Abstract: Optical distributed antenna systems comprising a head-end unit adapted to transmit downlink a modulated optical signal with wavelength ?0 and N un-modulated optical signals with wavelength ?N and N remote units (RU) and including at least one circulator. In some embodiments, an HE unit includes an arrangement of a single circulator coupled to a single detector, the arrangement preventing beating. In some embodiments, a RU includes a reflective electro-absorption transceiver (REAT) which includes a single optical interface and a single RF port. The REAT detects the optical signal with ?0 and converts it into a RF signal, and reflects an un-modulated optical signal with wavelength ?N to provide a modulated uplink optical signal. In some embodiments, a RU is configured as an optical antenna unit. In some embodiments, a plurality of RUs is combined with passive optical distribution units to provide hierarchical DAS architectures.

Abstract: Optical distributed antenna systems comprising a head-end unit adapted to transmit downlink a modulated optical signal with wavelength ?0 and N un-modulated optical signals with wavelength ?N and N remote units (RU) and including at least one circulator. In some embodiments, an HE unit includes an arrangement of a single circulator coupled to a single detector, the arrangement preventing beating. In some embodiments, a RU includes a reflective electro-absorption transceiver (REAT) which includes a single optical interface and a single RF port. The REAT detects the optical signal with ?0 and converts it into a RF signal, and reflects an un-modulated optical signal with wavelength ?N to provide a modulated uplink optical signal. In some embodiments, a RU is configured as an optical antenna unit. In some embodiments, a plurality of RUs is combined with passive optical distribution units to provide hierarchical DAS architectures.

Abstract: A method of multiplexing optical signals in a node of an optical network including as inputs a plurality of electrical signals, a plurality of laser transmitters, and as outputs a plurality of optical fibers, (a) generating clock pulses as a first clock frequency; (b) dividing the clock pulses respectively into a number of parallel trigger outputs; (c) sampling the electrical signals respectively by triggering on the parallel trigger outputs; (d) converting the sampled electrical signals to sampled optical signals by modulating respectively the laser transmitters with the sampled electrical signals and outputting respectively the sampled optical signals on the optical fibers; (e) combining the sampled optical signals onto a single optical fiber.