The present invention relates to a multiple access space laser communications optical system. According to the present invention, multiple optical signals containing a number of channels are simultaneously received and demultiplexed at a multiple access communication device. Separate communication signals may be multiplexed by the multiple access communication device, and transmitted through the same or a different telescope optical assembly used to receive communication signals. Double-pass reflection is used to selectively polarize signals and to ensure that signals are substantial normal to optical bandpass filters, to avoid large shifts in the wavelengths transmitted by the optical bandpass filters. The system is capable of providing discrete communications with a number of communication endpoints, regardless of where the communication endpoints are located within the field of view of the telescope optical assembly.

Multiple access space communications optical system using a common telescope aperture

The present invention relates to a numerous user laser communications optical system. Numerous optical signals comprising a number of channels are simultaneously received and demultiplexed (and/or multiplexed and transmitted) at a numerous access communication device. The numerous access communication device may comprise multiple stages that each include a multiple order waveplate and a polarizing beam splitter. The multiple order waveplate is configured so that it retards a first electrical field component of signals corresponding to certain channels in a frequency grid in an integer multiple of wavelengths with respect to a second electrical field component, and retards a first electrical field component of signals corresponding to other channels in the frequency grid in an integer multiple of wavelengths plus one-half a wavelength with respect to a second electrical field component. Separation can then be performed on the basis of the resulting opposite polarization.

I. Gurantz

Papers

Multiple-access communication using coded pulse interval modulation