Therefore, the fundamental frequency, second and higher harmonics in therectification circuit module 3 are reflected back and forth between the low-pass filter 31 and the direct-pass filter 34 to improve the efficiency of converting radio frequency energy into direct current energy. Finally, the DC energy is sent to the energy storage capacitor 4 . The energy storage capacitor 4 supplies power to thesignal processing module 2, and thesignal processing module 2 uses thesignal receiving antenna 1 to perform non-contact two-way communication with the reader to realize data exchange and achieve the purpose of identification.

本发明中，能量接收天线5可以使用介电常数为4.7的FR_4的介质基板，厚度为0.6mm，天线尺寸40mm×40mm。经实验测得：中心频率2.45GHz，带宽为600MHZ，增益为2.17dB。In the present invention, theenergy receiving antenna 5 can use a FR_4 dielectric substrate with a dielectric constant of 4.7, a thickness of 0.6 mm, and an antenna size of 40 mm×40 mm. It is measured by experiments: the center frequency is 2.45GHz, the bandwidth is 600MHZ, and the gain is 2.17dB.

本发明中，能量接收天线5也可以采用介电常数为3.55的RO4003C介质基板，厚度为0.5mm，天线尺寸40mm×40mm。经实验测得：带宽900MHZ，增益为2.471dB，发生了频偏。In the present invention, theenergy receiving antenna 5 may also use a RO4003C dielectric substrate with a dielectric constant of 3.55, a thickness of 0.5mm, and an antenna size of 40mm×40mm. It is measured by experiments: the bandwidth is 900MHZ, the gain is 2.471dB, and frequency deviation occurs.

本领域的普通技术人员将会意识到，这里所述的实施例是为了帮助读者理解本发明的原理，应被理解为本发明的保护范围并不局限于这样的特别陈述和实施例。本领域的普通技术人员可以根据本发明公开的这些技术启示做出各种不脱离本发明实质的其它各种具体变形和组合，这些变形和组合仍然在本发明的保护范围内。Those skilled in the art will appreciate that the embodiments described here are to help readers understand the principles of the present invention, and it should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific modifications and combinations based on the technical revelations disclosed in the present invention without departing from the essence of the present invention, and these modifications and combinations are still within the protection scope of the present invention.

Claims (1)

Translated fromChinese

1.一种可以无线充电的RFID电子标签，包括信号接收天线和信号处理模块，其特征在于，还包括能量接收天线、整流电路模块和储能电容，所述整流电路模块包括低通滤波器、匹配电路、整流二极管和直通滤波器，所述低通滤波器的一端与能量接收天线直接连接，另一端与匹配电路连接，所述匹配电路通过整流二极管和直通滤波器连接，所述直通滤波器的另一端和储能电容直接连接，所述储能电容的另一端和信号处理模块直接连接，信号处理模块和信号接收天线连接。1. An RFID electronic tag that can be charged wirelessly, including a signal receiving antenna and a signal processing module, is characterized in that it also includes an energy receiving antenna, a rectifying circuit module and an energy storage capacitor, and the rectifying circuit module includes a low-pass filter, A matching circuit, a rectifying diode and a straight-through filter, one end of the low-pass filter is directly connected to the energy receiving antenna, and the other end is connected to the matching circuit, and the matching circuit is connected to the straight-through filter through the rectifying diode, and the straight-through filter The other end of the energy storage capacitor is directly connected to the energy storage capacitor, the other end of the energy storage capacitor is directly connected to the signal processing module, and the signal processing module is connected to the signal receiving antenna.

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