RFID sensor using pulse processing

Patent Granted A radio frequency identification device having sensing elements incorporated in its tags, and the sensing value determines the width of a sensing pulse in its RFID code. Through a pulse-processing unit, during communication, digital sensing values are obtained by measuring the width of the sensing pulse. Since only discrete signals exist, the tag device is insensitive to the fluctuation in its power supply voltage, which is derived from a continuous wave RF carrier. This RFID sensing device can be used broadly in wireless remote sensing, especially in detecting properties inside an object, for example, measuring inner temperature of a human body, measuring a patient's heart and breathing rates inside cloth, or the temperature in a product or shipping container, etc. The inexpensive nature of the RFID sensing tags make them also ideal for applications in massively distributed sensor networks. According to The a latest RFID market research from IDTechEx (www.idtechex.com), in 2012 the value of the entire RFID market was $7.67 billion.