Abstract: A multi-aperture free-space optical communications receiver comprises a plurality of telescopes each having a clear objective aperture with a diameter between 50 mm and 250 mm and arranged for receiving light collectively from an optical communications light source. A coherent combiner unit is configured for coherently combining the collectively received light to produce a combined optical signal therewith. Each telescope is arranged in association with, respectively, a wavefront detector to determine a wavefront of said received light directed to it by the respective telescope, a steerable reflector unit including a deformable mirror controllable to deform according to said determined wavefront such that said received light is reflected by the deformable mirror with a modified wavefront, and an optical signal receiver comprising a single-mode optical fibre.

Abstract: A multi-aperture free-space optical communications receiver comprises a plurality of telescopes each having a clear objective aperture with a diameter between 50 mm and 250 mm and arranged for receiving light collectively from an optical communications light source. A coherent combiner unit is configured for coherently combining the collectively received light to produce a combined optical signal therewith. Each telescope is arranged in association with, respectively, a wavefront detector to determine a wavefront of said received light directed to it by the respective telescope, a steerable reflector unit including a deformable mirror controllable to deform according to said determined wavefront such that said received light is reflected by the deformable mirror with a modified wavefront, and an optical signal receiver comprising a single-mode optical fibre.

Abstract: Communication apparatus comprises a first transceiver unit (205A) and a signal processing device (106) configured to receive a signal from the first transceiver unit and to produce a signal for transmission by the first transceiver unit. A cable (201A) connects the first transceiver unit to the signal processing device. The first transceiver unit comprises a housing; a first pair of transducers (204T, 204R) located at, or adjacent, a first end of the housing, and a second set of transducers (206T, 206R) located at, or adjacent, an opposite end of the housing.

Abstract: Communication apparatus comprises a first transceiver unit (205A) and a signal processing device (106) configured to receive a signal from the first transceiver unit and to produce a signal for transmission by the first transceiver unit. A cable (201A) connects the first transceiver unit to the signal processing device. The first transceiver unit comprises a housing; a first pair of transducers (204T, 204R) located at, or adjacent, a first end of the housing, and a second set of transducers (206T, 206R) located at, or adjacent, an opposite end of the housing.