Direct Sampling Receiver with an Adjustable Bandpass Filter for Use in Passive Radar with FM Radio

This paper presents a direct sampling receiver with an adjustable bandpass filter for passive radar with FM radio. The adjustable bandpass filter allows the advantages of a direct sampling receiver, such as its good linearity properties, to be exploited without the use of additional attenuators at high signal levels, which leads to an increased noise figure, or narrowband filters with a fixed centre frequency, which limits the flexibility in the selection of the useful signal.