We report a novel battery-less wireless current sensor node without an analog to digital converter (ADC). If a capacitor is charged using a current transformer (CT) and a rectifying circuit, the charging time depends ...We report a novel battery-less wireless current sensor node without an analog to digital converter (ADC). If a capacitor is charged using a current transformer (CT) and a rectifying circuit, the charging time depends on the current flowing through a power line. In the case that the node transmits data every time when voltage of the capacitor exceeds a threshold voltage, we can indirectly measure the current by measuring the transmission intervals. In this method, the circuit of the node can be simplified and power consumption for the wireless transmission can be decreased because the measured current data does not need to be included in the transmitted packet. However, the measurable range is about single digit because the transmission interval decreases suddenly as the current increases. In this work, we have ex- panded the range using one CT, one wireless transmission module, and two charging circuits that include different load resistors connected in series. The results indicated that the measurable range was from 0.5 A to 50 A.展开更多
Energy source and circuit cost are two critical challenges for the future development of the Internet of Things(IoT).Backscatter communications offer a potential solution to conveniently obtain power and reduce cost f...Energy source and circuit cost are two critical challenges for the future development of the Internet of Things(IoT).Backscatter communications offer a potential solution to conveniently obtain power and reduce cost for sensors in IoT,and researchers are paying close attention to the technology.Backscatter technology originated from the Second World War and has been widely applied in the logistics domain.Recently,both the academic and industrial worlds are proposing a series of new types of backscatter technologies for communications and IoT.In this paper,we review the history of both IoT and backscatter,describe the new types of backscatter,demonstrate their applications,and discuss the open challenges.展开更多
文摘We report a novel battery-less wireless current sensor node without an analog to digital converter (ADC). If a capacitor is charged using a current transformer (CT) and a rectifying circuit, the charging time depends on the current flowing through a power line. In the case that the node transmits data every time when voltage of the capacitor exceeds a threshold voltage, we can indirectly measure the current by measuring the transmission intervals. In this method, the circuit of the node can be simplified and power consumption for the wireless transmission can be decreased because the measured current data does not need to be included in the transmitted packet. However, the measurable range is about single digit because the transmission interval decreases suddenly as the current increases. In this work, we have ex- panded the range using one CT, one wireless transmission module, and two charging circuits that include different load resistors connected in series. The results indicated that the measurable range was from 0.5 A to 50 A.
基金This study was supported in part by the Fundamental Research Funds for the Central Universities(No.2020YJS044)in part by the National Natural Science Foundation of China(Nos.61871026 and U1834210).
文摘Energy source and circuit cost are two critical challenges for the future development of the Internet of Things(IoT).Backscatter communications offer a potential solution to conveniently obtain power and reduce cost for sensors in IoT,and researchers are paying close attention to the technology.Backscatter technology originated from the Second World War and has been widely applied in the logistics domain.Recently,both the academic and industrial worlds are proposing a series of new types of backscatter technologies for communications and IoT.In this paper,we review the history of both IoT and backscatter,describe the new types of backscatter,demonstrate their applications,and discuss the open challenges.
