A wideband spectrum analyzer includes at least one signal input, and at least one signal channel with a first filter module and a second filter module. The first filter module and the second filter module are connected with the at least one signal input downstream of the at least one signal input in a series connection. The first filter module includes first switches, and several different highpass filters being arranged in a parallel connection. The first switches are configured to selectively connect one of the highpass filters with an input of the first filter module and an output of the first filter module. The second filter module includes second switches, and several different lowpass filters being arranged in a parallel connection. The second switches are configured to selectively connect one of the lowpass filters with an input of the second filter module and an output of the second filter module.