Provided is a wireless signal receiver including: an analog-digital converter (ADC) converting an analog RF signal into a digital baseband signal; and a sub-sampling block dividing and processing the digital baseband signal into a first path signal and a second path signal, and extracting a complex baseband signal by using a relative sample delay difference between the first and second path signals, wherein the first path signal is a signal obtained by adjusting a sample delay and sampling rate of the digital baseband signal, and the second path signal is a signal obtained by filtering without adjusting the sampling rate of the digital baseband signal.