在信号处理中，它通常是可取的是能够执行某种降噪图像或信号。中值滤波是一种非线性数字滤波技术，通常用于去除噪声。这种噪声是一个典型的前处理步骤，提高后处理的结果（例如，边缘检测在图像）。中值滤波是非常广泛的应用在数字图像处理中，在一定的条件下，它保留了边缘，去除噪声-In signal processing, it is often desirable to be able to perform some kind of noise reduction on an image or signal.

energy detection is the most common type of spectrum sensing because it is easy to implement and requires no prior knowledge about the primary signal

energy detection is the most common type of spectrum sensing because it is easy to implement and requires no prior knowledge about the primary signal