Optimizing high-volume data downlinks with HaloNetTM

Traditionally, direct-to-Earth (DTE) services have supported bulk downlink of large data sets, such as those produced by Earth observation satellites, or uplink of software/firmware updates of payload components. However, as advanced technologies are introduced and support space-based missions, it’s created an opportunity for operators to adapt their approaches and deliver innovative communications capabilities to support them.

Viasat’s HaloNet capabilities portfolio combines the large data transmission capabilities of DTE services with space-to-space data relay to support timely information dissemination and cueing of space assets in response to detection of events of interest or changing mission priorities.

HaloNet integrates relay, ground access, and field operations into a single adaptive architecture that meets the current and evolving needs of near-earth mission communications. DTE connectivity is provided via traditional fixed Earth stations and through deployable, mobile satellite gateways - expanding coverage areas, reducing communication contact window delays, and enabling access for distributed command posts that may need secure communications paths. Complementing the L-band Tracking, Telemetry, and Command (TT&C) and Ka-band High-Capacity Data Relay Services to provide a full range of space-ground transport services, the DTE network is ideal for ultra-high rate payload data downlink.

The fixed Earth stations utilize the existing Viasat Real-Time Earth (RTE) service to deliver a turnkey Ground Station as a Service (GSaaS) capability, providing secure connectivity services for spacecraft missions in low Earth orbit (LEO), medium Earth orbit (MEO), and geostationary orbit (GEO). The globally-distributed network of direct-to-Earth ground stations delivers high performance TT&C and payload downlink. Each ground station is equipped with precision-controlled antennas supporting S-, X-, and Ka-band configurations, offering government and commercial operators a scalable, secure path to transmit data to and from Earth.

By blending a mix of space-to-space links, including L-band and Ka-band alongside DTE, Viasat is addressing existing and emerging challenges in a scalable manner. The data relay services can be used for TT&C, software and firmware updates, and high-priority payload data downlink, while DTE resources are available for bulk transfer of large, but less time sensitive data sets such as raw imagery.

Maintaining the security of data in transit is a significant consideration. Collected data may be proprietary or have national security implications, which imposes strict confidentiality, integrity, and availability requirements - both on data handling and service management. Additionally, maintaining the data sovereignty, landing data in trusted locations, and properly authenticating all nodes and links in the end-to-end data path are key to communications confidentiality and integrity. Viasat’s RTE operates as a “bent-pipe” architecture to transmit encrypted information, reducing the need for crypto solutions at ground antenna locations and ultimately shrinking the security footprint.

As users review their data transmission requirements and select services, they should conceptualize communications in terms of higher-level data delivery goals and constraints, rather than low-level transport details such as channel bandwidths and link protocols or specific ground station locations.

A unified service model like HaloNet enables users to implement standardized, transport-agnostic service interfaces for sending and receiving data across all transports, viewing service metrics and events, and, where relevant, scheduling transport activity.