Patent ID: 8559556

Claim:
A bandpass sampling method of an analog RF signal receiving system which receives an analog RF signal and converts the analog RF signal into a digital signal by bandpass sampling with a single-sideband signal conversion, comprising: a bandpass filtering step of selecting one or more analog RF signal of a desired frequency band; a converting step of converting the bandpass-filtered signals into complex signals which contain only a single-sideband spectrum by removing either negative or a positive frequency components in a frequency domain; and a bandpass sampling step of bandpass sampling the complex signals with a lower sampling frequency that can down-convert RF bandpass signals to baseband signal, and further configuring the filtered signal obtained in the bandpass filtering step as an I channel signal and configuring the complex signals obtained in the converting step as a Q channel signal to form a complex single sideband signal I(t)+jQ(t) which has only either the positive or the negative frequency components, wherein the signal Q(t) is expressed by the following equation: Q ⁡ ( t ) = I ⁡ ( t ) * 1 π ⁢ ⁢ t where, a symbol * represents a convolution operation, 1/pt represents an impulse response function of a converter applied in the converting step and t represents a time variable.