Numerical evaluation on sub-Nyquist spectrum reconstruction methods

1 Introduction As wireless technology continues to expand,there is a growing concern about the efficient use of spectrum resources.Even though a significant portion of the spectrum is allocated to licensed primary users(PUs),studies indicate that their actual utilization is often limited to between 5％to 10％[1].The underutilization of spectrum has given rise to cognitive radio(CR)technology,which allows secondary users(SUs)to opportunistically access these underused resources[2].However,wideband spectrum sensing,the key of CR,is limited by the need for high-speed analog-to-digital converters(ADCs),which are costly and power-hungry.