Progress on ten-meter optical receiver telescope

Abstract

A ten-meter hexagonally segmented Cassegrain optical telescope is being considered at the Jet Propulsion Laboratory for use as a research and development facility for optical communications technology. The goal of the study is to demonstrate technology which can eventually be used to develop a network of such telescopes to continuously track and communicate with the spacecraft. Hence, the technology has to be economical enough to allow replication for a ground or space based network. As we need to collect signal photons only, the telescope cost can be substantially reduced by accepting lower image quality. An important design consideration for the telescope is its ability to look very close to the sun. The telescope for optical communications must function during the daytime. Indeed, for some planetary missions it may be necessary that the system be capable of looking within a few degrees of the sun. To enable this, a unique sunshade consisting of hexagonal tubes in precise alignment with the mirror segments has been proposed which will also serve as the support for the secondary. Recent progress on the design and analysis of such an optical reception station is discussed here. O-8194-0781-X1921$4.OO SPIE Vol. 1635 Free-Space Laser Communication Technologies IV(1992) / 109 Downloaded From: http://proceedings.spiedigitallibrary.org/ on 06/25/2016 Terms of Use: http://spiedigitallibrary.org/ss/TermsOfUse.aspx [3] Mast, T., Nelson, J., and Welch, W, ' The effects of primary mirror segmentation on telescope image quality, ' Keck Observatory report no. 68, Oct.

<title>Optical networks for earth-space communications and their performance</title>

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“…Ziel, Australia 1.5 133 E 23 S 10 n.a./dry [4] [1] ISCCP satellite data [2] The NOAO 8-M Telescopes proposal to NSF; [3] Preexisting facilities and infrastructure; [4] Information on infrastructure and facilities not available.…”

“…The study of optical subnets draws upon previous design studies of the Deep Space Optical Reception Antenna [3] (DSORA) and work on a weather model [4,5] for ground based laser communications. The study also makes use of work accomplished by TRW, one of the contractors working on the DSRSS Swdy, for the user terminal design concept [6].…”