外文翻译--频率范围.docVIP

英文原文 RFID Frequency Ranges Used Because RFID systems generate and radiate electromagnetic waves, they are legally classified as radio systems. The function of other radio services must under no circumstances be disrupted or impaired by the operation of RFID systems. It is particularly important to ensure that RFID systems do not interfere with nearby radio and television, mobile radio services (police, security services, industry), marine and aeronautical radio services and mobile telephones. The need to exercise care with regard to other radio services significantly restricts the range of suitable operating frequencies available to an RFID system (Figure 1-1). For this reason, it is usually only possible to use frequency ranges that have been reserved specifically for industrial, scientific or medical applications. These are the frequencies classified worldwide as ISM frequency ranges (Industrial–Scientific–Medical), and they can also be used for RFID applications. In addition to ISM frequencies, the entire frequency range below 135 kHz (in North And South America and Japan:400 kHz) is also suitable, because it is possible to work with high magnetic field strengths in this range, particularly when operating inductively coupled RFID systems. The most important frequency ranges for RFID systems are therefore 0–135 kHz,and the ISM frequencies around 6.78 (not yet available in Germany), 13.56 MHz,27.125 MHz, 40.68 MHz, 433.92 MHz, 869.0 MHz, 915.0 MHz (not in Europe),2.45 GHz, 5.8 GHz and 24.125 GHz.An overview of the estimated distribution of RFID transponders at the various frequencies is shown in Figure 1-2. AVAILABLE PRACTICAL RFID FREQUENCIES Figure1-1 The frequency ranges used for RFID systems range. The frequency ranges used for RFID systems range from the myriametric range below 135 kHz, through short wave and ultrashort wave to the microwave range, with the highest frequency being 24 GHz. In the frequency range above 135 kHz the ISM bands available