Coherent optical receiver capable of receiving a multiple-wavelength optical signal (S Multi-λ) composed at least of a succession of single-band optical bursts, each single-band optical burst being carried by a distinct wavelength out of a plurality of carrier wavelengths (λ 1, λ 2, λ 3, λ 4, λ 5) over a determined spectral band, the optical receiver comprising: optical generation means arranged to deliver a single multiple-wavelength optical local oscillator composed of a plurality of optical lines with wavelengths (λ' 1, λ' 2, λ' 3, λ' 4, λ' 5) corresponding to the carrier wavelengths; optical mixing means arranged to receive two optical signals as input, the first of said optical signals being the single multiple-wavelength optical local oscillator and the second of said optical signals being the multiple-wavelength optical signal (S Multi-λ), in order to deliver at least one optical signal (S MIX), called mixed optical signal, composed of a plurality of beats between each of the single-band optical bursts of the multiple-wavelength optical signal (S Multi-λ) and the optical lines of the single multiple-wavelength optical local oscillator; and detection means comprising a photo-electric conversion module followed by at least one electrical module processing the mixed optical signal after conversion in the photo-electric conversion module, in particular an analogue-digital conversion module and/or a digital processing module; the passband (ΔB) of the detection means corresponding to the passband of the electrical module and having a spectral width greater than half the width of the spectral band of said at least one single-band optical burst, so as to filter, from the mixed optical signal, at least one beat between each of the single-band optical bursts and one of the optical lines of the multiple-wavelength optical local oscillator, by allowing passage, for each single-band optical burst, of only the beat between said single-band optical burst and the optical line of wavelength (λ' 3) corresponding to the wavelength (λ 3) carrying said single-band optical burst, while rejecting the beats between said single-band optical burst and the other optical lines of a wavelength not corresponding to the wavelength (λ 3) carrying said single-band optical burst. optical generation means arranged to deliver a single multiple-wavelength optical local oscillator composed of a plurality of optical lines with wavelengths (λ' 1, λ' 2, λ' 3, λ' 4, λ' 5) corresponding to the carrier wavelengths; optical mixing means arranged to receive two optical signals as input, the first of said optical signals being the single multiple-wavelength optical local oscillator and the second of said optical signals being the multiple-wavelength optical signal (S Multi-λ), in order to deliver at least one optical signal (S MIX), called mixed optical signal, composed of a plurality of beats between each of the single-band optical bursts of the multiple-wavelength optical signal (S Multi-λ) and the optical lines of the single multiple-wavelength optical local oscillator; and detection means comprising a photo-electric conversion module followed by at least one electrical module processing the mixed optical signal after conversion in the photo-electric conversion module, in particular an analogue-digital conversion module and/or a digital processing module; the passband (ΔB) of the detection means corresponding to the passband of the electrical module and having a spectral width greater than half the width of the spectral band of said at least one single-band optical burst, so as to filter, from the mixed optical signal, at least one beat between each of the single-band optical bursts and one of the optical lines of the multiple-wavelength optical local oscillator, by allowing passage, for each single-band optical burst, of only the beat between said single-band optical burst and the optical line of wavelength (λ' 3) corresponding to the wavelength (λ 3) carrying said single-band optical burst, while rejecting the beats between said single-band optical burst and the other optical lines of a wavelength not corresponding to the wavelength (λ 3) carrying said single-band optical burst.