The second SpectrumX flagship project will focus on creating models, measurements, and analysis that are relevant to the coexistence of scientific and critical systems with satellite systems and constellations. The visibility of satellites poses significant coexistence challenges as the scale of these systems has begun to demonstrate dramatic increases. This process is driven by corresponding decreases in the mass cost to orbit and changes in satellite production, launch, and control capabilities. All satellites carry radio systems and many constellations are targeted at providing communications capabilities and services using highly capable phased array antennas. Satellite systems also have unintentional radio emissions from control components, data buses, and system oscillators. Such emissions pose a significant coexistence challenge for many passive uses of the radio Spectrum.
Scientific systems are very often highly sensitive and can be vulnerable to both the direct and aggregate emissions from the rapidly growing number of orbital emitters. For ground based systems, it was previously possible to use remote terrestrial locations to isolate sensitive systems from interference. For scientific satellite systems the visibility of other satellites from orbit was generally transient in nature. These conditions no longer hold as constellation densities increase. Both the direct and aggregate effects as satellite constellations increase in scale have created a range of potential interference issues. Objective understanding and prediction of impacts is not yet possible due to several critical gaps. These gaps include:
- A Lack of Prediction Capability for Direct and Aggregate Effects
- Limited Knowledge of Harmonic, Spurious, and Unintended Satellite Emissions
- Inadequate Rights and Coexistence Mechanisms to Coordinate Emissions at Scale
- Unknown Impacts on Critical Scientific Systems and Models
To help address these gaps, the Scientific Coexistence Flagship effort will take initial steps to investigate:
- Coexistence Models for Scientific Systems
- Experimental Measurements of Existing Systems
- Coexistence Policy and Rights Benefits and Challenges
Major work element areas will initially include: (1) Direct and Aggregate Effects of RFI on Weather Forecasting ; (2) Megaconstellation RFI; (3) Scientific System Impacts; (4) Economic, Policy, and Rights Incentives for Scientific Coexistence.
