备战天津2023英语高考训练之阅读理解100篇其六

备战天津2023英语高考训练之阅读理解100篇其六 篇51 As smartphone users know,a sleeping device can still consume the power of a battery.One solution for extending the battery life of wireless devices is to add a wake-up receiver that can tun on a shut-off device. Angad Rekhi,a university student,and Amin Arabians,an assistant professor have developed a wake-up receiver that turns on a device in response to ultrasonic （超声波的）signals.By working at a significantly smaller wavelength and switching from radio waves to ultrasound,this receiver is much smaller than similar wake-up receivers. this wake-up receiver has many potential applications,particularly in designing the next generation of networked devices,including the smart devices that can communicate directly with one another without human's role. Once attached to a device,a wake-up receiver listens for a unique ultrasonic pattern that tells it when to turn the device on.It only needs a very small amount of power to maintain this constant listening,so it still saves energy. The designing of these receivers presented a number of challenges. " wake-up receivers and driving down power consumption while maintaining or extending range are fundamental challenges," Angad said. "By doing so,the receivers can be small but powerful enough to fit in with the environment." By comparison,the ultrasound wake-up receiver requires a battery but has much greater range than the wirelessly powered devices.These two technologies-wireless power and wake-up receivers would likely serve different purposes,but both indicate a turning point in devices that make up the Internet of things. "In light of a long-promised future where interconnected,autonomous,widespread and remarkable technologies make life easier,the networked devices available now,like video doorbells and app-enabled lights,seem like rather slight advances." the researchers explained.They believe technologies could help cross the gap between the Internet of things as we know it and the Internet o