This paper introduced a new signal processing method -Compressive Sensing (CS). Recently

an emerging theory of signal acquirement named Compressive Sensing become one of the hottest topics of signal sampling and image processing.It is a novel signal sampling theory under the condition that the signal is sparse or compressible.It has the ability of compressing a signal during the process of sampling.It consists of three main areas:sparse representation matrix

measurement matrix and reconstruction algorithm. This paper mainly introduces the model of Compressive Sensing

and the main reconstruction algorithms

then analyses and compares the algorithms.Finally

the paper lists the main applications of Compressive Sensing.