Abstract: A signal generation apparatus includes an extraction unit and a conversion unit. The extraction unit is configured to extract part of a frequency waveform as an extracted waveform. The frequency waveform is a waveform represented by a function of frequency. The part of the frequency waveform corresponds to frequencies satisfying a preset extraction condition indicating that amplitude of the frequency waveform is high. The conversion unit is configured to convert the extracted waveform extracted by the extraction unit into a time waveform, which is a waveform represented by a function of time, and generate the time waveform as a signal.

Abstract: A waveguide slot antenna includes a waveguide having a plurality of slots spaced apart by a predefined distance in a central-axis direction of the waveguide, as a radiating section. An uneven section provided on an outer wall surface around the radiating section has a periodic concave-convex pattern extending from the radiating section. The uneven section includes a plurality of protrusions spaced apart by a predefined distance in a dispersed manner in each of an axis direction parallel to the central-axis of the waveguide in which the plurality of slots are arranged and an axis direction orthogonal to the central-axis of the waveguide, and grooves between the protrusions. The plurality of protrusions and the grooves causes incident waves incident from forward in a direction of radiation of radio waves emitted from the radiating section to be reflected in a direction different from an incident direction of the incident waves.