A reflector antenna comprising: a dual-band waveguide feed (210; 810; 910) configured to receive an input signal in a first transmission mode, the input signal including a plurality of frequencies arranged into upper and lower frequency bands, and the waveguide feed including means for converting a transmission mode of the upper frequency band from a first transmission mode to a mixed transmission mode including the first transmission mode and a second transmission mode; a reflector; a splashplate (230; 830) configured to direct a beam emitted from an aperture of the waveguide feed to the reflector; and a splashplate support (240; 840; 940) comprising a first engaging portion (240a; 840a; 940a) for engaging with the waveguide feed, a second engaging portion (240c; 840c, 840c) for engaging with the splashplate, and a supporting portion (240b; 840b; 940b) connecting the first engaging portion to the second engaging portion and arranged to define a space between the waveguide feed aperture and the splashplate, the splashplate support being formed of a dielectric material, wherein the supporting portion has a thickness equal to substantially λ/2, where λ is a characteristic wavelength of the beam inside the supporting portion, wherein the characteristic wavelength λ is a wavelength corresponding to a centre frequency of a transmission band of the beam emitted from the aperture of the waveguide feed, or a mean wavelength of a plurality of wavelengths included in the beam emitted from the aperture of the waveguide feed, or a wavelength having a value between a mean wavelength of a plurality of wavelengths included in the beam emitted from the aperture of the waveguide feed and a wavelength corresponding to a centre frequency of a transmission band of the beam emitted from the aperture of the waveguide feed. a dual-band waveguide feed (210; 810; 910) configured to receive an input signal in a first transmission mode, the input signal including a plurality of frequencies arranged into upper and lower frequency bands, and the waveguide feed including means for converting a transmission mode of the upper frequency band from a first transmission mode to a mixed transmission mode including the first transmission mode and a second transmission mode; a reflector; a splashplate (230; 830) configured to direct a beam emitted from an aperture of the waveguide feed to the reflector; and a splashplate support (240; 840; 940) comprising a first engaging portion (240a; 840a; 940a) for engaging with the waveguide feed, a second engaging portion (240c; 840c, 840c) for engaging with the splashplate, and a supporting portion (240b; 840b; 940b) connecting the first engaging portion to the second engaging portion and arranged to define a space between the waveguide feed aperture and the splashplate, the splashplate support being formed of a dielectric material, wherein the supporting portion has a thickness equal to substantially λ/2, where λ is a characteristic wavelength of the beam inside the supporting portion, wherein the characteristic wavelength λ is a wavelength corresponding to a centre frequency of a transmission band of the beam emitted from the aperture of the waveguide feed, or a mean wavelength of a plurality of wavelengths included in the beam emitted from the aperture of the waveguide feed, or a wavelength having a value between a mean wavelength of a plurality of wavelengths included in the beam emitted from the aperture of the waveguide feed and a wavelength corresponding to a centre frequency of a transmission band of the beam emitted from the aperture of the waveguide feed. a wavelength corresponding to a centre frequency of a transmission band of the beam emitted from the aperture of the waveguide feed, or a mean wavelength of a plurality of wavelengths included in the beam emitted from the aperture of the waveguide feed, or a wavelength having a value between a mean wavelength of a plurality of wavelengths included in the beam emitted from the aperture of the waveguide feed and a wavelength corresponding to a centre frequency of a transmission band of the beam emitted from the aperture of the waveguide feed.