Physical Layer
Spectrum management
- Thereís no FCC for deployed internets - spectrum coordination still necessary
- 400MHz very popular due to diffraction effects (facilitates some beyond-line-of-sight comm) and moderate free space losses
Tracking antennas
- Need vibration-tolerant phased-array antennas for wideband communication to low-orbiting satellites from mobile nodes traversing rough terrain (albeit slowly) -- Potential contributions by LEO-constellation vendors to support on-the-move users