Research Programs

Inter-Satellite Links using Millimetre Waves

Robust Inter-Satellite Links

This project aims to develop a novel communication system for Inter-satellite links (ISLs) at millimeter wave (mmWave) frequencies (60GHz), compatible with CubeSats and small satellites. Inter-satellite communication is a key enabler of advanced Low Earth Orbit (LEO) constellations that intend to provide high speed connectivity around the globe, especially for remote areas. In such constellations, employing high data rate satellite to satellite links significantly reduces the latency and increases the resilience compared to data relaying via multiple ground stations. ISLs also facilitate connectivity with satellites in other orbits including Medium Earth Orbits (MEO) and Geostationary Orbit (GEO).

This project will also investigate use cases for ISLs supporting satellite to satellite communication in formation flying scenarios where multiple satellites fly together to achieve a single mission. Despite of all the advantages, the design of ISL is a challenging task due to the dynamic relative motions of the satellites and the need to develop high data rate links with constrained Size Weight and Power (SWaP). Accurate pointing and tracking mechanisms are required to maintain the connectivity between multiple satellites.

This will enable simultaneous connectivity between multiple satellites. Use of digital or hybrid beamforming will eliminate the need for mechanical beam steering (gimbals). This project will also investigate beam tracking techniques (e.g., monopulse tracking). The phased array antennas with beam tracking capability will then be able to track the transmitter as it moves to maintain connectivity.

P1.28

Project Leader:
Dr Jeewani Kodithuwakkuge, Defence Science and Technology Group

Participants:

Integrated Tactical Communications (ITC)

Dynamic Payloads – RF & Spectral

Secure, reliable, timely and resilient access to information is critical to success in any modern enterprise. This is especially true for military operations across the spectrum from humanitarian assistance and disaster relief (HADR) to battle in highly contested and congested environments.

Currently, the Australian Defence Force relies upon technology developed in the 1970’s to provide network connectivity for its arguably most at risk deployed forces. These systems have well known limitations yet there has been limited research into alternate technologies to support command and control and situational awareness for the tactical warfighter. The project seeks to identify and develop technology for advanced satellite communications as a long-term option to replace or augment these current high mobility satellite communications services.

The project builds on previous SmartSat funded research with a clear focus on three critical technologies to address this gap:

  1. Flexible and adaptive communications waveforms designed for the tactical user
  2. System wide network management to optimise resource allocation for capacity, coverage and resilience
  3. Reconfigurable, agile coverage using multi-frequency, multi-beam antenna arrays (pending future external funding)

This project will refine designs of the tactical communications waveform and initiate research into algorithms that optimise coverage and capacity of heterogeneous/hybrid satellite constellations including an initial demonstration implemented in software. The aim is to accelerate the technology development and understand risks in order to define a follow-on project, funded externally to SmartSat, that will develop a prototype space payload capable of integration with an experimental satellite. This subsequent phase will use the results from this project to inform the agile, multi-beam, multi-band phased array design and the development of initial user terminals. It is expected maturing this technology to the point it can be demonstrated in space will cost $5M – $10M and take three years. This is beyond the resource available from SmartSat so this project will include the
submission of a bid for Defence innovation/prototyping funding to support maturation of the critical underlying technology from TRL4/5 to TRL8.

The target technology demonstration and experimentation program for this research is the Defence STaR Shot for Resilient Multi-mission Space (RMS). The demonstration will showcase a game-changing approach to the provision of resilient satellite communications to the tactical warfighter.

Note: Within this project, tactical communications means systems supporting high levels of user mobility which requires the use of very small aperture terminals (e.g. handheld) and the ability to operate over complex RF propagation channels.

P1.30

Project Leader:
Jeff Kasparian, SmartSat CRC

Participants:

Emergency Buddy System

IoT

This PhD project is closely aligned with SmartSat’s I-in-the-Sky Capability Demonstrator and based on results from SmartSat project, Resilient Emergency Search and Rescue (SAR) Communications, Phase 1 and 2 (P1.07/P1.26). The aim of the project will be to integrate the waveform developed into a user terminal that can be suitable for homes and emergency services.

The project is concerned with the technical feasibility of providing robust satellite-based messaging connectivity with potential to scale across thousands of users with compromised or threatened network access. Beacon devices must be low cost and low power, suitable for long life operation on a battery pack. It is exclusively for use during a communications blackout or other emergency. It will support an emergency beacon function and allow a user to send pre-canned messages and, where enabled, text messages, using a mobile phone app tethered to the beacon device. The same beacon device will monitor an outbound broadcast channel, only decoding messages within
the addressed group, which will be defined by geographical area or other metrics. This will forward notifications and messages to the user app on a mobile phone.

Important aspects of the research will be to demonstrate scalability in terms of number of potential users operating within a power and bandwidth limited radio channel and to illustrate how users may interact with a remote operator, either human or a bot. It is envisioned that a medium access control algorithm will be matched against the offered data model and the satellite link characteristics. The focus will be on simple operating procedures suitable for an unskilled, novice user of the beacon, satellite link efficiency, and suitability for global, low latency LEO satellite constellations.

Provision of a real-time interactive service as a subscription free service for emergency purposes is unique and relies on breakthrough in terms of the capability of the satellite link with a very small form factor beacon. Technical challenges include maintenance of the quality of situational awareness data and robustness of critical reporting to support emergency service operations under highly degraded network conditions. During a compounding incident such as a wide area natural disaster, the increase in network traffic may approach capacity and this must be managed with minimal control overheads. Both text messaging and compact sensor data will be supported. In addition, a stretch goal will be to consider transmission of low rate encoded voice (subtoll quality) or even imagery. An experimental demonstration system will be tested over a live satellite with
the existing UniSA ground station terminating the link at the operator end.

This project is undertaken with two end-users in mind – civil emergency services and Defence. The ability to locate and communicate with vulnerable individuals would enable more targeted use of resources in response to major emergency events such as floods as well as SAR activities. With a miniaturised wearable or easily deployable tactical beacon, capable of two-way messaging, the applications of this service align with the Defence Science and Technology Group’s Operating in contested Chemical Biological Radiation and Nuclear Threat Environments STaR Shot. While the small device MVP is under development, engagement with emergency services and other stakeholders will be underway to explore the adoption and facilitation of a wider uptake of this service.

P1.32s

Project Leader:
Associate Professor Philip Branch, Swinburne University of Technology

PhD Student:
Francis Kagai, Swinburne University of Technology

Participants:

Cognitive Satellite Radios

Cognitive Networks

The efficient and reliable utilization of the radio (electro-magnetic) spectrum for communications has been a long-standing problem, and with the introduction of various wireless (terrestrial) and satellite communication systems and technologies it is of utmost importance for us to address the issue of spectrum efficiency and intelligent spectrum sharing to pave way for the future of satellite (radio) communications. Cognitive radio
technology is an enabler to intelligently adopt satellite transmissions and receptions to improve the spectral efficiency by means of dynamic spectrum access (DSA) and to in turn improve the transmission throughput, resilience and the economic cost. Moreover, the broadcasting nature of such (satellite) transmissions and the inability to perfectly filter out in-band interferences have made satellite (radio) transmissions vulnerable, especially for the critical satellite communication infrastructure such as the defence satellite systems.

In this project we propose to develop and adopt advanced cognitive radio techniques for satellite communications to make satellite communication system intelligent and adaptive. This will improve the spectral efficiency of commercial satellite systems and maximise the throughput and availability of critical communication systems in congested and contested situations. The project makes important contributions to future, intelligent space networks that underpin Command and Control and Situational Awareness relating to Defence (including RMS StarShot) interests.

This project represents a substantial work as part of a number of activities anticipated in the cognitive network space. Importantly, the project incorporates a ‘stage-gate’ approach in development to ensure that focus is achieving its research outcomes, maintains industry alignment, and is coordinated with other, current and future-related projects.

P1.27

Project Leader:
Professor Kandeepan Sithamparanathan, Royal Melbourne Institute of Technology (RMIT)

Participants:

Emergency Communications for LunaSAR (RESARC Phase 2)

IoT

This project’s aim is to develop a concept design proposal for communications technology to help shape NASA’s LunaSAR requirements. This will derive from outcomes of the previous SmartSat project P1-07 (RESARC), and provide options to enhance form and function of the distress messaging system components in the challenging lunar environment. The activities consist of review of NASA’s preliminary concept of operations (CONOPS), architecture, operational parameters such as NASA’s sensor message definition, frequency band and satellite orbit characteristics, and constraints including size weight and power (SWaP); performance analysis for the LunaSAR communications subsystems including satellite payload; simulation and prototyping of key aspects, and; capture of design concept for NASA’s review and consideration. The expected outcome is that NASA will be presented with options to adopt best-in-class Australian technology for use within their LunaSAR system.

P1.26

Project Leader:
Dr Mark Rice, Safety from Space

Participants:

WildFireSat Mission and Australian Bushfire Management

Advanced Communication, Connectivity & IoT Technologies

The objective of this project is to assess the suitability of the Canadian WildFireSat mission for Australian Bushfire Management.

P3.28

Project Leader:
Associate Professor Marta Yebra, Australian National University

Participants: