Adding noise to enhance weak signal is a common sensing phenomenon in animal kingdom, but it is not common in artificial sensor. Now, researchers at Penn State University add a small amount of background noise to enhance very weak signals when the light source is too dark to sense. For most sensors, noise is a problem that should be suppressed. Now researchers have found that adding the right amount of background noise can actually enhance a weak signal to a detectable level. < / P > < p > their sensors are based on a two-dimensional material called molybdenum disulfide, which detects light, but the same principle can also be used to detect other signals. Moreover, compared with traditional sensors, it requires very small energy and space, so it can find wide adaptability in the coming Internet of things (IOT). The Internet of things will deploy tens of millions of sensors to monitor the condition of homes and factories, and low energy requirements will be a strong advantage. Saptarshi DAS, an assistant professor of Engineering Science and mechanics at Pennsylvania State University, said the phenomenon is common in nature. For example, a paddlefish that lives in muddy water can’t actually find its food by sight, a phytoplankton called Daphnia. The paddlefish has an inductive receiver that can receive very weak electrical signals from Daphnia at a distance of 50 meters. If you add a little noise, it can find water fleas at 75 meters or even 100 meters. This ability increases the animal’s evolutionary success. < / P > < p > another interesting example is the gem beetle, which can detect forest fires from a distance of 50 miles. State of the art infrared detectors can only detect from 10 to 20 miles. This is because these animals use a phenomenon called stochastic resonance. Stochastic resonance is a phenomenon in which weak signals below the sensor detection threshold can be detected in the presence of limited and appropriate noise. In their paper, the researchers demonstrated the first use of this technique to detect sub threshold photon signals. One possible use under consideration is for combat forces. Military personnel in the field have carried very heavy equipment. It is not feasible to increase the heavy and power consuming equipment needed to enhance the subthreshold signal. Their technology can also be used in resource constrained environments or under the ocean, where people need to monitor very weak signals. It can also be used in volcanic areas or earthquake monitoring, timely warning. The next step is to demonstrate the technology on silicon photodiodes, which will make the device highly scalable. Any state-of-the-art sensor can be enhanced by this concept. Spontaneous combustion at a Guangzhou Motor vehicle intersection and other traffic lights in Shenzhen