1. Introduction
The theory of compressed sensing (CS) provides a new approach for signal acquisition wherein signal can be exactly reconstructed using a small number of random linear measurements, under certain sparsity conditions [1]. Since most signals are indeed compressible in some transform domains, CS has attracted a lot of attention in many applications, including medical imaging, camera design, and multimedia sensor networks due to its potential of reduction of sampling rates, power consumption and computation complexity in the image acquisition.