CN1975758A - Radio-frequency card or radio frequency label based on super wideband wireless pulse mode - Google Patents

Radio-frequency card or radio frequency label based on super wideband wireless pulse mode Download PDF

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CN1975758A
CN1975758A CN 200610165249 CN200610165249A CN1975758A CN 1975758 A CN1975758 A CN 1975758A CN 200610165249 CN200610165249 CN 200610165249 CN 200610165249 A CN200610165249 A CN 200610165249A CN 1975758 A CN1975758 A CN 1975758A
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circuit
data
signal
pulse
card
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CN100428263C (en
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张盛
刘萌萌
邢腾飞
张建良
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清华大学
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Abstract

The invention belongs to high speed RF card or RF label implementation technical area. Its characteristic is the non-symmetric information exchange, that is, use traditional standard sinusoidal carrier to transmit information and energy from card reader to RF card or RF label; use ultra-broadband pulse as information carrier to transmit data from RF card or RF label to card reader.

Description

基于超宽带无线脉冲方式的射频卡或射频标签 RF tags or RF card based on ultra-wideband wireless pulse method

技术领域 FIELD

:本发明涉及一种射频卡或射频标签的脉冲超宽带无线实现方案,在射频卡或射频标签和读卡器的通信中使用超高速,低功率谱密度的超宽带脉冲技术,具有电磁兼容性好,数据传输速率高,功耗低的特点,可进行简洁实用的电路设计和实现,易于芯片实现,属于短距无线通信和射频卡/射频标签领域。 : Relates to a radio card or radio tag UWB wireless implementations of the present invention, super high-speed communication in the radio card or radio frequency tags and readers, the low power spectral density of the pulsed ultra-wideband technology, electromagnetic compatibility , high data rate, low power consumption, can be simple and practical circuit design and implementation, is easy to chip, are short range wireless communication card and RF / RF tag area.

背景技术 Background technique

:脉冲超宽带技术是一种利用纳秒级的非正弦波脉冲传输数据的无线通信技术,它的信号频谱范围很宽,通常在500MHz以上,具有保密性强、抗干扰能力强和传输速率高等独特优势。 : UWB technique is a data transmission using a non-sinusoidal pulse nanosecond wireless communication technology, which signal spectrum is very wide range, typically in more than 500MHz, with confidentiality, anti-interference ability and high transmission rate Unique advantages.

美国联邦通信委员会(FCC)提出的关于超宽带的标准中指出,超宽带信号是指电磁波波形的相对能量带宽大于或等于0.2,或者有一个信号频宽大于或等于500MHz。 Federal Communications Commission (FCC) proposed UWB standards regarding stated, refers to ultra-wideband signal relative bandwidth of the electromagnetic wave energy is greater than or equal to 0.2, or a signal bandwidth is greater than or equal to 500MHz.

相对能量带宽的定义是,假定fL,fH分别是能量功率谱密度的下限频率和上限频率,即功率谱密度衰减10dB的两个频点,的那么中心频率为(fH+fL)/2,能量带宽为(fH-fL),相对能量带宽定义为能量带宽与中心频率的比值,即 The bandwidth is defined relative energy assumed fL, fH are the power spectral density lower limit frequency and upper limit frequency energy, power spectral density, i.e., two frequency attenuation of 10dB, then the center frequency (fH + fL) / 2, the energy bandwidth (fH-fL), the relative bandwidth is defined as the energy ratio of energy of the bandwidth center frequency, i.e., 射频智能卡是一种以无线方式传送数据的集成电路卡片,而射频标签是从射频卡的基础上发展起来的自动识别技术,两者都是通过射频信号的空间交变电磁场的耦合实现无接触信息传递,在数据处理,身份识别及物流控制等方面有广阔的应用。 RF smart card is an integrated circuit card for transmitting data in a wireless manner, the RF tag is automatic identification technology RF card on the basis of the up, both of which are coupled to an alternating electromagnetic field in contact-free spatial information through radio frequency signals transfer, have broad application in data processing, identification and logistics control and so on.

一个基本的射频卡/射频标签通信系统由三部分组成,如图1所示。 A basic RF card / radio-frequency tag communication system consists of three parts, as shown in FIG.

(1)射频卡/射频标签:由耦合元件及芯片组成,而每个射频卡或者射频标签具有唯一的电子编码,射频卡芯片通常封装为卡片形式使用,射频标签通常附着在物体上标识目标对象;(2)读卡器:读取射频卡或射频标签信息的设备,可设计为手持式或固定式;(3)天线:在射频卡或射频标签和读卡器间传递射频信号;按照能量供给形式,射频卡/射频标签系统可分为有源系统和无源系统。 (1) RF card / RF tags: the coupling components and chips, and each radio card or radio tag has a unique electronic code, radio frequency card chip package normally used in the form of a card, the RFID tag is generally attached to the object identification audiences ; (2) reader: RF card reading device or radio tag information, can be designed for handheld or fixed; (3) antenna: transmitting a radio frequency signal between the RF reader and RF tags or cards; according to their energy form supply, radio frequency card / RF tag system can be divided into passive systems and active systems.

所谓有源系统,就是通过标签内部的电池来供电,不需要读卡器提供能量来启动,标签可主动发射磁信号,识别距离较长,通常可达几十米甚至上百米,缺点是成本高,寿命有限,而且不易做成薄卡。 The so-called active systems, that is powered by an internal battery of the tag, the reader does not need to provide energy to start, the label may be active transmitter magnetic signal, the recognition distance is longer, typically up to tens of meters or even hundreds of meters, the disadvantage is the cost high, limited life, and difficult to make thin card.

无源系统的标签内部没有电池,其工作能量由读卡器发射的电磁场来提供,重量轻、体积小、寿命长、成本低,可制成各种卡片,是目前最流行的射频卡/射频标签形式。 Internal label passive system without a battery, its operating energy field emitted by the reader is provided, light weight, small size, long life, low cost, can be made of card, is the most popular card RF / RF label form. 其识别距离比有源系统要小,一般为几米到十米,而且需要较大的读卡器发射功率。 Which recognizes the active system is smaller than the distance, typically several meters to ten meters and requires a large transmission power of the reader.

目前的射频智能卡主要采用频率为13.56MHz和315MHz的连续正弦波作为能量传递和信息传递的媒介,新发展起来的射频标签技术也大量借鉴了目前的射频智能卡的技术方案。 The current radio frequency smart card is mainly used as a medium 13.56MHz and 315MHz passed as a continuous sine wave of energy and information delivery, the new developed RF tag technology also draws heavily on existing technical solutions RF smart card. 由于载波的频点低,同时受射频卡/射频标签功耗约束的限制,目前这两种应用的数据传输速率都相对较低,距离也不远(一般为几十厘米范围内,最大在10米距离内)。 Due to the low carrier frequency, while the limited RF card / tag RF power constraints, the current data transmission rate of the two is relatively low, also close (typically within a range of several centimeters, at maximum 10 Nemi distance). 未来的IC卡和射频IC卡将会存储和处理更多的信息内容,包括个人照片信息、视频信息和语音信息等,更高的安全要求也会提高加密密钥的长度,这就要求卡与读卡设备之间的数据传输速率进一步提高,同时保证卡上芯片的低功耗。 Future IC card and RF IC cards will store and process more information content, including personal photos information, video information and voice information, higher safety requirements will also increase the length of the encryption key, which requires card data transfer rate between the reader device further improved while maintaining low power consumption on a chip card. 新发展起来的脉冲超宽带无线技术非常适合这一应用。 Newly developed UWB wireless technology is ideal for this application.

发明内容 SUMMARY

:本发明的目的是提出采用脉冲超宽带无线技术实现射频智能卡和射频标签的技术方案,从射频卡/射频标签向读卡器的数据传输通信中采用超宽带脉冲作为信息载体,提高信息传输速率,降低功耗。 : Object of the present invention is to propose a pulsed ultra-wideband wireless technology aspect RF smart cards and RFID tag, ultra wideband pulses as an information carrier to a data transmission from the radio communication card in the card reader / RF tag, to improve the information transmission rate and lower power consumption.

本发明所述的整个射频卡/射频标签的结构如图2所示。 The entire structure of the RF card of the present invention / the RFID tag shown in Fig.

卡内部的芯片主要包括接收天线和解调器,低速的脉冲超宽带发射机(包括信道纠错编码器和脉冲调制发生器)、超宽带天线,以及根据应用需要设计的数据处理部分。 Card chip inside the receiving antenna and including a demodulator, low-speed UWB transmitter (including error correction encoder and a channel modulation pulse generator), ultrawideband antenna, and a data processing section depending on the application design. 由于脉冲超宽带技术具有电磁兼容性好、数据传输速率高、发射功率小、功耗低等优点,因此尤其适合在射频卡和射频标签中使用。 Since the pulse UWB electromagnetic compatibility, high data transmission rate, low transmission power, low power consumption, and therefore particularly suitable for use in the RF card and the RF tag. 但由于脉冲超宽带的接收机目前采用全数字相关接收方式,高速的数据采样和相关运算消耗较大的能量,同时信道纠错解码器所需要的电路面积和能量也远高于信道纠错编码器,我们采用非对称的信息交换方式,即从读卡器到射频卡/射频标签由传统标准的正弦载波进行信息传递,而从射频卡/射频标签向读卡器由超宽带脉冲信号进行信息传递。 However, since the UWB receiver is currently receiving full digital related embodiment, a high-speed data sampling and correlation operations consume more energy, while the circuit area and the error correction decoder channel energy required is much higher than the error correction channel coding device, we use asymmetric exchange of information, i.e., RF card from the card reader / RF tag information transmitted from the conventional standard sinusoidal carrier, and the information from the UWB pulse signal from the radio frequency card / reader to the RF tag transfer. 相应的,读卡器包含相应的超宽带接收机,对射频卡/射频标签发射的超宽带脉冲信号进行接收和解调。 Accordingly, the reader comprising a respective ultra wideband receivers, ultra wideband pulse signal RF card / RF tags receive and demodulate transmitted.

整个射频卡/射频标签主要包括接收机的模拟前端,数据存储和处理逻辑,超宽带脉冲调制发射器三个部分:(1)接收机的模拟前端主要用于还原接收到的信息,并提供卡或标签需要的电源、时钟等工作条件,主要包括接收天线,整流滤波电路,稳压电路,解调解码电路,时钟提取电路和复位信号产生电路。 Entire RF card / RF tag includes an analog front end, data storage and processing logic receivers, three ultra-wideband pulse modulator portion of the transmitter: (1) primarily for analog front end receiver to restore the received information, and to provide the card or tags require a power supply, a clock and other operating conditions, mainly includes a receiving antenna, a rectification filter circuit, voltage regulator circuit, a demodulation and decoding circuit, clock extraction circuit and the reset signal generating circuit. 分别用来接收数据和信号,产生卡或标签所需要的工作电压,稳定工作电压,对接收的信号进行解调解码以恢复原始信息,提取工作时钟,使卡或标签上电和掉电时复位;(2)数据存储和处理逻辑主要用于存储用户信息,并根据接收到的读卡器的信息将储存信息发出以做出应答;(3)超宽带脉冲调制发射器主要用于将卡或标签要发射的数据进行编码,调制并以脉冲的形式发射出去,包括和数据存储和处理部分的数据接口,信道编码器,脉冲调制发生器。 Reset respectively to receive the data signal and generating a card or a tag required operating voltage, voltage stability, demodulates the received signal decoded to recover the original information, the extraction operation clock, so that the card or the tag and power-down ; (2) primary data storage and processing logic configured to store user information, and based on the information received to store information sent to the reader in order to make the response; (3) ultra-wideband pulse modulator transmitter is mainly used for the card or tag data to be transmitted is coded, modulated and transmitted in the form of pulses, and comprising data storage and data interface, the channel coding processing section, a modulation pulse generator.

其中发射信号的超宽带频谱范围确定方法如下:采用FCC规定的3.1GHz~10.6GHz范围或较低的频谱范围,例如500MHz-1GHz。 Wherein the ultra-wideband transmit signal spectrum is determined as follows: using 3.1GHz ~ 10.6GHz lower spectral range or a predetermined range FCC, e.g. 500MHz-1GHz. 500MHz以上的扩频带宽获得的扩频增益较大,即使超宽带信号频段在400MHz到2.4GHz等常用的频谱范围内,由于脉冲超宽带本身的发射功率极低,射频卡/射频标签应用中的传输距离要求不高,通过链路预算知道,信号功率能保证与其他系统的电磁兼容性。 Spreading bandwidth of 500MHz or more to obtain large spreading gain, even if the ultra-wideband signal in a frequency band commonly used spectral range 400MHz to 2.4GHz and the like, since the UWB transmitter itself very low power, radio frequency card / RF tag applications transmission distance less demanding, known by the link budget, the signal power to ensure electromagnetic compatibility with other systems.

本发明采用脉冲超宽带无线技术实现的射频智能卡和射频标签,采用非对称的信息交换方式,即从读卡器到射频卡/射频标签由传统标准的正弦载波进行信息和能量的传递,从射频卡/射频标签和读卡器的数据传输通信中采用超宽带脉冲作为信息载体,克服了传统采用频率为13.56MHz或315MHz的连续正弦波传递信息的方案具有的数据传输速率低,功耗较高,电磁兼容性较差等缺点,利用超宽带信号的特点提高了电磁兼容性,信息传输速率,降低了功耗。 The present invention uses smart cards and RF tags UWB wireless RF technology, the asymmetric exchange of information, i.e., RF card from the card reader / RF tag for transmitting information and energy by the conventional standard sinusoidal carrier, from a radio frequency communication card used in the data transmission / radio frequency tag reader and ultra-wideband pulses as an information carrier, to overcome the traditional use of a low frequency of 13.56MHz or 315MHz sine wave of a continuous transmission of information has the data transmission rate, high power consumption , disadvantages such as poor electromagnetic compatibility, the use of ultra-wideband signal characteristics to improve electromagnetic compatibility, the information transmission rate, power consumption is reduced. 同时,这种方案简洁实用,易于电路实现和芯片集成。 At the same time, this solution is simple and practical, easy to implement and the circuit chip integration.

附图说明 BRIEF DESCRIPTION

:图1是基本的无源射频卡/射频标签结构。 : FIG. 1 is a basic passive RF card / RF tag structure.

图2是采用脉冲超宽带无线技术的无源射频卡/射频标签结构。 FIG 2 is a pulsed ultra-wideband wireless technology passive RF card / RF tag structure.

图3是50%ASK调制信号图。 FIG 3 is a 50% ASK modulated signal of FIG.

图4是二极管整流滤波电路。 FIG 4 is a diode rectifier filter circuit.

图5是电压转换和稳压电路。 FIG 5 is a voltage converter and regulator circuit.

图6是反相器交叉耦合的时钟提取电路。 The clock extraction circuit 6 is a cross-coupled inverters.

图7是包络检波流程图。 FIG 7 is a flowchart of the envelope detector.

图8是一种简单的从包络获得数据的电路结构。 FIG 8 is a simple circuit configuration is obtained from the data envelope.

图9是数据存储和处理结构示意图图10是PPM调制发射流程图。 9 is a schematic structural diagram of a data storage and processing of FIG. 10 is a flowchart PPM modulated transmission.

图11是脉冲发射器功能示意图。 FIG 11 is a functional schematic diagram of the transmitter pulse.

图12是一种类似数字电路结构的脉冲发生器。 FIG 12 is a similar digital pulse generator circuit configuration.

具体实施方法:本发明提出的采用脉冲超宽带无线技术实现射频智能卡和射频标签的技术方案,其所对应的射频卡/射频标签主要由接收机的模拟前端,数据存储和处理部分,超宽带脉冲调制发射器三个部分组成,分别用模拟电路,数字电路和数模混合电路实现。 DETAILED DESCRIPTION Methods: UWB RF wireless smart card technology and the technical solution proposed RFID tag of the present invention, its corresponding card RF / analog front end radio frequency tag mainly by the receiver, and the data storage processing section, ultra wideband pulses three modulation transmitter portion, namely with analog circuitry, digital circuitry and digital-analog mixed circuit implementation. 射频标签/射频卡的结构图如图2所示。 FIG RF tag configuration / RF card shown in Figure 2. 首先,接收机的模拟前端通过接收天线通过电磁场耦合从读卡器接收数据和能量,其中能量通过整流滤波和稳压之后提供整个卡或标签的工作电压,数据通过解调解码器还原为原始信息。 First, the analog front end receiver, wherein the working voltage across the energy provided by a card or a tag and the constant voltage after the rectifier filter data received from the card reader and energy by electromagnetic coupling through the receiving antenna, to restore the original information data by demodulating decoder . 另外,时钟提取部分从接收到的正弦波中提取同频时钟,提供给数字部分使用,复位信号产生部分在卡或标签上电和掉电时输出复位信号,保证卡或标签的正常工作。 Further, the clock extraction section extracts from the received sine wave with the frequency-divided clock is supplied to the digital part of the use, the reset signal generating portion outputs a reset signal and a power-down on the card or a tag, to ensure the normal operation of a card or a tag. 然后,经过解调解码后的数据进入数字存储和处理部分,根据接收到的信息确定要发回的应答信息,最后,发射信息经过数据接口,信道编码器后通过脉冲调制发生器向读卡器发射带有信息的符合超宽带定义的脉冲信号。 Then, after decoding the demodulated data into the digital storage and processing section, the received information to determine response information to be sent back according to the last, after the data interface to transmit information, the channel encoder to the reader by modulating a pulse generator transmission pulse signal with information meet ultra-wideband definition.

以下结合附图,详细介绍本发明的内容:接收机模拟前端:读卡器向射频卡/标签发射的数据可以采用多种调制方式,不同的调制方式会影响模拟前端的一些具体设计,但是整体结构是不变的。 In conjunction with the following drawings, detailed description of the present invention: a receiver analog front end: the data transmitted to the RF card reader / tag may use a variety of modulation, different modulation modes affect some specific design of the analog front end, but the overall structure is unchanged. 本发明认为读卡器向射频卡/标签发射的数据采用50%的ASK(幅度键控)调制。 The inventors believe that the data transmitted to the radio frequency card reader / tag with 50% of ASK (amplitude shift keying) modulation.

图3是50%ASK调制后的波形。 FIG 3 is a waveform after the 50% ASK modulation. 其中调制指数m=(ab)/(a+b)=50%。 Wherein the modulation index m = (ab) / (a ​​+ b) = 50%.

接收机的模拟前端包括图2中的接收天线,整流滤波电路,电压转换稳压电路,时钟提取电路,复位信号产生电路和解调电路。 The analog front end receiver includes a receiving antenna in FIG. 2, rectifier and filter circuit, a voltage conversion regulator circuit, clock extraction circuit, the reset signal generating circuit and a demodulation circuit. 接收天线利用电磁场的耦合从读卡器接收正弦波信号,接收信号内包含的读卡器发送的数据,同时也接收了能量。 Reception antennas using an electromagnetic field coupled to receive a sinusoidal signal from the card reader, the reader of data contained within the received signal transmitted and also received energy. 接收到的正弦波经过整流滤波电路得到直流电压,经过电压转换和稳压电路得到模拟电路所需的工作电压和数字电路所需的工作电压。 The received sine wave rectified DC voltage filtering circuit, and the converted voltage regulator circuit to obtain the desired operating voltage required for the analog circuits and digital circuits operating voltage. 接收到的正弦波同时通过解调解码电路得到读卡器发送的原始信息,并通过时钟提取电路得到正弦波的同频时钟,供数字电路使用。 Sine wave received simultaneously obtain the original information transmitted by the reader demodulation and decoding circuit, and the sine wave obtained by the clock extraction circuit with a clock frequency for the digital circuitry. 此外,为了保证整个芯片的正常工作,需要通过复位信号产生电路在上电和掉电时分别输出一个复位信号。 Further, to ensure the normal operation of the chip, the reset signal needs to be generated by the circuit outputs a reset signal on power up and power-down.

以下简要介绍模拟前端各部分的实现方法:(1)接收天线:用来通过电磁场耦合接收数据和能量。 Implementation The following summarizes the various parts of the analog front end: (1) receive antennas: means for receiving data by electromagnetic coupling and energy. 调节天线的阻抗值L和C,使其在正弦波信号频率处发生谐振,从而使接收到的能量最强。 Adjust the antenna impedance value L and C, so that resonance occurs at a frequency of the sine wave signal, so that the energy of the strongest received. 谐振频率由如下公式给出:f=2π1LC·]]> Resonance frequency is given by the following equation: f = 2 & pi; 1LC & CenterDot;]]>

(2)整流滤波电路:由于射频卡/射频标签本身没有电源,为了给各部分模拟和数字电路提供工作所需的各种电源,必须从天线接收到的信号中提取能量,并转换成稳定的直流电源。 (2) rectifying and filtering circuit: Since the RF card / RF tag itself has no power signal, to provide various desired operating power to the components of the analog and digital circuits, must be received from the antenna to extract energy and convert it into a stable DC power supply. 而接收到的信号是交流正弦波,所以首先要经过整流滤波电路将其转换成直流信号。 The received AC signal is a sine wave, through the first rectifying and filtering circuit converts it into a DC signal. 整流电路的实现方法很多,例如图4所示的简单二极管整流滤波电路。 Many rectifier circuit implementation, such as a simple diode rectifier filter circuit 4 shown in FIG.

如图4所示,天线的两端通过两个二极管连通到一个电容C上,无论在A端电压的正半周还是B端电压的正半周,天线通过二极管对C充电,这样C上会存在一个稳定的直流电压Vdc,Vdc的值等于天线电压的有效值减去一个二极管的阈值,即:VHD=V12-VTN]]>其中V1为天线两端电压的峰值,VTN为二极管的阈值电压。 4, the two ends of the antenna communicates through a diode to the capacitor C, both in a positive half cycle voltage of the A or B end of the positive half cycle voltage of the antenna C is charged through the diode, there will be on such a C stable DC voltage Vdc, Vdc is equal to the RMS value of the antenna minus the threshold voltage of a diode, namely: VHD = V12-VTN]]> where V1 is the peak voltage across the antenna, VTN is the threshold voltage of the diode.

(3)电压转换和稳压电路:整流滤波电路将交流信号转换成一定幅值的直流信号,但是各部分的模拟电路和数字电路所需要的工作电压是不同的,而且直接由整流电路提供的直流电平不稳定,所以需要电压转换和稳压电路,将整流输出的直流电平变换到所需的各种直流电压,并通过反馈机制使电压稳定。 (3) converting the voltage regulator circuit and: rectifier filter circuit converting AC signal into a DC signal of constant amplitude, but the analog and digital circuitry portions required operating voltage is different, but also directly by the rectifying circuit DC level instability, and it is necessary to convert the voltage regulator circuit, the DC output level of the rectified DC voltage is converted to a variety of desired, and the voltage is stabilized by a feedback mechanism. 电压转换和稳压电路有多种实现方法,例如图5所示的一种利用负反馈的电压转换和稳压电路。 Voltage conversion and regulation circuits implemented in many methods, for example, one voltage conversion circuit and a negative feedback regulator using FIG. 5.

如图5所示,电压转换和稳压电路的基本思想是对输出电压进行采样,然后跟参考电压比较,用误差放大器把这个变化反映到调整管的输入,实现一定范围内,例如1-5V的稳压输出。 As shown, the basic idea of ​​converting the voltage regulator circuit and the output voltage is 5 samples, are then compared with the reference voltage by an error amplifier to reflect the change to the input of the regulator, to achieve within a certain range, for example 1-5V regulated output. 实际电路实现中,参考电压REF用几个MOS管的阈值电压相加得到,而输出电压Vout和参考电压REF的比例固定在(R1+R2)/R2,这样通过调节R1,R2和REF能得到所需要的电压值Vcc,Vdd,公式如下所示。 The actual circuit implementation, the reference voltage REF threshold voltage obtained by adding the number of MOS transistors, the output voltage Vout and the reference voltage REF and the ratio is fixed (R1 + R2) / R2, so that by adjusting R1, R2 and REF can be obtained FIG desired voltage Vcc, Vdd, the following formulas.

VOUT=VREF(R1+R2R2)]]>以上电路所得到的输出电压不可能高于输入的直流电压,即如果需要的直流电压高于整流滤波后的直流电压Vdc,,上述电路是无效的。 VOUT = VREF (R1 + R2R2)]]> obtained above circuit output voltage is higher than the input DC voltage is impossible, i.e., if the DC voltage is required higher than the DC voltage Vdc rectified filtered ,, said circuit is invalid. 这时需要通过电荷泵来得到更高电压值的稳定电压。 In this case a higher voltage is necessary to obtain a stabilized voltage by a charge pump.

(4)时钟提取电路:数字电路的正常工作需要一定频率的时钟信号,射频卡/射频标签本身对于较低的频率的信号,如13.56MHz的信号,直接将正弦信号放大后整形得到方波以提供时钟信号。 (4) the clock extraction circuit: the clock signal is normal operation of the digital circuit requires a certain frequency, radio frequency card / tag itself, the RF signal to a lower frequency, such as the signal of 13.56MHz, directly obtained after amplification and shaping the sinusoidal signal to a square wave It provides a clock signal. 时钟提取电路有多种实现形式,例如图6所示的通过交叉耦合的反相器得到同频率全摆幅方波信号的电路。 Clock extraction circuit implemented in many forms, such as a circuit with the frequency of the full-swing signal is a square wave obtained by cross-coupled inverters shown in Fig.

天线两端的信号进入一个放大器,放大器以两个交叉耦合的反相器作为负载,这样不仅增大了放大器的负载,同时对输出信号整形,使时钟信号的跳变沿理想。 A signal amplifier into the antenna ends, two cross-coupled amplifier inverter as a load, so that not only increases the load of the amplifier, the output signal while shaping the jump over the edge of the clock signal becomes.

对于工作在更高频率的射频卡/射频标签,这种时钟提取方法失效,必须采用窄带锁相环路来提取时钟,这样会增大电路的功耗和复杂度。 For work at higher frequency RF card / radio frequency tag, this clock extraction method fails, the narrowband phase-locked loop must be used to extract a clock, and this will increase the complexity of the circuit power.

(5)复位信号产生电路:射频卡/射频标签的数字电路部分存在大量内部触发器,这些触发器在上电的时候需要初始化复位,这就需要上电时提供一个复位信号,并且在电源电压稳定后再消失。 (5) the reset signal generating circuit: the presence of a large number of internal trigger digital circuitry of the RF card / RFID tag, these triggers need to be initialized at power up reset, a reset signal which provides the required power, and the power supply voltage stabilize and then disappear. 另外,由于一些诸如卡不慎落地的原因,电源电压下降,这会导致驱动能力下降,从而对电路工作带来影响,造成数据混乱。 In addition, due to some reasons such as accidentally landing card, power supply voltage drop, which can lead to decreased driving ability, leading to impact on the circuit, resulting in data confusion. 所以为了导致电路不受低压的破坏,必须提供低压保护信号,等待电源电压恢复正常后再取消。 So in order to cause a low pressure circuit from damage, it must provide a low-voltage protection signal, wait for the supply voltage returns to normal after the cancellation.

(6)解调电路:由于读卡器发射信号的调制方式为幅度调制,故采用检测包络的方法来进行解调。 (6) demodulation circuit: Since the reader transmit modulation signal is an amplitude modulation, so the use of an envelope detection method to demodulate. 虽然信号中存在载波分量,一种解调方案是提取载波后进行相干解调,但为了降低功耗和复杂度,采用比较简单的包络解调方法。 Although there is a signal carrier component in a coherent demodulation scheme is demodulated to extract the carrier, in order to reduce power consumption and complexity, using a relatively simple envelope demodulation method. 如图7所示是一种包络检波的流程图。 As shown is a flowchart of an envelope detector 7 shown in FIG.

n(t)是信号传输过程中的噪声,带通滤波器恰好使调幅信号完整通过,检波后输出其包络,数据判决器通过对基带包络的处理恢复二进制数据数据,恢复出数字序列。 n (t) is the signal transmission noise, the band pass filter is just that the amplitude modulated signal to pass intact, the output of the envelope after detection, data decision recovers the binary data by processing baseband envelope to recover the sequence of numbers. 带通滤波器有多种实现方式,例如采用简单的RLC网络,包络检波器采用简单的RC检波电路,而数据判决器没有采用比较复杂的A/D采样判决,而是根据ASK信号的特点,通过简单的设定阈值的反相器来获得包络代表的二进制信息。 Bandpass filter implemented in many ways, for example by simple RLC network, an envelope detector using a simple RC detection circuit does not use the data decision more complex A / D sampling decision, but ASK signal according to the characteristics to obtain an envelope represented by a simple inverter set threshold binary information. 如图8所示。 As shown in FIG.

包络信号送入第一级反相器进行整形,使包络线的上升下降沿变得陡峭。 Envelope signal fed to the first stage inverter for shaping the rising and falling edges of the envelope becomes steeper. 这个反相器的翻转电平VM在0和1分别对应的ASK调制信号两幅值a和b的中间,如图3所示。 Flip-level inverter in the VM 0 and 1 ASK modulated signal corresponding to each of two intermediate values ​​a and b, as shown in FIG. 信号通过一级反相整形后,再通过交叉耦合单元进行数据存储,最后送入一级反相器恢复波形,输出数据。 Signal, then the data storage unit by the cross-coupling through an inverted plastic, and finally fed to a recovery waveform of the inverter output data.

数据存储和处理逻辑:采用普通的数据存储和处理结构,即由MCU,RAM,FLASH和I/O接口组成,由MCU统一调度数据,发出指令。 Data storage and processing logic: the ordinary data storage and processing structure, i.e. by the MCU, RAM, FLASH, and I / O interface, of a unified MCU data, issues an instruction. 如图9所示。 9 shown in FIG.

模拟前端解调出的数据经过I/O接口进入MCU,由MCU根据输入数据发出指令,从FLASH读取存储的信息,并进行运算,最后将应答信息经过I/O接口发射出去。 Analog data demodulated through the front end I / O interface into the MCU, the data sent by the MCU according to an input instruction, reads the stored information from the FLASH, and operation, and finally the response information via I / O interface emitted.

MCU,RAM,I/O接口用单片机实现,如Synopsys公司的dw8051,外挂的FLASH使用ST公司的M25P40。 MCU, RAM, I / O interfaces with MCU, such as Synopsys, Inc. dw8051, FLASH plug using ST's M25P40.

超宽带脉冲调制发射器:超宽带脉冲调制发射器结构包括数据接口,信道编码器,脉冲调制发生器和发射天线,如图2所示。 UWB pulse modulation transmitter: UWB pulse modulation transmitter comprises a data interface structure, a channel encoder, the modulation pulse generator and a transmit antenna, as shown in FIG. 需要发射的数据经过数据接口进入由信道编码器,编码后的信号控制脉冲调制发生器经过超宽带天线发射出带有信息的脉冲信号。 Data needs to be transmitted via a data interface enters the channel encoder, encoded signal modulated control pulse generator via ultrawideband antenna transmit pulse signals with information. 其中数据接口,信道编码器用数字电路实现,脉冲调制发生器用模拟电路实现。 Wherein the data interface, the channel encoder digital circuitry, analog pulse modulation generator circuitry.

(1)数据接口:数据接口的作用是接收数据存储和处理逻辑决定要发射的数据,并将其传至数字编码电路。 (1) Data Interface: effect data interface is a data storage and processing logic receives data to be transmitted is determined, and transmitted to the digital coding circuit. 数据接口的实现取决于射频卡/射频标签和读卡器之间通信所定义的数据格式。 Data interface implementation depends on the format of the communication data between the RF card / tag and RF reader as defined above.

(2)信道编码器:在通信系统中,差错的主要来源是噪声、衰落、干扰。 (2) the channel coder: in a communication system, the major source of error is noise, fading, interference. 为保证足够低的差错率,最根本的方法是采用差错控制编码,亦称信道编码。 In order to ensure a sufficiently low error rate, the most fundamental way is to use error control coding, also known as channel coding. 其本质是给发送的信息字引入冗余,将信息空间I映射到更大的信道空间S,提高信道空间中不同码字间的差异程度,使得接收的码字错成另一许用码字的概率降低,获得编码增益。 Its essence is the code word transmitted to the information word redundancy is introduced, the spatial information mapped to the I channel larger space S, the degree of increase in the channel spacing differences between different codewords, such that the received allowable error into another codeword reduce the probability to obtain coding gain. 编码的类型很多,例如低密度奇偶校验(LDPC)码等。 Many types of coding, such as low density parity check (LDPC) codes.

(3)脉冲调制发射器:超宽带脉冲信号的调制方式有多种调制方式,例如脉冲位置调制(PPM)方式,但不限于PPM调制。 (3) a pulse modulated transmitter: There are many UWB pulse modulation signal modulation scheme such as pulse position modulation (PPM) mode, but is not limited to a PPM modulation.

脉冲位置调制(Pulse Position Modulation,缩写为PPM)是一种改变脉冲出现时间的调制方式,这种方式在传统的连续波中是没有的。 Pulse position modulation (Pulse Position Modulation, abbreviated to PPM) is a time to change the modulation pulse occurs in the conventional way this is not a continuous wave. 其时域表达式为:s(t)=Σj=∞∞p(t-jTf-djTC)]]>其中p(t)是t时刻的脉冲,{dj}是调制序列,Tf为脉冲序列的周期,TC是单位偏移量。 The time domain expression is: s (t) = & Sigma; j = & infin; & infin; p (t-jTf-djTC)]]> where p (t) is a pulse at time t, {dj} is the modulation sequence, Tf for the period of the pulse sequence, TC is the unit offset. s(t)为一系列以jTf为基准,偏移量为djTC的脉冲。 s (t) into a series jTf as a reference offset djTC pulse.

PPM调制的实现方法如图10所示。 PPM modulation implementation is shown in Fig.

将信息dj作为偏移量控制脉冲发射器,产生出不同位置的脉冲,脉冲的位置作为信息载体。 Dj offset information as the control pulse emitter, to generate a position different pulse positions, pulse as an information carrier.

如果脉冲可分辨的位置有N个,那么一个脉冲最多能用来调制log2N比特的信息,这样就能达到较高的信息传输速率。 If the pulse position can be distinguished with N, then up to a pulse log2N bits used to modulate the information, so that we can achieve a higher information transmission rate.

根据调制后的信号产生对应位置的脉冲,作为信息的载体通过天线发射出去。 The pulse modulated signal is generated corresponding to the position, as a carrier of information by the antenna out. 脉冲发生器的功能如图11所示。 The pulse generator 11 is shown in FIG.

输入的每一个上升沿通过脉冲发射器都会产生一个可控宽度的脉冲。 Each rising edge of the input pulse by the transmitter will have a controllable pulse width. 脉冲发生器的实现方法有很多种,例如图12所示的类似数字电路结构的一种脉冲发生器。 Implementation There are many pulse generator, such as one similar to the digital pulse generator circuit configuration 12 shown in FIG.

Vin从0上升为1,则B点电压较慢的由1下降为0,这样就会在Y点产生一个负向的脉冲,经过一级反相器,得到正向的脉冲,脉冲的宽度由R,C的参数调节,公式如下所示:t=ReqCln(VCCVth)]]>其中Req为M2的等效电阻,Vth为M2管的阈值电压。 Vin rises from 0 to 1, the voltage at point B decreases to 0 by the slower one, so that it will produce a negative pulse at point Y, via an inverter, to obtain a positive pulse, a pulse width adjustment parameters R, C, the formula is as follows: t = ReqCln (VCCVth)]]> where Req is the equivalent resistance of M2, the threshold voltage Vth of M2 is a tube.

Claims (2)

1.基于超宽带无线脉冲方式的射频卡或射频标签,其特征在于,含有模拟前端、数据存储和处理逻辑、超宽带脉冲调制发射器三个部分,其中模拟前端用模拟电路实现,数据存储和处理逻辑用数字电路实现,超宽带脉冲调制发射器用数模混合电路实现,其中:模拟前端部分,包括接收天线、整流滤波电路、电压转换和稳压电路、解调电路、时钟提取电路以及复位信号产生电路,其中:接收天线,接收读卡器发射天线发出的正弦信号,频点一般是为13.65MHz或者315MHz,为50%ASK幅度键控调制,整流滤波电路,输入端与所述接收天线的输出端相连,将交流信号转换成一定幅值的直流信号并输出直流电压,在有电池供电条件下,可去掉该模块,电压转换和稳压电路,采用负反馈式电压转换和稳压电路,其输入端和与所述整流滤波电路的输出端相连,将整流输 1. Based on RF tags or RF card pulsed ultra-wideband wireless manner, wherein the analog front end comprising three parts, data storage and processing logic, ultra-wideband pulse modulator transmitter, wherein the analog front end analog circuit implementation, data storage, and the processing logic implemented by a digital circuit, a pulse modulated transmit ultra-wideband mixed digital-analog circuit implementation used, wherein: the analog front end section includes a receiving antenna, a rectification filter circuit, a voltage converter and regulator circuit, a demodulation circuit, clock extraction circuit and the reset signal generating circuit, wherein: the receiving antennas, the reader transmitting a sinusoidal signal receiving antennas sent, is typically 13.65MHz frequency or 315MHz, amplitude shift keying of 50% ASK modulation, rectifier and filter circuit, an input terminal of the receiving antenna connected to the output, converting an AC signal into a DC signal of constant amplitude and output DC voltage in a battery powered condition, the module can be removed, and the conversion voltage regulator circuit, the negative feedback type voltage converter and regulator circuit, an input terminal and an output terminal of the rectifying and filtering circuit is connected to the rectified output 的直流电平变换到所需的各种直流电压,复位信号产生电路,输入端与所述整流滤波电路的输出端相连,输出电压复位信号,时钟提取电路,采取反相器交叉耦合的时钟提取电路,输出同频全摆幅方波信号,解调电路,采用包络检波电路,该电路的输入端和所述接收天线的输出端相连,输入信号为读卡器向射频卡或射频标签发送的正弦信号,经包络检波输出数据信息;数据存储和处理部分,由MCU,RAM,FLASH和I/O接口等数字逻辑组成,其中:MCU向RAM,FLASH分别发出存取指令并据此存取数据,MCU向I/O接口发出接收发送指令并据此收发数据,所述I/O接口从所述复位信号产生电路接收复位信号,从所述电压转换和稳压电路输入直流电压,用作数字电源,从都要由所述电压转换和稳压电路供电的解调电路和时钟提取电路中分别提取数据和时钟,经过所述I/O接 DC level shift to the various DC voltages needed, the reset signal generating circuit, an input terminal connected to the output of the rectifier filter circuit, the output voltage of the reset signal, a clock extraction circuit, take the cross-coupled inverters clock extraction circuit , full-swing output frequency with a square wave signal, a demodulation circuit, using envelope detection circuit, connected to the input of the receiving circuit and the antenna output terminal, the input signal is transmitted to the RF card reader or a radio frequency tag a sinusoidal signal, the envelope detection output data; data storage and processing section by the MCU, RAM, FLASH, and I / O interfaces, digital logic, where: MCU issuing an access command to the RAM, FLASH, respectively, and accordingly access data, the MCU receives the transmission sent data to send and receive commands and accordingly I / O interface, the I / O interface generating circuit receives a reset signal from the reset signal from the voltage conversion circuit and the DC input voltage regulator, as digital power, to be extracted by the demodulating circuit and the clock of the voltage regulator circuit and the power conversion circuit and extracts the data clock, respectively, through the I / O contact 进入MCU,经读取存储信息并运算后发出应答信息;超宽带脉冲调制发射器部分,也由所述电压转换和稳压电路供电,且包括依次串接的与数据存储和处理部分数据接口、信道编码器、脉冲调制发生器和发射天线,在所述脉冲调制发生器中采用脉冲位置调制,根据输入信息产生对应位置的脉冲,作为信息载体通过发射天线发射出去。 Into the MCU, a response message sent by the operator and read information stored; ultra-wideband pulse modulator transmitter portion, but also by the voltage regulator circuit and the power converter, and comprises sequentially connected with the data storage and data interface processing section, a channel encoder, a pulse generator and transmitting antenna modulation, pulse position modulation in the modulation pulse generator, in accordance with the input information to generate a pulse corresponding to the position, as an information carrier is radiated through the transmitting antenna.
2.根据权利要求1所述的基于超宽带无线脉冲方式的高速射频卡或射频标签,其特征在于,所述模拟前端接收读卡器通过低频(13.65MHz)或高频(315MHz)正弦波发送的数据和电荷能量,模拟前端通过整流滤波和电压转换和稳压过程模块提供整个电路的电源,并通过解调电路将接收到的信号恢复为读卡器发出的数据,超宽带脉冲调制发射器将待发射的数据经过编码后,通过脉冲产生和调制过程,产生携带信息的符合超宽带定义的脉冲信号,由天线发射。 The pulse-based ultra-wideband wireless high-speed radio card or radio tag according to claim 1, wherein said analog front-end receiving transmitted by the reader low frequency (13.65 MHz) or high frequency (315MHz) sine wave data and energy charge, the analog front end provides power to the entire circuit by rectifying and filtering the voltage conversion and regulation process module, and the received signal to recover data sent to the card reader by the demodulation circuit, ultra-wideband pulse modulator transmitter data to be transmitted after encoding, and generating a pulse modulation process, ultra wideband pulse signal is generated in line with the definition of carrying information transmitted by the antenna.
CN 200610165249 2006-12-15 2006-12-15 Radio-frequency card or radio frequency label based on super wideband wireless pulse mode CN100428263C (en)

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CN101425148B (en) * 2007-10-30 2011-04-20 美国博通公司 Multi-mode rfid tag and its operation method
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US9154264B2 (en) 2011-03-30 2015-10-06 Intel Corporation Device, system and method of wireless communication between circuits
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CN104516381B (en) * 2013-09-26 2016-04-27 上海华虹集成电路有限责任公司 Regulator rectifier circuit in radio-frequency (RF) identification
CN104516381A (en) * 2013-09-26 2015-04-15 上海华虹集成电路有限责任公司 Rectification and voltage stabilization circuit for radio frequency identification
CN104515616B (en) * 2013-09-30 2017-10-17 江苏省电力公司常州供电公司 Transforming plant primary equipment temperature monitoring cruising inspection system
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CN107566007A (en) * 2016-07-01 2018-01-09 拉碧斯半导体株式会社 Chromacoder, processing unit, communication system and signal conversion method

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