Plenary Session I
(10:00-10:20 Coffee Break)
Laser and Sensing Technologies for Space
Lunar Laser Communication Demonstration
Plenary Session III
(Coffee service provided.)
Quantum Technology for Space
Plenary Session II
- Opening Session
- Opening address
Fumihiko Tomita, Vice President, NICT, Japan
- Welcome address
Toshio Kosuge, General Chairperson, ICSOS 2014 Organizing Committee
Professor Emeritus, University of Electro-Communications, Japan
- Guest speech
Tatsuhiro Hisatsune, Director, Space Communications Policy Division, Global ICT Strategy Bureau, Ministry of Internal Affairs and Communications (MIC), Japan
- Plenary Session I
- Yoshihisa Takayama
- [Invited] International Interoperability Standards Development for Space Optical Communication
- John Rush (NASA, USA); Bernard Edwards (NASA Goddard Space Flight Center, USA)
- NASA and other international space agencies are currently developing optical communication systems for spacecraft applications. These applications include both links between spacecraft and links between spacecraft and ground. Six of the agencies formed the Optical Link Study Group (OLSG), under the Interagency Operations Advisory Group (IOAG), to determine if there is a business case for cross support of each other's spacecraft optical communication links. The OLSG recently completed its work and reported that there is a strong business case for cross support of spacecraft optical links. It further concluded that in order to enable cross support the links must be standardized.
This paper will overview the findings and rationale developed by the OLSG in arriving at their conclusion. It will also overview the history and structure of the international standards body, the Consultative Committee for Space Data Systems (CCSDS), that will develop the standards.
The paper will also describe the set of standards that will be developed and outline some of the issues that must be addressed in the next few years as the standards are developed.
(10:00-10:20 Coffee Break)
- [Invited] Overview of the Lunar Laser Communication Demonstration
- Don Boroson (MIT Lincoln Laboratory, USA)
- For one month in late 2013, NASA's Lunar Laser Communication Demonstration (LLCD) successfully demonstrated for the first time duplex laser communications between a satellite in lunar orbit, the Lunar Atmosphere and Dust Environment Explorer (LADEE), and ground stations on the Earth. It constituted the longest-range laser communication link ever built and demonstrated the highest communication data rates ever achieved to or from the Moon. The system included the development of a novel space terminal, a novel ground terminal, two major upgrades of existing ground terminals, and a capable and flexible ground operations infrastructure. This presentation will give an overview of the system architecture and the several terminals, basic operations of the system, and a brief discussion of the results.
- [Invited] European Data Relay System - One Year to Go!
- Harald Hauschildt (ESA, The Netherlands); Francois Garat (ESA, The Netherlands); Heli Greus (ESA, The Netherlands); Khalil Kably (ESA, The Netherlands); Jean-Pascal Lejault (ESA, The Netherlands); Hermann Ludwig Moeller (ESA, The Netherlands); Andrew Murrell (ESA, The Netherlands); Josep Maria Perdigues Armengol (ESA, The Netherlands); Michael Witting (ESA, The Netherlands); Bas Theelen (Airbus Defense and Space, Germany); Matthias Wiegand (Airbus Defense and Space, Germany); Akos Hegyi (Airbus Defense and Space, Germany)
- The service provided by the European Data Relay System (EDRS) is planned to start after in-orbit commissioning of its first node EDRS-A, to be launched in the first quarter of 2015. The programme, run in a Public-Private-Partnership between ESA and Airbus Defense and Space (formerly Astrium Services) (Germany), consists of two geostationary nodes (EDRS-A and EDRS-C) which will provide data relay services via a laser-optical link as well as in Ka-Band. The first customer for the optical service, based on the Laser Communication Terminal manufactured by TESAT Spacecom, is the Copernicus (formerly GMES) Sentinel constellation.
This paper will provide an overview of the EDRS status and its future plans, less than one year from the launch of its first node.
- [Invited] EFAL: EDRS Feeder Link from Antarctic Latitudes - Preliminary Results of Site Investigations, Availability, and System Requirements
- Dirk Giggenbach (DLR, Germany); Ricardo Barrios (DLR, Germany); Florian Moll (DLR, Germany); Ramon Mata Calvo (DLR, Germany); Sergei Bobrovskyi (DLR, Germany); Felix Huber (DLR, Germany); Nighat Johnson-Amin (IPF, Germany); Frank Heine (Tesat Spacecom, Germany); Mark Gregory (Tesat Spacecom, Germany)
- Laser communications from ground to geostationary satellites can enable high-rate data repatriation from remote ground station sites. When employing Arctic or Antarctic ground hubs, the low link elevations impose a major challenge due to the strong atmospheric index-of-refraction turbulence impact and increased attenuation. The usability of the European Data Relays System (EDRS) for data uplinks from an Antarctic ground station has been analyzed in terms of cloud-availability and feasibility in terms of atmospheric turbulence. For model-verification, an on-site wavefront measurement campaign has been carried out. This scenario also serves as worst test-case for future optical GEO-feeder links.
- Lunar Laser Communication Demonstration
- Keith Wilson (JPL, USA)
- Results from a Lunar Laser Communication Experiment between NASA's LADEE Satellite and ESA's Optical Ground Station
- Zoran Sodnik (ESA, The Netherlands); Hans Smit (ESA, The Netherlands); Marc Sans (ESA, The Netherlands); Igor Zayer (ESA, Germany); Marco Lanucara (ESA, Germany); Klaus-Juergen Schulz (ESA, Germany); Dirk Giggenbach (DLR, Germany); Peter Becker (DLR, Germany); Ramon Mata Calvo (DLR, Germany); Christian Fuchs (DLR, Germany); Johannes Widmer (RUAG Space, RUAG Schweiz AG, Switzerland); Felix Arnold (RUAG Space, RUAG Schweiz AG, Switzerland); Martin Mosberger (RUAG Space, RUAG Schweiz AG, Switzerland); Angel Alonso (IAC, Spain); Iciar Montilla (IAC, Spain)
- ESA's optical ground station (OGS) participated in the Lunar Laser Communication Demonstration (LLCD) with the Laser Communication Space Terminal (LLST) onboard NASA's Lunar Atmosphere and Dust Environmental Explorer (LADEE) satellite. The experiment demonstrated the capabilities of optical communication and of inter-agency cross-support for optical communication links. The OGS experimental campaign, which started on October 26 and lasted until November 20, consisted of four days of bidirectional link sessions followed by three days of no operation. Each individual link session lasted approximately 20 minutes and was repeated after two hours. Despite non optimal weather conditions multiple link sessions were performed. The paper describes the design of the transmit laser and data generation system as well as the receiver system. A special chapter is dedicated to lessons learned from transmitter/ receiver alignment problems, which prevented the demonstration of data uplink and ranging from the OGS. Several possibilities to solve the alignment problem are discussed and the finally implemented solution is described.
- Receiver Performance of ESA Ground Terminal During Lunar Laser Communication Demonstration (LLCD)
- Martin Mosberger (RUAG Space, RUAG Schweiz AG, Switzerland); Johannes Widmer (RUAG Space, RUAG Schweiz AG, Switzerland); Felix Arnold (RUAG Space, RUAG Schweiz AG, Switzerland); Fabio Gambarara (RUAG Space, RUAG Schweiz AG, Switzerland)
- NASA's Lunar Laser Communication Demonstration (LLCD) has proved the capabilities of optical communication between the LADEE space craft orbiting the Moon and three complementary ground stations (NASA/MIT, JPL and ESA) on Earth. For ESA's optical ground station on Tenerife, an innovative fibre coupled receiver unit has been developed. It comprises highly sensitive optical detectors, synchronization electronics (for clock recovery and frame synchronisation), a fast decoder (able to decode data at the same speed as it is received) and a large data buffer with a high speed data interface. For modulation and coding, Pulse Position Modulation (PPM) in combination with the Serially Concatenated PPM (SC-PPM) error correction scheme is used.
This paper focuses on the experiment's results and field experience. At ESA's optical ground station, the optical downlink beam at a wavelength of 1550nm was received with a 1m telescope and coupled into a multi-mode fibre. Via this fibre, the receiver unit has successfully detected and decoded a vast amount of data from the LLCD experiment during different passages and at different times of the day. The performance results are analysed and presented. Atmospheric conditions and the fibre coupled approach are discussed and lessons learned are presented. The experiment provides valuable input for both, the further advancement of deep space laser communication as well as for the discussion of optical links through the atmosphere. Both topics have been pursued by RUAG for years.
- Realtime Atmospheric Decision Aids in Support of the Lunar Laser Communications Demonstration
- Randall Alliss (Northrop Grumman Corporation, USA); Billy Felton (Northrop Grumman Corporation, USA)
- Atmospherics, in particular clouds, are a key driver in the performance of free space optical communication (FSOC) systems. Clouds are composed of liquid water and/or ice crystals, and depending on the physical thickness, can produce atmospheric fades easily exceeding 10 decibels (dB).
In these more common cases, impacts on FSOC systems may be severe. On the other hand, there are times when cloud fades may be as low as 1 or 2 dB as a result of thin, ice crystal based cirrus clouds. In these cases, the impacts on FSOC communication collectors may be limited.
The ability to characterize the distribution and frequency of clouds is critical in order to understand and predict atmospheric impacts on FSOC. A realtime cloud analysis and forecasting system has been developed to support the Lunar Laser Communications Demonstration (LLCD). LLCD will demonstrate high data rate optical communications from lunar orbit to three ground sites. The realtime cloud analysis and forecasting system supporting LLCD is composed of remotely sensed clouds derived from geostationary meteorological satellites from the United States Geostationary Operational Environmental Satellite (GOES) and the Meteosat Second Generation (MSG) Severi instrument. Cloud analyses are derived from these satellites for three ground sites: White Sands Complex (WSC), New Mexico, the primary ground site for LLCD; Table Mountain Facility (TMF) in Southern California; and Tenerife Optical Ground Station (OGS) in the Canary Islands. Analyses are derived every 15 minutes at 1-kilometer horizontal resolution. Using these cloud analyses, a Cloud Free Line of Sight (CFLOS) indicator is computed from each site to the current moon position and provided in realtime to mission planners. In addition to the current CFLOS, a short term cloud forecast is derived based on recent motion of clouds around each site. These forecasts are being used for planning purposes to decide which site is most desirable for optical communications during LLCD's next pass around the moon. In addition, a cloud forecast out to 16 days is being used for longer term mission planning. These forecasts are derived from numerical weather prediction models of the atmosphere.
The goal of this capability is to determine the feasibility of using realtime atmospheric products for the mitigation of the effects of clouds on FSOC. The LLCD project gives us the opportunity to quantitatively assess how such products perform so that future space to ground applications, including handover between ground sites, may take advantage of the experience gained. This presentation will show results from the analysis of the forecasting system generated during LLCD.
- Terrestrial Free-Space Optical Communications Network Testbed: INNOVA
- Morio Toyoshima (NICT, Japan); Yasushi Munemasa (NICT, Japan); Hideki Takenaka (NICT, Japan); Yoshihisa Takayama (NICT, Japan); Yoshisada Koyama (NICT, Japan); Hiroo Kunimori (NICT, Japan); Toshihiro Kubo-oka (NICT, Japan); Kenji Suzuki (NICT, Japan); Shinichi Yamamoto (NICT, Japan); Shinichi Taira (NICT, Japan); Hiroyuki Tsuji (NICT, Japan); Isao Nakazawa (NICT, Japan); Maki Akioka (NICT, Japan)
- It is rather important to research on the influence of terrestrial weather conditions for free-space laser communications. The site diversity is one of the solutions, where several ground stations are used. The National Institute of Information and Communications Technology (NICT) is developing a terrestrial free-space optical communications network for future airborne and satellite-based optical communications testbed called IN-orbit and Networked Optical Ground Stations Experimental Verification Advanced Testbed (INNOVA). Several optical ground stations and environmental monitoring stations around Japan will be presented.
- Poster Session
- Lunar Optical Communications Link (LOCL): Measurements of Received Power Fluctuations and Wavefront Quality
- Dirk Giggenbach (DLR, Germany); Peter Becker (DLR, Germany); Ramon Mata Calvo (DLR, Germany); Christian Fuchs (DLR, Germany); Zoran Sodnik (ESA, The Netherlands); Igor Zayer (ESA, Germany)
- During the laser communication link experiments between NASA's LADEE and ESA's optical ground station on Tenerife island, DLR-IKN carried out received-power measurements using a highly sensitive power detector, and wavefront quality analysis using the focal speckle pattern method.
This paper reports on the evaluation of power fluctuation statistics and wave-front quality under varying elevations, times of day, and lunar background light.
- High-Bit-Rate Laser Space Communication Technology and Results of On-Board Experiment
- Vladimir Kovalev (OJC "RPC "PSI", Russia); Victor Sumerin (OJC "RPC "PSI", Russia); Vladimir Grigoryev (OJC "RPC "PSI", Russia); Victor Shargorodskiy (OJC "RPC "PSI", Russia)
- This paper is devoted to laser data transfer experiment between ISS and on-ground terminal performed by "RPC PSI" and RKK "Energia". The description of used hardware, and experimental results are listed.
- Synchronous Tests of Laser Active ARTEMIS Satellite at Different Ground Stations
- Volodymyr Kuzkov (Main Astronomical Observatory of National Academy of Sciences, Ukraine); Sergii Kuzkov (Main Astronomical Observatory of National Academy of Sciences, Ukraine); Vincenzo Caramia (Redu Space Services S.A., ESA, Redu Station, Belgium); Alexander Shulga (Mykolaiv Astronomical Observatory, Ukraine); Vladimir Rikhal'sky (National Space Devices Control and Test Centre of State Space Agency of Ukraine, Ukraine); Yevgen Kozyryev (Mykolaiv Astronomical Observatory, Ukraine); Yevgeniya Sybiryakova (Mykolaiv Astronomical Observatory, Ukraine); Vladimir Lopachenko (National Space Devices Control and Test Centre of State Space Agency of Ukraine, Ukraine); Alexander Kozhukhov (National Space Devices Control and Test Centre of State Space Agency of Ukraine, Ukraine)
- In July 2001, the geostationary satellite ARTEMIS with laser communication terminal OPALE on board was launched. Successful laser communication sessions were performed between ARTEMIS and low Earth orbiting (LEO) satellite SPOT-4. Regular laser communication experiments between the Optical Ground Station (OGS) of ESA and ARTEMIS were also performed. The laser communication sessions were successfully established between LEO satellite KIRARI and ARTEMIS. A laser communication link between LEO satellites with the data rate of 5.625 Gbps (5100 km distance) was established by the TESAT Spacecom in 2008. First laser communication experiments between the LADEE spacecraft at the lunar orbit and Earth OGS with a rate of 622 Mbps were realized in October 2013.
The amount of information sent from telecommunication satellites located at the geostationary orbit is constantly increasing. There is a certain demand in high speed laser link data transmission between ground stations and satellites. For some LEO satellites, the direct transmission of information to a ground station is required. To reduce the influence of atmosphere, some of ground stations located in different climatic regions are needed. The Main Astronomical Observatory of Ukraine (MAO) have developed a compact laser communication system named LACES (Laser Atmospheric and Communicational Experiments with Satellites) using the Cassegrain focus of its 0.7 m telescope. The laser link between the LACES terminal of MAO and the OPALE terminal of ARTEMIS was established. During the pointing, OPALE terminal performs the beacon laser scanning of the territory where a MAO ground station is located. Several experimental observations of OPALE beacon laser scanning by ground stations located in different regions of Ukraine took place in 2012-2013 years. During the sessions, laser beacon peaks from OPALE were detected by the stations in Kyiv, Mykolaiv (500 km from Kyiv), Yevpatoriya (800 km from Kyiv), Odesa, and other stations. Selected results of the experiments are presented in the report.
- Evaluation of Inertial Stabilization System
- Masaki Haruna (Mitsubishi Electric Corporation, Japan); Kazuhide Kodeki (Mitsubishi Electric Corporation, Japan); Seiichi Shimizu (Mitsubishi Electric Corporation, Japan); Kazuhiko Fukushima (Mitsubishi Electric Corporation, Japan); Osamu Takahara (Mitsubishi Electric Corporation, Japan); Toshiyuki Ando (Mitsubishi Electric Corporation, Japan); Jiro Suzuki (Mitsubishi Electric Corporation, Japan); Eisuke Haraguchi (Mitsubishi, Japan)
- For an observation satellite that requires high pointing stability, the issue is that the micro vibrations generated from some internal disturbance sources such as a reaction wheel degrade the image resolution. To suppress the pointing error of an optical telescope, some systems have been developed e.g., a passive isolation system and an inertial stabilization system.
In general, the inertial stabilization system can suppress the pointing error from a lower frequency to a high frequency than a passive isolation system because the inertial stabilization system includes active control. Therefore, our research focuses on the inertial stabilization system. The system requires precise drive, less than 0.3urad, wide control bandwidth, over 100Hz, and tolerance for launch load.
A prototype mechanism and control equipment are designed based on concepts that it has non-contact actuators and sensors, and flexural pivots are applied to support a stabilized platform in order to meet two requirements which are precise drive and tolerance for launch load. Two kind of inertial sensors are installed on the platform to measure the wideband attitude. Each of these two inertial sensors covers each band signal and these signals are combined as one wideband signal to stabilize the platform in inertial space.
In this paper, the developed prototype mechanism and control equipment are described and the basic evaluation results are reported. The development of the system has not completely finished yet, but the basic performance is certified to meet the requirement. From now on, we continue to develop the system. These future results can be applied to inter-satellite laser communication system.
- Development of Fine Pointing Mechanism for Optical Inter-Satellite Communication
- Seiichi Shimizu (Mitsubishi Electric Corporation, Japan); Kazuhiko Fukushima (Mitsubishi Electric Corporation, Japan); Kazuhide Kodeki (Mitsubishi Electric Corporation, Japan); Toshiyuki Ando (Mitsubishi Electric Corporation, Japan); Tomohiro Araki (JAXA, Japan)
- Laser-based optical inter-satellite communication equipment enables large capacity communication, which is essential for future observation satellites that handle huge amounts of data. One of the key technologies for optical inter-satellite communication equipment is the rapid, highly accurate acquisition and tracking of the corresponding satellite. Therefore, Mitsubishi Electric Corporation and JAXA are developing the fine pointing mechanism for an optical inter-satellite communication. The fine pointing mechanism is designed on the assumption of equipped in the geostationary satellite, and the design life of the fine pointing mechanism is 15 years. This paper describes the specifications, mechanism, control system and performance evaluation results of the fine pointing mechanism.
- Dual Wavelength Optical Coherent Receiver Front End for Inter-Satellite Communication
- Toshiyuki Ando (Mitsubishi Electric Corporation, Japan); Eisuke Haraguchi (Mitsubishi, Japan); Takashi Sugihara (Mitsubishi Electric Corporation, Japan); Jiro Suzuki (Mitsubishi Electric Corporation, Japan); Kazuhide Kodeki (Mitsubishi Electric Corporation, Japan); Tomohiro Araki (JAXA, Japan)
- This paper presents the new concept of 1.06um/1.55um dual wavelength optical coherent receiver frontend which can obtain optical phase error signals in PSK communication data as well as spatial tracking error without any extra tracking sensor, leading to downsizing of optical intersatellite communication terminals. This new receiver frontend consists an optical 90 deg hybrid mixer with free space optical components, segmental photo detectors and RF electronics, to realize not only balanced detection of both in-phase and quadrature components but also heterodyne detection of tip/ tilt error signals.
- High-Performance Multichannel Superconducting Single-Photon Detector System with Compact Cryocooler
- Taro Yamashita (NICT, Japan); Shigehito Miki (NICT, Japan); Hirotaka Terai (NICT, Japan); Zhen Wang (Shanghai Institute of Microsystem and Information Technology, China)
- We present high-performance multichannel superconducting nanowire single-photon detector system with a compact Gifford-McMahon (GM) cryocooler. The best device showed a system detection efficiency (SDE) of 74%, dark count rate (DCR) of 100 cps, and full width at half maximum timing jitter of 68 ps at a bias current of 18.0 μA. SDEs of 6 detectors mounted on the cryocooler were shown to be higher than 67% at the DCR of 100 cps.
- High-Frame Rate Wavefront Sensor Based on Flexible Read-Out Technique for C-MOS Image Sensor
- Jiro Suzuki (Mitsubishi Electric Corporation, Japan); Toshiyuki Ando (Mitsubishi Electric Corporation, Japan); Eisuke Haraguchi (Mitsubishi, Japan); Takao Endo (Mitsubishi Electric Corporation, Japan); Yoshichika Miwa (Mitsubishi Electric Corporation, Japan)
- In this paper, high frame-rate Shack Hartmann wavefront sensor with a C-MOS image sensor is presented. To realize high data rate wavefront sensor we adopted the flexible read out technique on C-MOS sensor, which makes it possible to reduce not only the amount of Hartmann spot but also image size. In the preliminary experiments, we have successfully obtained 10x10-Hartmann diagram with a rate of 4 kHz, leading to a high frame-rate wavefront sensor.
- Application of Compact Optical Duplicate System as a Multi-Beam Generation Device for Satellite-Ground Laser Communications
- Tomoko Nakayama (Tokai University, Japan); Yoshihisa Takayama (NICT, Japan); Chiemi Fujikawa (Tokai University, Japan); Eriko Watanabe (The University of Electro-Communications, Japan); Kashiko Kodate (Japan Women's University, Japan)
- Satellite-ground laser communication has been of particular interest because of increase in the quantity of data exchanged between satellites and the ground. It is necessary to improve the quality of data communication, because laser communication is vulnerable to air fluctuation. This paper reports on a simulation conducted to reduce the efficiency loss due to air fluctuations. The simulation used data from a beam transmission experiment in the atmosphere. We propose an optical duplicate system for a multi-beam generation device for satellite–ground laser communications. This is a device that generates many reproduction images for optical computing and optical information processing, the validity of which has been proven and is widely known. This device enables more efficient miniaturization and weight saving than previous techniques, and it is flexible in terms of the number of optical beams. We designed the optical duplicate system for satellite–ground laser communications, and proved the validity of this system by simulations.
- In-Orbit and Networked Optical Ground Stations Experimental Verification Advanced Testbed (INNOVA): The High-Performance and Compact Ground-Tracking System
- Toshiaki Yamashita (NEC Corporation, Japan); Motoaki Shimizu (NEC Corporation, Japan); So Nishimura (NEC Corporation, Japan); Toshihiro Nishizawa (NEC Corporation, Japan); Masatoshi Nakai (NEC Corporation, Japan); Yasushi Munemasa (NICT, Japan); Yoshisada Koyama (NICT, Japan); Yoshihisa Takayama (NICT, Japan); Morio Toyoshima (NICT, Japan)
- The high-performance and compact groundtracking system has been developed for the terrestrial free-space optical communication network facility called in-orbit and networked optical ground stations experimental verification advanced testbed "INNOVA". It consists of the "dual" 2-axis gimbals, the fine pointing mechanism (FPM), the optical widerange acquisition sensor (WAS), the optical coarse acquisition sensor (CAS), the optical tracking sensor (FPS), the wavefront correction sensor (WCS) and the deformable mirror for the adaptive-optics (AO) function, and the high-performance controller. The FPM, WAS, CAS, FPS, and AO function are unified as the optical module, and its beam-direction is directly controlled by the 2-axis gimbals. A CMOS image-sensor base of InGaAs is commonly applied to WAS, CAS, FPS, and WCS; the acquisition ranges for WAS and CAS are each tuned by the telescope magnification, and the accuracy of CAS and FPS is determined by the focus distance. In the optical module, the beam-direction is aligned to the optical-fiber by FPM based on the measurement signal of WAS, CAS, and FPS. The "dual" 2-axis gimbals have the mechanism of the coarse and fine axes for each azimuth and elevation axis. The corporation control between the gimbals and FPM is achieved using the synchronized WAS, CAS, FPS, and WCS signals. Then, 40Gbps digital coherent optical transponder / 10Gbps IMDD optical transponder can be chosen for the free-space optical communication on the system.
- Environmental Data Gathering System for Satellite-to-Ground Station Optical Communications
- Kenji Suzuki (NICT, Japan); Toshihiro Kubo-oka (NICT, Japan); Tetsuharu Fuse (NICT, Japan); Shinichi Yamamoto (NICT, Japan); Hiroo Kunimori (NICT, Japan); Morio Toyoshima (NICT, Japan)
- In the optical space communication between satellite-ground stations, if site diversity is constructed among two or more ground stations connected with the terrestrial network, it will be thought that the link can be established with certainty in one of ground stations. But by storing the data based on weather survey data quantitatively and statistically, and carrying out analysis processing needs to show the validity. Therefore, in this paper show the environmental-data collection system that collects data from sensors installed at approximately 10 appropriate locations throughout Japan.
- Modeling of Atmospheric Turbulence Effects on the Laser Beam Propagation by Exponential Distribution
- Mohsen Firoozmand (Imam Hussein University, Iran); Mohammad Reza Mahozun (Imam Hussein University, Iran); Mohammad Reza Hedayati Rad (Imam Hussein University, Iran)
- Free Space Optical communication (FSO) developed in last decade. Wide bandwidth and high security is two characteristics of FSO link. But, atmospheric channel is effective upon these systems. Cognition of channel is very important for electro_optic system design, suitable utilization and propagation analysis. Three phenomena of atmospheric, that are effective upon Laser Beam, are: Absorption, Scattering and Turbulence. In this paper will be investigated, turbulence and turbulence effects in FSO links. Turbulence atmospher Occurs due continual and random changing of refractive index. Atmospheric turbulence result is laser beam deviation and phase deviation. Turbulence effects in FSO links is like fading in electromagnetic wireless communication. Here it is assumed that channel is composed of atmospheric masses. Every of the masses has special Dimension and refractive index. Strong, Medium and Weak Turbulence are three types of turbulence state. The refractive index structure parameter is Criterion for turbulence state. The first step in this paper is estimation of dimension of masses based on refractive index structure parameter. Probability density function that used in this stage is Exponential function. For calculation of masses dimension, by exponential function, λ is determined based on . Also Refractive index changes of atmospheric masses is estimated by the exponential probability density function. Again, λ, in exponential function calculated based on . In the next step, by these functions is calculated beam deviation and phase deviation in receiver side. By using this method is estimated atmospheric masses dimensions and their refractive index. In the last step, SNR and BER is calculated for a FSO link (with receiver optimal aperture size).
- Suggestion of Geometric Correction to Measurement of Fried's Parameter by DIMM
- Tomohiro Watanabe (Tokyo Metropolitan University, Japan); Yoshihisa Takayama (NICT, Japan); Hajime Fukuchi (Tokyo Metropolitan University, Japan)
- In this paper, effect of atmospheric turbulence and the measurement method of Fried's parameter γ0 that is needed to evaluate the turbulence are summarized. We tried the measurement of Fried's Parameter using DIMM (Differential Image Motion Monitor) method. But the influence of extension of the image by having used a prism is seen in the measurement result. So we propose geometric correction and inspect its validity of the correction.
- Measurements of the Refractive Index Structure Constant and Studies on Beam Wander
- Keiichi Yano (Shibaura Institute of Technology, Japan); Yoshihisa Takayama (NICT, Japan); Koichi Gyoda (Shibaura Institute of Technology, Japan)
- A setup of a simplified optical ground station is studied for receiving laser stably in the space optical communications. We study the reception system that takes into account the beam wander that is a matter of peculiar atmospheric propagation.
- Study on Coding Parameters for a Small Optical Transponder
- Hideki Takenaka (NICT, Japan); Yoshihisa Takayama (NICT, Japan); Yoshisada Koyama (NICT, Japan); Yasushi Munemasa (NICT, Japan); Eiji Okamoto (Nagoya Institute of Technology, Japan); Maki Akioka (NICT, Japan); Morio Toyoshima (NICT, Japan)
- We recently developed a small optical transponder (SOTA) for a 50-kg-class satellite. The SOTA is equipped with modules for processing error-correcting codes. In this paper, we present the results of a study on the parameters of error correcting codes by experimenting with ground-to-satellite laser communication links. In order to do this, a SOTA simulator (SOTA-SIM) was designed. We demonstrate optical communication between buildings using low-density generator matrix (LDGM) code at distance of 7.8 km. The demonstration was to study how the coding parameters, code rate, and interleaving depth affect the quality.
- Comparative Study on Low-Rate Forward Error Correction Codes in Downlink Satellite-to-Ground Laser Communications
- Hiroaki Inoue (Nagoya Institute of Technology, Japan); Eiji Okamoto (Nagoya Institute of Technology, Japan); Yozo Shoji (NICT, Japan); Yoshihisa Takayama (NICT, Japan); Morio Toyoshima (NICT, Japan)
- In high-speed satellite-to-ground laser communications, it has been shown that the Markov-based erasure channel model is well suited for the downlink experiment results. In that model, since the average erasure rate is relatively high, a low-rate error correction code is needed. In this paper, we focus on the application of low rate systematic Luby transform (SLT) code and show that the performance of SLT code is better than low-density generator matrix (LDGM) code in the downlink satellite-to-ground laser channel when using a short interleaver.
- High Reliable Optical Satellite Communications Using an Network Coding
- Yoshikuni Miyata (Mitsubishi Electric Corporation, Japan); Kenya Sugihara (Mitsubishi Electric Corporation, Japan); Wataru Matsumoto (Mitsubishi Electric Corporation, Japan); Toshiyuki Ando (Mitsubishi Electric Corporation, Japan)
- One of the problem for optical satellite communications is how to avoid shading between a ground station and a satellite. For this problem, we propose a new scheme using an network coding for the next generation optical satellite communications. At the satellite as the transceiver, parity packets are generated from information packets using the network coding encoder. The information and parity packets are transmitted to some optical paths, via some data-relay satellite, and are received at the some ground stations. These information and parity packets are collected at the data center via a ground network. And finally these received packets are used for regeneration the original information based on the decoding scheme of the network coding. We also propose the scheme that we can change each coding rate of the network coding to adjust to the space optical channel environment. By using these scheme, we can transmit information data from a satellite efficiently even if shading or degradation of a space optical channel is occurred.
- A Study on Layer 1 Network with Low Power Consumption for Data Relay Satellite
- Yuta Takemoto (Mitsubishi Electric Corporation Information Technology R&D Center, Japan); Yoshiaki Konishi (Mitsubishi Electric Corporation, Japan); Takashi Sugihara (Mitsubishi Electric Corporation, Japan); Tomohiro Araki (JAXA, Japan)
- We study the optical data relay satellite system on layer 1 network with low power consumption for data relay satellite, that focus on FEC function. The data relay satellite system is that LEO satellite and ground station communicate with each other via the data relay satellite. In this paper, we propose the system configuration that the data relay satellite has no FEC decoder. We compare the BER performance of the data relay satellite with FEC decoder and without FEC decoder. We use the Reed-Solomon encoder and decoder in this study. As a result, we show almost the same BER between the data relay satellite with FEC decoder and without decoder that the section between the data relay satellite and ground station is under the BER of 1.0 × 10-3.
- Joint Detection and Tracking of Satellite via Bernoulli Filtering
- Baishen Wei (The University of Western Australia, Australia); Brett Nener (The University of Western Australia, Australia)
- In general, a satellite can randomly enters or exit the field of view of the sensor. Moreover, even when the satellite is within the field of view, mis-detections can occur. In addition, the sensor also receives spurious detection or false alarming due to the large population of space debris. Standard dynamic state estimation techniques are not adequate to cope with this scenario. This paper presents a method for joint detection and tracking of satellite in the presence of mis-detection or false alarming.
- Optically Controlled Beam Former Using Phased Array Laser
- Eisuke Haraguchi (Mitsubishi Electric Corporation, Japan); Junya Nishioka (Mitsubishi Electric Corporation, Japan); Jiro Suzuki (Mitsubishi Electric Corporation, Japan); Toshiyuki Ando (Mitsubishi Electric Corporation, Japan)
- Optically controlled beam forming techniques are promising candidate to realize a large scale phased array antenna system. In this paper, we study the optical phase locking of multiple optical beams to apply optically beam former for receiving phased array antenna. We demonstrated in the bench top experiment of three beams system, each optical signal phase has been stabilized with relative phase error less than 0.2 degrees.
- Dependable Optically Differential Reconfigurable Gate Array
- Masato Seo (Shizuoka University, Japan); Minoru Watanabe (Shizuoka University, Japan)
- Currently, demand for highly-dependable field programmable gate arrays (FPGAs) is increasing for space systems. However, current SRAM-based FPGAs are vulnerable to high-energy charged particles. Therefore, recently, one type of optical FPGA, optically-reconfigurable gate arrays (ORGAs), have been developed. The reconfiguration of ORGAs is extremely robust because it uses holographic memory technology. However, its robust configuration capability can be increased even further if the number of bright bits or binary state Highs can be decreased by modifying the configuration context pattern, Therefore, this paper presents a dependable optically differential reconfigurable gate array (ODRGA). The experimental results clarify the high configuration reliability of this dependable ODRGA.
- Sodium Lidar Laser/Telescope Alignment Technique Applied to Satellite-Earth Optical Communications
- Takuya Kawahara (Shinshu University, Japan); Yoshichika Imai (Shinshu University, Japan); Yoshihisa Takayama (NICT, Japan)
- The angle between emitted laser and a telescope line of sight is discussed for the case of a sodium lidar. The alignment method has been quite empirical so far but we have developed a quantitative and simple alignment technique that uses backscattered laser light from atmosphere below 20 km altitude. In the case of the Na lidar, by using the technique, the angle between the laser and the telescope line of sight is assured to be less than 0.25 mrad. Applying this technique to beacon laser alignment of laser satellite communication systems, the angle of the laser and the telescope line of sight can be expected less than 0.1 mrad (satellite orbit; 600 km, telescope/laser distance on the ground; 1 m).
- Matching and Co-Registration of Satellite Images Using Local Features
- Mohamed Tahoun (Suez Canal University - Faculty of Computers and Informatics, Egypt); Abd El Rahman Shabayek (Suez Canal University - Faculty of Computers and Informatics, Egypt); Aboul Ella Hassanien (University of Cairo, Egypt)
- Satellite image matching and co-registration are two key stages in image registration, fusion and super-resolution imaging processes where images are taken from different sensors, viewpoints or at different times. This paper presents: (1) An evaluation for the co-registration process using local feature detectors, (2) A registration scheme for registering optical images taken from different viewpoints, in addition to radar images taken at different times. The selected feature detectors (SURF, SIFT, ORB and BRISK) have been tested during the key point extraction, descriptor construction and matching processes. The framework suggests a sub-sampling process which controls the number of extracted key points for a real time processing and for minimizing the hardware requirements. After getting the pairwise matches between the two images, a registered image is composited by applying bundle adjustment and image warping enhancements. The results showed a good performance for SURF over both SIFT and ORB detectors in terms of higher number of inliers, repeatability ratios and robustness to noise. The Experiments were done on different optical and radar images from Rapid-Eye, Terra SAR-X, and ASTER satellite data for some areas in Germany and Egypt.
- Future Prospect on Space Communication Infrastructure for Remote Sensing Satellites
- Akira Iwasaki (University of Tokyo, Japan); Takeo Tadono (Japan Aerospace Exploration Agency, Japan)
- Since earth observation satellites contribute in many fields of our life, such as disaster monitoring, environmental surveillance and weather forecast, the requirements on observation data are increasing to be higher in frequency as well as spatial and spectral resolution. Therefore, the amounts of data provided by on-board sensors become too large to downlink to ground stations. Nowadays, space communication is one of the bottle-neck for earth remote sensing satellite system. In this work, future prospect on space communication system using new technologies, such as intersatellite link and optical communication, is addressed based on the analysis of future Japanese remote sensing satellites. The future communication system that provides a large amount of data is also effective to deliver the observation data to any ground station in the world.
- Plenary Session II
- Zoran Sodnik (ESA, The Netherlands)
- [Invited] Impact of Pointing Performance on the Optical Downlink for the Optical PAyload for Lasercomm Science (OPALS) System
- Bogdan Oaida (Jet Propulsion Laboratory/California Institute of Technology, USA); Michael Kokorowski (Jet Propulsion Laboratory/California Institute of Technology, USA); Baris Erkmen (Google, Inc, USA); Kenneth Andrews (Jet Propulsion Laboratory, USA); William Wu (Quantitative Engineering Design™, Inc., USA); Marcus Wilkerson (Jet Propulsion Laboratory/California Institute of Technology, USA)
- The Optical PAyload for Lasercomm Science (OPALS), developed at JPL, is a technology demonstration project which is set to begin operations from the International Space Station in early 2014. Its goal is to demonstrate the feasibility of an optical communication link from low-Earth orbit (LEO), i.e. the ISS, to a ground terminal located at JPL's Optical Communications Telescope Laboratory (OCTL). Pointing performance is a key consideration, and often a driver, in the design of space-to-ground optical communications links, as was the case for our project. In this paper we discuss how the allocations for the pointing system were derived and the impact of the pointing performance on the optical downlink. We address the contributions from static and quasi-static pointing offsets (bias) as well as those from the fast-dynamic disturbances produced by the two-axis gimbal and control loop (jitter). Results from laboratory testing are presented and compared to the requirements.
- [Invited] The Approach to Realize a Higher Speed, More Compact and Longer-Lasting Operational Optical Space Communications System
- Tomohiro Araki (JAXA, Japan); Kazuya Inaoka (JAXA, Japan); Yoshiyuki Tashima (JAXA, Japan); Satoshi Ichikawa (JAXA, Japan); Masanobu Yajima (JAXA, Japan)
- The requirements of optical space communication technology mean smaller onboard communication terminals must be developed and operated to satisfy future data transmission needs in the 2020s and beyond. JAXA has developed the "KIRARI OICETS" (Optical Inter-orbit Communication Engineering Test Satellite) and established acquisition, pointing and tracking techniques on orbit. The optical communication terminal "LUCE" on "KIRARI" is large (150 kg) and has a low data rate (50 Mbps) compared to the practical requirement imposed, hence our wish to achieve a more high speed, compact and long-lasting optical communication terminal. We describe our recent activity to achieve a new-generation optical communication terminal by applying excellent ground optical communication technologies and new devices.
- Lasercom From Mars: Orbiters, Landers, and CubeSats
- Hamid Hemmati (Jet Propulsion Laboratory (JPL), USA); Abhijit Biswas (Jet Propulsion Laboratory (JPL), USA)
- Numerous successful near-Earth laser communications (lasercom) link demonstrations have been made. The next challenge is to demonstrate deep-space links from asteroids, comets, and planets to Earth. In this paper we describe recent concepts for communications from spacecraft visiting planet Mars. Communications links, including trunk line from Mars orbiting spacecraft, and from small lasercom terminals on Mars landed assets or onboard interplanetary CubeSats to Mars are discussed. Uplink communications with some of these flight terminals are also described. Substantial gains are shown over conventional telecommunications, given equivalent mass and power consumption at the spacecraft, and typically one tenth the aperture diameter.
- German Roadmap on Optical Communication in Space
- Bjorn Guetlich (DLR, Germany); Rolf Meyer (DLR, Germany); Sabine Philipp-May (DLR, Germany); Michael Lutzer (DLR, Germany); Ines Richter (DLR, Germany); Anke Pagels-Kerp (DLR, Germany); Markus Bibus (DLR, Germany)
- Germany identifies optical communication as a strategic space-technology. Past and present in-orbit achievements and future goals on the German Roadmap towards optical communication in space are discussed. Inter-satellite and Ground link results are covered.
- Atmospheric Turbulence
- Morio Toyoshima
- Recent Developments in Adaptive Optics for the LCRD Optical Ground Station at Table Mountain
- Keith Wilson (JPL, USA); Lewis Roberts (NASA Jet Propulsion Laboratory, USA)
- The NASA Laser Communications Relay Demonstration project plans to launch an optical payload onboard a satellite destined for a geostationary slot between 60 degrees and 161degrees West latitude. The payload consists of two optical heads with control electronics that relay data between two ground terminals. Current plans call for demonstrating the relay link between ground terminals in Hawaii and the JPL Table Mountain Optical Communications Telescope Laboratory (OCTL) in California. The data formats for the links are pulse position modulation (PPM) and differential phase shift keying (DPSK) at maximum data rates of 311 Mbps and 1.24Gbps DPSK, respectively. The coherent DPSK optical links require implementing Adaptive Optics (AO) to correct wave front aberrations, and enable efficient coupling of the downlink signal into the single-mode receiver fiber. The AO system at OCTL is required to provide wave front correction at 20 degrees elevation, with corresponding Fried coherence parameters of 5.2cm measured at zenith and 500 nm wavelength.
- Experimental Analysis of Channel Coherence Time and Fading Behavior in the LEO-Ground Link
- Florian Moll (DLR, Germany)
- Characterization and modeling of the optical communication channel in the LEO-ground scenario are a matter of ongoing research. Especially, knowledge about the temporal behavior of the channel is of big importance because it allows development and optimization of channel codes and interleavers to overcome the problem of power fluctuations and thus, signal loss. In this paper, the channel coherence time and fading statistics seen by a 40 cm aperture on ground are experimentally investigated and a modeling approach is given and discussed.
- Characterization of Atmospheric Turbulence for LEO to Ground Laser Beam Propagation at Low Elevation Angles
- Nicolas Vedrenne (ONERA, France); Marie-Therese Velluet (ONERA, France); Vincent Michau (ONERA, France); Géraldine Artaud (CNES, France); Frederic Lacoste (CNES, France); Etienne Samain (OCA-Géoazur, France); Clément Courde (OCA-Géoazur, France)
- Data transfer from Low Earth Orbit satellites to ground implies the availability of communication link at various elevations. Increasing the overall downlink capacity implies communication even at low elevation angle. Optical laser link throughput capacities are highly dependent on propagation conditions. Unfortunately these conditions are more severe at low elevations due to a longer path in the turbulent atmosphere. Dedicated mitigation strategies have to be developed to address propagation channel impairments. But the choice of the technique and its efficiency depends on our knowledge of the perturbations. In the small perturbations regime analytical formalism has been developed to describe the statistical properties of the perturbations. However, at low elevation angles, analytical formalism can no longer be exploited. In the saturation regime heuristic approaches have been proposed. However, wave optics models are the most powerful tool to estimate the impact of atmospheric turbulence whatever the pertubations. Nervertheless, different questions have to be answered to develop such a code: spatial sampling of phase screens, longitudinal sampling of the turbulence profile along the line of sight …Whereas propagation conditions are well documented for elevation angles above 30°, few measurements have been made and published for elevations below. The present paper reports experimental measurements of turbulence characteristics, both in nighttime and daytime. They were recorded in the visible spectrum using stars as sources. Elevation angles down to 10° were addressed. These measurements were performed with a fast Shack-Hartmann wavefront sensor, installed at the Coudé focus of the MeO laser telescope at Observatoire de la Cote d'Azur during summer 2013. Atmospheric turbulence characteristics (spatial and temporal spectra of scintillation and phase) are estimated from the measurements and compared to wave optics results.
- Laser Experiments with ARTEMIS Satellite in Cloudy Conditions
- Volodymyr Kuzkov (Main Astronomical Observatory of National Academy of Sciences, Ukraine); Sergii Kuzkov (Main Astronomical Observatory of National Academy of Sciences, Ukraine); Zoran Sodnik (ESA, The Netherlands); Vincenzo Caramia (Redu Space Services S.A., ESA, Redu Station, Belgium)
- In July 2001, the ARTEMIS satellite with laser communication terminal OPALE on board was launched. 1789 laser communications sessions were performed between ARTEMIS and SPOT-4 (PASTEL) from 01 April 2003 to 09 January 2008 with total duration of 378 hours. In addition ESA's Optical Ground Station (OGS) performed laser communication experiments with OPALE in various atmospheric conditions.
Since the launch of ARTEMIS, the amount of information handled by geostationary telecommunication satellites has increased dramatically and so has the demand for data rate that needs to be transmitted from ground. With limited bandwidth allocations in the radio frequency bands interest has grown for laser communication feeder link technology. In this respect there is interest to compare the influence of atmosphere conditions in different atmospheric regions with respect to laser transmission. Two locations are being compared, namely ESA's OGS (located in an altitude of 2400 m above sea level) and the Main Astronomical Observatory of Ukraine (MAO) (located at an altitude of 190 m above sea level).
In 2002 MAO started the development of a ground laser communication system for the AZT-2 telescope. The MAO developed compact laser communication system is called LACES (Laser Atmosphere and Communication Experiments with Satellites)  and the work was supported by the National Space Agency of Ukraine and by ESA. The beacon laser from OPALE was occasionally detected even in cloudy conditions and an anomalous atmospheric refraction at low elevation angles was observed. The main results of laser experiments with ARTEMIS through clouds are presented in the paper.
- Laser and Sensing Technologies for Space
- Hiroo Kunimori
- [Invited] Development of 2-Micron Doppler Wind Lidar for NASA 3-D Winds Mission
- Upendra Singh (NASA Langley Research Center, USA); Michael Kavaya (NASA Langley Research Center, USA); Mulugeta Petros (NASA Langley Research Center, USA); Jirong Yu (NASA Langley Research Center, USA)
- We review the 20-plus years of pulsed transmit laser development at NASA Langley Research Center (LaRC) to enable a coherent Doppler wind lidar to measure global winds from earth orbit. We briefly also discuss the many other ingredients needed to prepare for this space mission.
- The Overview of JAXA Laser Energy Transmission R&D Activities and the Orbital Experiments Concept on ISS-JEM
- Daisuke Goto (JAXA, Japan); Hiroyuki Yoshida (JAXA, Japan); Hiroaki Suzuki (JAXA, Japan); Katsuto Kisara (JAXA, Japan); Kazuo Ohashi (JAXA, Japan); Yoshinori Arimoto (NICT, Japan)
- The SSPS (Space Solar Power System) is a potential energy supply infrastructure which uses laser or microwave to transmit energy from spacecraft to the ground facilities. The Laser SSPS (L-SSPS) has the following advantages: (1) smaller spacecraft designs and (2) smaller ground facilities, as well as the following disadvantages: (3) significantly affected by the atmospheric disturbance and weather and (4) eye safety issues. JAXA has continued R&D programs of laser energy transmission to help resolve the technological difficulties of L-SSPS. The first step of the L-SSPS demonstration is the 500m horizontal laser energy transmission experiments, which were conducted in 2013 and technological data were obtained. The second step will be the 100-200m vertical laser energy transmission experiments, which will be conducted in 2015. The orbital laser energy transmission experiments, from the ISS (International Space Station) –JEM (Japanese Experiment Module, Kibo) to the ground, are expected to constitute the third step.
- Plenary Session III
- Upendra Singh (NASA Langley Research Center, USA)
- [Invited] A Space Based Optical Communications Relay Architecture to Support Future NASA Science and Exploration Missions
- Bernard Edwards (NASA Goddard Space Flight Center, USA); David Israel (NASA Goddard Space Flight Center, USA); Donald Whiteman (NASA Goddard Space Flight Center, USA)
- Space optical communications, onboard data processing, and Delay Tolerant Networking (DTN) are key communication technologies in development at the National Aeronautics and Space Administration (NASA) for possible deployment on future space based relays. The Laser Communications Relay Demonstration (LCRD) project, scheduled for launch in March 2018 as a hosted payload on a commercial communications satellite, is a critical pathfinder towards NASA providing optical communications services on the Next Generation Tracking and Data Relay Satellite. The project builds upon the success of the recent Lunar Laser Communication Demonstration (LLCD) and leverages the technologies developed for it. This paper provides an update on both projects and on other Near-Earth space optical communication developments at NASA, and describes a possible optical communications architecture for future Geosynchronous Earth Orbit (GEO) relays to support multiple science and exploration missions. This paper will also touch on the necessary commercialization of optical communications and the development of inter-operability standards.
- Preparative Demonstration of Optical Link Establishment by Using Small Optical Transponder
- Yoshihisa Takayama (NICT, Japan); Yoshisada Koyama (NICT, Japan); Hideki Takenaka (NICT, Japan); Yasushi Munemasa (NICT, Japan); Maki Akioka (NICT, Japan); Morio Toyoshima (NICT, Japan)
- Preparative demonstrations of optical link establishment conducted by using the small optical transponder are introduced. The first demonstration employs the engineering model to connect the distance about 8km. The second demonstration is carried out by the proto-flight model in the distance about 1.2km to measure the tracking accuracy under the influence of atmosphere. The third one is performed to observe the effect of an error correction coding, where an optical terminal that is almost the copy of the proto-flight model is used as the simulator. Through those demonstrations, the designed specifications are confirmed.
- Laser Communication Terminal: Product Status and Industrialization Process
- Herwig Zech (TESAT Spacecom, Germany); Frank Heine (TESAT Spacecom, Germany); Matthias Motzigemba (TESAT Spacecom & Company, Germany)
- Laser Communication Terminals have left the status of R&D programs and are now applied in commercial satellite communication systems. The European Data Relay System (EDRS) is based on optical intersatellite links at a data rate of 1.8 Gbps for its commercial data relay service. In this paper, the key design elements of the Laser Communication Terminal (LCT) applied for EDRS are presented and the most important performance parameters are given. An overview of the status of the current LCT programs will be presented. The next steps involve the further industrialization of the LCT. Targets are streamlining the integration flow, stabilizing the supply chain and to seek for design modifications within the qualification boundary conditions based on available LCT AIT experiences. The modular LCT design ensures that the heritage derived from the EDRS LCT can be transferred to other applications for the laser communication terminals. The modular design allows to spin off parts of the LCT as standalone products to further broaden the range of applications. The status of this industrialization process is given.
- Functional System Verification of the OPTEL-μ Laser Downlink System for Small Satellites in LEO
- Thomas Dreischer (RUAG Space, RUAG Schweiz AG, Switzerland); Björn Thieme (RUAG Space, RUAG Schweiz AG, Switzerland); Klaus Buchheim (RUAG Space, RUAG Schweiz AG, Switzerland)
- In 2010, RUAG Space has started with support from ESA the development of a complete system called OPTEL-μ for direct to ground laser downlinks from LEO satellites. It provides up to 2 Gbit/s information data rate and follows the request for the three elementary features small-ness, robustness and versatility. The emphasis lies on a compact and robust terminal that mainly addresses the needs of the emerging market of micro satellites to increase data download capabilities at comparable on-board resource constraints .
- OSIRIS Payload for DLR's BiROS Satellite
- Christopher Schmidt (DLR, Germany); Martin Brechtelsbauer (DLR, Germany); Fabian Rein (DLR, Germany); Christian Fuchs (DLR, Germany)
- Direct optical communication links might offer a solution for the increasing demand of transmission capacity in satellite missions. Although direct space-to-ground links suffer from limited availability due to cloud coverage, the achievable data rates can be higher by orders of magnitude compared to traditional RF communication systems.
DLR's Institute for Communication and Navigation is currently developing an experimental communication payload for DLR's BiROS satellite. The OSIRIS payload consists of a tracking sensor for a precise alignment between satellite and groundstation, an optical uplink channel, two different and independent laser sources and an optical bench with the transmission optics.
This paper will give an overview about the BiROS satellite, the OSIRIS payload and the performance of the system, including space-qualification of the hardware and transmission tests.
- Quantum Technology for Space
- Hamid Hemmati (Jet Propulsion Laboratory (JPL), USA)
- Toward High Capacity and Secure Global Quantum Communication
- Masahide Sasaki (NICT, Japan); Te Sun Han (NICT, Japan); Hiroyuki Endo (Waseda University & NICT, Japan)
- Quantum info-communication technologies directly control the quantum mechanical properties of photons. Then one can go beyond the capabilities of conventional technologies. For example, quantum communication can achieve the ultimate channel capacity of optical link maximizing the rate in bits/s/Hz/photon.
Quantum cryptography can ensure unbreakable secure communications even by any future technologies. These two have been studied separately so far. Recently, however, one has started to see a new merged scheme, where both efficient transmission and provable security can be realized simultaneously, reaching the secrecy capacity as the maximum rate in secure bits/s/Hz/photon. We present the latest results on this new scheme, especially on theory and implementation in space.
- Quantum Teleportation Over a 143km Free-Space Link
- Thomas Herbst (Austrian Academy of Sciences, Austria); Thomas Scheidl (Austrian Academy of Sciences, Austria); Daqing Wang (Austrian Academy of Sciences, Austria); William Naylor (Austrian Academy of Sciences, Austria); Bernhard Wittmann (Austrian Academy of Sciences, Austria); Rupert Ursin (Austrian Academy of Sciences, Austria); Anton Zeilinger (Institute for Quantum Optics and Quantum Information, Austria); Xiao-Song Ma (Yale University, USA); Johannes Kofler (Max-Planck-Gesellschaft, Germany); Elena Anisimova (University of Waterloo, Canada); Vadim Makarov (University of Waterloo, Canada); Thomas Jennewein (University of Waterloo, Canada)
- Quantum teleportation  is a quintessential prerequisite of many quantum information-processing protocols. By using quantum teleportation, one can circumvent the nocloning theorem  and faithfully transfer unknown quantum states. It can also be used to create entanglement between formally completely independent particles via the process of entanglement swapping , which will be of utmost importance in a future quantum-communication network , since it enables the global interconnection of quantum computers. We employed a 143 km optical free-space link between the two Canary Islands La Palma and Tenerife and successfully showed quantum teleportation under real world conditions. In particular the average state fidelity for the teleported quantum states was more than 6 standard deviations beyond the classical limit of 2/3 and the process fidelity was 0.710(42). Our work proofs the feasibility of ground-based free-space quantum teleportation. This experiment represents a crucial step towards future quantum networks in space. The technology implemented in our experiment reached the required maturity both for satellite and for long-distance ground communication.
- Characterization of 64 Pixel NbTiN Superconducting Nanowire Single Photon Detectors
- Shigehito Miki (NICT, Japan); Taro Yamashita (NICT, Japan); Zhen Wang (Shanghai Institute of Microsystem and Information Technology, China); Hirotaka Terai (NICT, Japan)
- We present the characterization of two-dimensionally arranged 64-pixel NbTiN superconducting nanowire single-photon detector (SSPD) array. NbTiN films deposited on thermally oxidized Si substrates enabled the high-yield production of high-quality SSPD pixels, and all 64 SSPD pixels showed uniform superconducting characteristics within the small range of 7.19–7.23 K of superconducting transition temperature and 15.8–17.8 μA of superconducting switching current. Furthermore, all of the pixels showed single-photon sensitivity, and 60 of the 64 pixels showed a pulse generation probability after photon absorption higher than 90%.
- High Altitude Demonstration of Correlated Photon Source for Satellite-Based Quantum Key Distribution
- Zhongkan Tang (Centre for Quantum Technologies, Singapore); Rakhitha Chandrasekara (Centre for Quantum Technologies, Singapore); Yong Sean Yau (Centre for Quantum Technologies, Singapore); Cliff Cheng (Centre for Quantum Technologies, Singapore); Christoph Wildfeuer (Kantonsschule Sursee, Switzerland); Alexander Ling (National University of Singapore, Singapore)
- We report the design and implementation of a small and power efficient system for producing and monitoring high quality correlated photon pairs. The system is implemented in a ruggedized package and is brought to 35.5km above sea level by a weather balloon to test its robustness. This compact and rugged photon pair system is suitable for deployment on low resource platforms such as remote nodes of a quantum key distribution network hosted on nanosatellites.
- Closing address
Hiroyuki Yano, Vice Chairperson, ICSOS 2014 Organizing Committee
Director General, Wireless Network Research Institute, NICT, Japan