The use of space is changing rapidly; commercial opportunities are expanding into new orbits and lower launch costs are making space more accessible than it has ever been. Consumer demand for connectivity is seemingly driving a huge portion of investment; both consumers and businesses are building connectivity into every facet of daily routines, and this must be supported by affordable and resilient communication systems. Numerous new entrants are submitting plans to overhaul commercial space, with many intended for Lower Earth Orbit. The shape of existing systems and networks are having to adapt to enable operational viability and, therefore, important questions are now being raised; are the tools available suitable for this new way of working?
Traditional challenges in new scenarios
The satellite has always required technical solutions to manage and maintain resilient services. Often, issues within satcom are caused by inefficiency at the teleport. Radiofrequency interference (RFI) has been an ongoing challenge within the industry that has been thoroughly researched. Within GEO networks, human error and poor-quality equipment were often to blame, with mispointing and signal degradation negatively impacting neighbouring satellite users. Many mitigation tools have been created within the last decade, with testing, validating, and monitoring antennas being core to the reduction of RFI incidents.
When evaluating the ground segment within LEO, there are clear lessons to be learnt from GEO. However, there is added complexity due to the dynamic nature of the LEO ground segment. Due to the lower orbital altitude of LEO, satellites will be switching from one teleport to the next to deliver a continuous feed and therefore the antenna system itself becomes dynamic. The industry’s previous experience of the introduction of dynamic teleports suggests that the challenge will be substantial; when COTM antennas were introduced into GEO networks, there was a surge in incidents of RFI. Importantly, only 1% of deployed GEO antennas are dynamic, therefore this considerable increase in RFI is notable and must be reflected in how we manage LEO’s ground network. Subtle changes within pointing can have a huge impact on RF signals, and this can be magnified by the scale of infrastructures in LEO. With a significant increase in the number of satellites within the ground segment, antenna management becomes a key consideration within the business strategy. Small errors could quickly develop into significant losses of services which would ultimately impact financial profitability and user experience.
How drones will improve the LEO ground network
Managing this critical part of the satellite infrastructure is going to require new methods which step away from traditional testing and validation. There is a crossover between GEO and LEO methods, with static tests monitoring similar data for both orbits. However, LEO has considerably more data to manage due to the antenna tracking a moving signal; this requires additional testing of the dynamic pointing systems. Additionally, tracking accuracy and satellite acquisition quality will need to be monitored to ensure the integrity of the system. The testing of LEO ground segments requires a full raster view of the antenna and not just principal cuts; the entire performance of the dish will be used for tracking, and therefore needs observing.
This increase in complexity within the testing regime, paired with the number of teleports within the LEO infrastructure means that new solutions are required to make testing accessible. Traditional testing methods in which antennas are relocated to testing facilities are costly in both terms of transportation and downtime, whilst results are not factoring in the impact of the antennas own environment. This could result in an underperforming antenna passing tests at the facility and continuing to experience operational issues due to environmental factors, such as reflections, geographical features, or other nearby teleports. Bringing testing on-site is clearly favourable. Drones are now being used to deliver on-site testing for antennas at a competitive cost. LEO satellite communications company, OneWeb, is utilising UAS technology to perform verification of its ground segment antennas ahead of the global rollout of its LEO constellation. The tests are performed by the drone, which mimics the satellite to review antenna performance through data collection. The data can then be processed and mapped utilising software to create detailed reports on performance. This is suitable for LEO ground networks as UAVs deliver flexibility within testing:
- Drones can be used to create testing paths that mimic the movement of satellites, enabling their use within LEO
- UAV testing can be performed on-site, therefore the results consider environmental influences
- UAVs can perform raster, azimuth, and elevation cuts to ensure that the performance of the entire dish is reviewed
- Drones meet LEO’s Ku and Ka-band requirements
- UAV testing is cost-efficient as there is minimal downtime with fewer logistical challenges
The wider picture: why testing matters
Beyond the obvious need for affordable testing within LEO due to the number of teleports and their complexity, drones also enable ground segment operators within other orbits and industries to access testing without creating a financial imbalance within business use-cases. Testing regimes must be cost-effective to promote best practice within the industry. Without this accessibility, there is a risk that some operators will run teleports to a ‘good enough’ standard, without reviewing the potential impact this could have of neighbouring users. This is also true with new technologies at the ground. With a rise in the use of Flat Panel Antennas expected within the satellite industry, it is necessary for FPA operators to have access to the shame rigorous testing tools available to parabolic antennas. Drones offer the wider scope of testing required by FPAs to keep track of pattern changes, as well as in-depth testing at critical operation points. For satellite to be truly efficient, every user must aim for the highest standards and providing access to low-cost tools is the most productive way of promoting this.
The importance of accessible testing regimes
LEO and Newspace are going to enhance existing satellite networks and transform how satellite is viewed within wider industries and communities. As the industry moves ahead with dynamic antenna systems, dynamic testing solutions are going to enable accessible and sophisticated testing regimes which will help to mitigate RFI and other spectrum challenges at the ground segment. The latest advancements within space could be stifled without an intelligent ground network; it must be prioritised.
Drone solutions are seminal within the satcom ground segment; they enable the delivery and maintenance of complex dynamic networks and infrastructures required for the connectivity of the future. Perhaps, just as importantly, drones provide space users with truly affordable access to testing. As an industry, we must promote best practice and cohesive working at the ground to maximise opportunities being provided by the huge expansion and changes within space-use. Managing the ground is key and drones are proving to be pivotal in amplifying this critical part of the newest infrastructures.
