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    Reflection on Small Satellite Constellation Operations from the Commercial Space Perspective

    2019-04-05 07:57:12WANGChangqingYUANHongyiZHAOQimingLIUYuxiang
    Aerospace China 2019年4期

    WANG Changqing ,YUAN Hongyi ,ZHAO Qiming ,LIU Yuxiang

    1 China Aerospace Science and Industry Aerodynamics Technology Academy,Beijing 100074 2 Hiwing Satellite Operation Division,China Aerospace Science and Industry Aerodynamics Technology Academy,Beijing 100070

    Abstract:With the advances of small satellite technology in commercial space sector,using small satellite networks to form a satellite constellation and conduct commercial operational services has entered into a vigorous phase of development.As small satellite technology develops,problems in the operations of small satellite constellations are also gradually emerging.These include ground measurement and operational control systems for small satellite constellations,the commercial operational mode,support and the guarantee of laws and regulations related to small satellites.This report discusses the development of commercial space small satellite operation industrialization,explores the small satellite operational modes and technological innovation,proposes the commercial space industry chain to build the industry ecology.At the same time,it looks forward to the integration of space and terrestrial communication.It also calls on relevant organizations of China to speed up the process of space legislation,formulate the relevant policies to encourage the operations of small satellites in commercial space sector,and push China’s commercial space to a new level.

    Key words:commercial space,small satellite,satellite constellation,constellation operating,trend analysis

    1 INTRODUCTION

    With the continuous progress in space technology represented by small satellites,small satellite manufacturing,small satellite commercial launches,small satellite constellation networking and small satellite constellation operation and service have become the most active areas in commercial space.The use of small satellite networks to form satellite constellations,so to implement commercial satellite operational services,has entered the stage of competition.Compared with medium-and high-orbit large satellites,small satellites have many advantages,such as low investment and operational cost,a short system development cycle,high emergency response capability and flexibility,plus a strong data acquisition capability.They are being widely used in the field of communications and remote sensing.Due to the technical characteristics of satellite navigation,small satellites have not been widely used in the field of navigation.At present,small satellites which can be developed standardized,miniaturized,modernized,with low cost and low risk,can be batch produced and promote the construction of multi-platform,multi-function,multi-application and interconnected small satellite constellations,enabling a new pattern of the coexistance of large-and medium-sized satellites plus small satellites,the interconnection of satellites,the networking of satellite constellations and collaborative applications,to make up for the inadequacy of traditional space service.

    Commercial space has injected new impetus into the development of the traditional space industry.Due to the change of the competition and cooperation pattern in various branches of the space industry,as a key factor of the value of commercial space,operation needs to accelerate the transformation from“cost center”to“profit center”.This requires the satellite operation to develop to a scale,specialization,platform and service,and build the satellite operational mode,with competitive advantage and profitability around the three elements of“resources”+“cost”+“value-added services”,so as to provide a new concept for the development of commercial space and satellite applications.

    2 SMALL SATELLITE CONSTELLATION DEVELOPMENT STATUS

    2.1 Development Status of the Global Small Satellite Industry

    Since the 1990s,many developed countries have carried out research and development on small satellites.At present,the United States,France,Great Britain,Germany and so on have gradually deployed small satellite constellation systems.Many developing countries are also actively promoting the development and application of small satellite constellations through independent research and development and seeking international cooperation.

    In 2018,461 types of spacecraft were launched,including 321 small satellites under 500 kg,which accounting for 69.6%of the total annual satellite launches,in which the number of satellites with a mass less than 10 kg was the most.In the field of applications,government departments and commercial organizations are the main users,and technical tests and Earth observation are the fields with the largest number of satellites,accounting for 86% of the total number of small satellites,as shown in Figure 1.Although the number of communications satellites,space science satellites and deep space probes were relatively low,important breakthroughs have been made compared with the previous years.

    Figure 1 Global small satellite application field distribution

    2.2 Development Status of the Small Satellite Industry Abroad

    At present,with the support of considerable commercial funding,space enterprises are developing rapidly.From the perspective of the number of development projects,the number of newly established space enterprises continues to increase.From 2000 to 2017,a total of about 180 new space enterprises from around the world were established with the support of angel investment and venture capital accelerating their development in recent years.From the development perspective,commercial space companies led by SpaceX and OneWeb have become major forces in the world commercial space launch market,laying out the low-orbit small satellite constellation programs,which have entered a stage of rapid development.Starlink LEO communications satellite constellation from SpaceX,plans to launch 42,000 small communications satellites.Starlink satellite internet will realize seamless network management and continuous service,with low cost,short delay,high capacity,high adaptation and so on. OneWeb plans to deploy 900 satellites,achieving seamless global coverage.Planet Labs’“DOVE”remote-sensing satellite constellation is composed of DOVE remote-sensing satellites.It will be the largest constellation of Earth imaging satellites in the world at present,with about 350 satellites in orbit.

    2.3 Development Status of Domestic Small Satellite Industry

    As the commercialization potential for small satellites becomes more and more obvious,China’s small satellites and small satellite manufacturing industry are facing a broad market potential.At present,many small satellite manufacturing companies (China Spacesat,Chang Guang Satellite,Institute of Astrology,Galaxy Space,Spacety Co.,etc.)are keeping pace with each other.Under the backdrop of an expanding space sector with the allocation of market resources,China’s traditional space enterprises,China Aerospace Science and Technology Corportaion (CASC)and China Aerospace Science and Industry Corporation (CASIC)as well as the emerging private commercial aerospace enterprises,are embarking on the construction of communications and remote sensing small satellite constellations.

    As to communications satellites,commercial space projects such as the Hongyun project,Xingyun project,Hongyan project and Yinhe-1 are the main driving force for the development of China’s small communications satellite constellations.The Hongyun project,one of the five major commercial space projects of CASIC,plans to launch 156 satellites,to build a satellite-borne broadband global mobile internet network and realize the network’s undivided global coverage.The Xingyun project is also one of the five major commercial space projects of CASIC,which aims to build 80 small communications satellites for its constellation operating in low Earth orbit,to enable a narrow-band communications capability giving global coverage.The Hongyan global satellite constellation communications system,which was proposed by CASC,will consist 300 small satellites in low orbit providing a global data service processing center,with all-weather,all-time and constant two-way communications capability in complex terrain conditions.The Yinhe-1 will be built by Galaxy Space,which will be a constellation network of thousands of 5G communications satellites at a 1,200 km orbit.

    In the field of remote sensing,small satellite constellations have become the entry point and focus for commercial capital to enter the field of space remote sensing.The continuous improvement of its commercialization is not only reflected in the acquisition,reception,processing and analysis of massive observation data,but also in the provision of personalized and customized information services for customers.The Jilin-1 satellite constellation is the core project under construction of the Chang Guang Satellite Technology Co.,Ltd.It is an important optical remote sensing satellite constellation in China,it has been widely used in land and resources monitoring,land surveying and mapping,smart city construction and other fields.The Zhuhai-1 satellite constellation is a commercial remote sensing micro-nano satellite constellation launched and operated by Zhuhai Obit Aerospace Technology Co.,Ltd,which is the first satellite constellation constructed and operated by a private listed company in China.The cubesat-based Xiaoxiang-1 series remote sensing nanosatellites are jointly developed by the Spacety Aerospace Co.,the Beijing Institute of Aerospace Long March Vehicle under the China Academy of Launch Vehicle Technology (CALT)of CASC and the Academy of Opto-Electronics (AOE)of the Chinese Academy of Sciences.

    3 PROBLEMS IN THE OPERATIONS OF SMALL SATELLITE CONSTELLATIONS

    3.1 Problems in the Operations with Tracking Telemetry and Command (TT&C)

    In recent years,the number of small satellites has been rapidly growing.Although China has made good progress in the development of small satellites,with more and more small satellites entering into space,in the face of a large number of small satellite constellations,a dedicated TT&C communications network for small satellite systems should be established.At present,most of the existing satellite TT&C automatic test systems in China are of a self-contained closed architecture,limited universal capability,high manufacturing cost,scarce equipment,relatively short life cycle,and without unified standards.The problems can be quantified under the following five aspects.

    1)Compatibility:Due to the large number and variety of small satellite constellations there are multiple characteristics for satellite constellation TT&C.The traditional TT&C approach will not be able to keep up with the demand,and the“One Station,Multi-Satellite”approach will face compatibility issues with multi-satellite integrated control.

    2)Interactivity:The system of TT&C“agency”is relatively complex.The European Space Agency is dominated by SSC and other commercial agencies,while the United States is a parallel development of military agencies and commercial systems.Subject to political and security requirements,the ground systems have less interaction among countries.The existing satellite TT&C system is based on security considerations,and hence it is difficult to interact when external information has to be provided.International networking,information sharing and seamless interaction have yet to be realized.

    3)Standardization:There is no standardization for signal format,data exchange interfaces,mutual transmission and mutual support protocols.Moreover,there are many frequency bands and systems for TT&C,so it is difficult to form a unified global ground standard,so there’s a bottleneck in the unified management of global space traffic.

    4)TT&C of inter-satellite links:Information transmission and exchange between satellites can be realized through inter-satellite links,which can greatly improve the command and autonomous operation ability of a small satellite constellation.However this creates new requirements for the ground TT&C.Consideration must be given to both TT&C for small satellites and inter-satellite links.It is necessary to ensure the transmission of various telemetry,command and ranging signals between satellites.

    5)Space Debris:Space debris refers to the product of human space activities.It includes rocket bodies and satellites,rocket ejectors,other bi-products of the process of executing space missions,plus fragments produced by collision between space objects,etc.At present,there are about 7500 pieces of debris in Earth orbit,mainly in low Earth orbit.Space debris will pose a threat to spacecraft of every country,but the early warning and avoidance information for debris has not been shared globally.

    3.2 Problems in the Application of Small Satellites

    3.2.1 Difficult to scale development

    For a long time,the development of China’s space industry has mainly depended on the demand of military and government public welfare projects.Satellite operation only focuses on the satellite model itself.The owner of a satellite often manages the satellite operation department as a“cost center”,which is similar to the enterprise information department before the emergence of professional IDC (Internet Data Center)business and cloud computing products.This not only limits the development of large-scale and specialized satellite operation as a business,but also creates the situation that the satellite operation cannot be optimized around the demands of its users,hence it is difficult to better serve the overall business of a satellite constellation.

    At present,the technology foundation of most enterprises is weak.In addition to CASIC and CASC,many private enterprises are actively engaged in the field of commercial space,but some enterprises do not have the strong technical strength to develop and operate satellites.In the meantime,most of the commercial satellite constellations are composed of small satellites,their working life on orbit will be generally short,and the prospect of dozens of satellites networking is unsatisfactory.Due to the limitations of industrial management and enterprise technology capability,few commercial aerospace enterprises develop satellite applications and secondary applications.Also,the enterprises which use space technology to create products/services,to meet the demands of consumers and government public services are numbered.

    3.2.2 High application threshold

    In the traditional satellite operation mode,the satellite operation business is only a simple distribution of satellite resources:in satellite communications,it mainly includes transponder leasing,bandwidth/flow control and communications equipment sales;in satellite remote sensing,it mainly includes the sales of remote sensing raw data or rough processed data;in satellite navigation,business is controlled by the government,and a small number of enterprises that carry out satellite based enhanced business,also it mainly provides positioning enhanced signal services and terminal equipment.

    Due to the simple distribution mode of satellite operation at present,it is difficult for traditional satellite operators to provide the right product level,service level or scheme level services or products based on the actual demands of users.Also,for ordinary users,it is also unable to provide satellite resource processing services according to the demands.The above systems improve the technical threshold of satellite service applications,but also limits the use of satellite resources by the majority of industry users and mass consumers.

    3.2.3 Unclear value chain transmission

    At present,the top of the industrial chain of the satellite industry is the satellite owner,which includes satellite manufacturing,satellite launching,ground equipment manufacturing,satellite operational service and satellite applications from top to bottom.Due to the dual constraints of public welfare construction and public welfare services (for example,the BeiDou navigation satellite system,GF satellites and most communications satellites are used to provide public welfare services),the industrial value chain is not clear.For a small number of communications satellites and remote sensing satellites that have been put into commercial operation,the capability (mainly,bandwidth for communications satellites,resolution and return period for remote sensing satellites)and cost are two core elements determining the commercialization of the satellite operation.

    3.3 Policy Issues Related to Commercial Space

    At present,the policy factors restricting the development of the small satellite industry are mainly manifested in two aspects:first,the authority of the satellite TT&C is not open,the military cannot provide control jurisdiction due to policy restrictions,launch resources are scarce,launch license and permit application procedures are miscellaneous;second,the entry threshold and standards for the satellite operation industry are not clear,and there is a phenomenon of blindly following the trend with the help of social capital.

    Since 2014,China has successively issued a series of industrial policies and guidelines related to satellite operation,such as the“Guidance on innovation of investment and financing mechanism in key areas to encourage social investment”,“Medium-and long-term development plan of national civil space infrastructure (2015-2025)”and,“China’s space activities in 2016”.This indicates that the commercial space industry has entered a new era of rapid development.Various kinds of commercial rocket companies,satellite companies,TT&C companies and equipment supporting companies are rapidly springing up.However there is no special legislation for commercial space in the area of small satellites,and the relevant norms of the satellite industry have not been formulated.These include small satellite manufacturing standards,constellation construction standards,frequency orbit allocations,satellite deorbit management,satellite network security and other issues.The incentive policies and cooperation mechanisms for commercial space development have not yet been introduced.

    4 CONSIDERATION FOR THE INDUSTRIALIZATION DEVELOPMENT OF COMMERCIAL SPACE FOR SMALL SATELLITE OPERATION

    4.1 New-Generation Information Technology Based Innovation and Development

    Commercial satellite operational services should take the strategic opportunity of national commercial space development,co-ordinate resources from all sources,integrate satellite services and the new-generation information technology,and provide the“satellite as a service”as new mode of business for satellite owners and satellite users,boost the application of commercial space industry in the field of satellite support and value-added use,drive the rapid development of the space information application industry,and create a new economic growth point.

    4.1.1 Innovative applications of“Cloud,Big data,IoT,AI and Mobile Internet”integration

    With the development of mobile internet,cloud computing,Internet of Things (IoT),Artificial Intelligence (AI),big data and other technologies,global data is growing explosively.As the rapid development of advanced technologies such as AI and big data,the era of big data and AI has begun.The application of"big data +","Internet +" and "intelligent +" will promote the transformation and upgrade traditional industries and the rapid growth of new industries,generating a new engine of economic growth.Under the new era and new environment,big data general services,especially information services based on big data,big data collection,cleaning and processing,integration,visualization,value-added and other services will gradually become a new market hot spot.Since 2015,with the strong promotion by the Chinese government,the big data industry has continued to develop rapidly.

    At the same time,with the rapid development of the satellite industry in the past decade,the number of active satellites in the world continues to increase,the downstream industry becomes the value highland.Similarly the proportion of commercial satellite products and services revenue is also expanding.Due to the late start of China’s commercial space industry,there is still a big gap between the satellite industry market in China and the international market.However,with the continuous maturity of China’s own satellite and service technology,as well as the large-scale application of cloud computing,big data,the Internet of things,artificial intelligence,mobile internet and other new-generation information technologies,the number,quality and capacity of satellites in various industrial application fields are in demand.It’s going to get bigger.

    In the future,with the coming of 5G era,China has realized the importance of satellite communications in 6G era,and started to conduct research to lead the future development of international communications sector.The 6G wireless network will be no longer limited to the ground,but will realize the seamless connection of the ground networks,satellite communications networks and airborne networks,and the peak transmission speed is expected to reach 100 Gbps -1 Tbps.In addition,6G will adopt TeraHertz band communications,and the network capacity will be greatly improved.From the perspective of positioning accuracy,the traditional GPS and cellular multi-point positioning accuracy is limited,which makes it difficult to achieve its accurate deployment for indoor objects.6G will be enough to achieve the high-precision positioning of IoT equipment.It is estimated that the indoor positioning accuracy will reach 10 cm,and the outdoor positioning accuracy can reach 1 m.At the same time,6G will be deeply integrated with AI and machine learning.intelligent sensing,intelligent positioning,intelligent resource allocation,intelligent interface switching and so on,it will become a reality,and the level of intelligence will be greatly increased.

    4.1.2 “Satellite as a service”innovation mode

    Based on the integration of the new-generation information technology,such as the“Cloud,Big data,IoT,AI and Internet”,the new mode of“Satellite as a service”will provide users with the integration of TT&C for commercial space ground services,the integration of communications,navigation and remote sensing of satellite resource services,and integration of“space,sky and ground”for UAV’s and ground-based equipment,providing better satellite resource application scenarios and solutions for the society.“Satellite as a service”will be based on space-based data resources as the core,whether it is to use the new-generation information technology means such as big data analysis and artificial intelligence data mining to realize the vertical appreciation from data to information,to knowledge and to decision-making.Alternatively guided by the user’s functional requirements,business requirements and scheme requirements,so the satellite resources are processed in depth with high degree of freedom,enabling customization and to meet the business attributes.Also not limited to the current independent service systems of communications,navigation and remote sensing,but able to deliver to users in the form of integrated products,services,solutions and flexible business modes,thus achieving the horizontal appreciation of“1+1 > 2”.Hence both approaches require higher requirements for the deep processing and fine processing capabilities of space-based data resources,this requires the construction of a technical support system and supporting infrastructure suitable for the innovative operation mode.

    Integration of TT&C:“Internet+TT&C" mode,will use independently and cooperatively constructed key ground test and transportation control infrastructure to connect TT&C stations with complementary functions and capabilities of different enterprises,research institutions,universities at home and abroad through internet,hence to form a commercial space infrastructure measurement and operational control network,which is compatible with various types of space facilities,multiple frequency bands and systems,and differentiated from the national TT&C network.

    Integration of“communications,navigation and remote sensing”:Due to the rapid development of the digital economy and intelligent industry,in order to meet the multi-functional and multi-purpose needs of users,strengthen the operational ability of operating companies,enhance the value of application services,and increase commercial benefits,commercial space satellite operations need to establish a set of application service systems for the integration of communications,navigation and remote sensing,to provide users with a one-stop space-based information service solution.

    Integration of“space,sky and ground”:In the future,the demand for multi-dimensional comprehensive information resources in the information service industry will increase.Relying on the operation of commercial space satellites,the spacebased network,sky-based network and ground-based network with different sources,different types and complementary performance will be deeply integrated to form a three-dimensional information network with accurate information acquisition,rapid processing and efficient transmission.

    4.2 Exploration of Co-construction and Sharing Mode

    Different from GEO satellites,the LEO small satellite constellation system covers the whole world and can provide satellite services including communications,navigation and remote sensing to every country on the Earth.Repeated constellation construction will inevitably result in the shortage of space resources for low orbit satellites and the waste of satellite service resources.In addition,although the small satellite has the advantages of short development time and low cost,it has short life and poor“anti-destruction”ability which needs to be continuously launched to replenish the satellite constellation system.,The cost of hundreds of small satellites will require a huge capital investment for the satellite owners.

    With regard to satellite ground stations,not only the infrastructure investment is expensive,but also it is restricted by region and can be faced with the problem of a low utilization rate.Therefore,co-construction and sharing of small satellite constellations and satellite ground stations,plus the sharing of manufacturing,launching and measurement and control costs will become a new mode of win-win cooperation.

    The co-construction and sharing of small satellite constellations and ground stations will also bridge the digital divide among countries along the Belt and Road Initiative and develop the digital economy.Most of these countries are sparsely populated with poor infrastructure,but are rich in resources,such as mineral,oil and pastures.Due to the lack of communications,navigation and remote sensing satellite services,these important resources suffer from lack of monitoring.At the same time,the construction of the Maritime Silk Road also needs efficient satellite monitoring that can cover the ocean.A LEO satellite constellation will provide full coverage and reliable satellite services for building the Belt and Road.On the one hand,it will contribute to the development of individual countries along the proposed routes and will serve the purpose of the Belt and Road Initiative for common prosperity.On the other hand,it will provide an effective satellite service for China’s investment and activities in those countries and help Chinese enterprises to“go out”.Thus making more enterprises take part in the construction of the Belt and Road.

    4.3 Co-construction of Industry Ecology

    To build a commercial space ecosystem for co-construction,sharing,symbiosis and win-win,we need to start from the following three aspects:

    1)New technologies promote new forms of satellite operations,thus build an innovative mode of satellite operations with data service as the core,and close the commercial space industry chain.Realize the integrated asset operation mode that gathers all kinds of satellite resources,and comprehensively use the new-generation information technology to obtain added value from data to service in the way of“data+platform+application+service”.

    2)Mode innovation creates a new format for satellite operations.The development of new communications technology,mobile multimedia technology and internet technology will push the satellite communications service into the“internet+”sphere and become the foundation of the space-ground integration.It will further catalyze the integration of information and applications in all industries,comprehensively promoting ideological innovation,technological innovation and industrial innovation,and thus forming a new development form of“satellite internet +”under a commercial space satellite operation service system.

    3)Adhering to the concept of“win-win cooperation in commercial space sector”,to integrate the industrial chain to create a new ecosystem for satellite operations,in order to build a resource cloud,data cloud,service cloud and application cloud for the commercial space industry,and build an open ecosystem service system with military and civilian,domestic and foreign,upstream and downstream satellite equipment manufacturers,satellite data producers,satellite business users and a wide range of satellite application technology developers.

    4.4 Accelerate the Promulgation of Relevant Policies for Commercial Space

    For commercial space,one of the important factors restricting its development is the tight launch opportunities and smooth permit applications.At present,the access conditions for manufacturing and launching commercial satellites are as follows:“The decision of the State Council on the reform of the investment system”,“The regulations of the People’s Republic of China on radio administration”,“The interim measures for the administration of licenses for civil aerospace launch projects”and the relevant regulations and rules of the armed forces,etc.According to the existing application procedures and approval policy,the piggyback launch service of commercial satellites mainly relies on the rocket party or the satellite party who is in charge of applying for approval,and there is no relevant report about a commercial space enterprise applying for launch license independently and successfully.

    In terms of commercial space policies,the state and many local governments have issued plans and opinions to promote their development,but the measures to protect commercial space enterprises are limited,and the organizations that benefit from the relevant policies are mainly traditional industrial departments and scientific research institutes.The United States government has formulated and implemented a feasible preferential systems for commercial space in terms of technology transfer and service procurement,which provide more opportunities for commercial space enterprises to participate in space activities.These measures are also important factors for commercial space companies such as SpaceX to grow and become stronger.Therefore,China needs to establish laws and regulations matching with the development of commercial space and provide more opportunities for commercial space enterprises to participate,promoting the standardization and rapid development of commercial space enterprises.

    We suggest that the relevant state departments should formulate relevant policies to encourage the operations of commercial space small satellites as soon as possible,including industry access and operation qualification license.We call on all enterprises in the commercial space industry to open their technology systems,jointly formulate relevant technical standards,realize system interconnection,and jointly organize a spacebased network to serve China and the world.We call on the upstream and downstream participants of the industrial chain to gather wisdom and strength,build an open ecological service system for commercial satellite operations,and a win-win commercial space industry ecology,working together to push China’s commercial space industry to a new level.

    5 CONCLUSIONS

    At present,with the rapid development of commercial space in China,how to combine the satellite operational service with the new-generation information technology to solve customers’ demand pain points will become the main development goal.As a bridge connecting the upstream and downstream participants of the commercial space industry,the satellite operational service plays a role of connecting the preceding and the following,driving the common development for a commercial space industry and building the industry ecology.At the same time,we call on the relevant departments of China to speed up the process of space legislation,formulate relevant policies to encourage the operations of commercial space small satellites,and promote China’s commercial space capability to a new level.

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