Mesh sats for ad-hoc global communication without borders

Orbital plan

LoRa sat proposal

Based on your design objectives and constraints, here is a proposed configuration for your LoRa-based micro-satellite network architecture:

🌍 Orbital Constellation Configuration

1. Equatorial Low-Elevation GEO-Orbit Set (Stationary Set)

  • Orbit Type: Geosynchronous Equatorial Orbit (GEO)
  • Altitude: ~35,786 km
  • Purpose: Continuous coverage over equatorial regions with minimal Doppler shift, ideal for fixed ground stations.
  • Initial Nodes: 10 satellites spaced ~36° apart longitudinally
  • Power Profile: 300W, PV + ion thrusters for minor station-keeping
  • Antenna Configuration: Directional phased array toward Earth + wideband omni relays for satellite interlinks

2. Polar Orbiting Set

  • Orbit Type: Sun-Synchronous Polar Orbit (SSO)
  • Altitude: 500–900 km
  • Inclination: ~98°–100°
  • Purpose: Near-global coverage; high revisit rates for poles and mid-latitudes
  • Initial Nodes: 20 satellites evenly spaced
  • Coverage Strategy: Sweep Earth in vertical strips, ideal for sensor data collection
  • Inter-satellite Communication: Optical or RF crosslinks with adjacent nodes and GEO set

3. High-Elevation Criss-Cross Orbits

  • Orbit Type: Medium Earth Orbit (MEO), inclined at ±60° from equator
  • Altitude: ~20,000–24,000 km
  • Inclination: ~60°–65°
  • Purpose: Redundant coverage, orbital diversity, relay avoidance of congested low Earth orbits
  • Initial Nodes: 30 satellites (15 per inclined plane)
  • Form: Intersect polar paths to allow cross-routing via diagonal paths, improving global coverage mesh
  • Antenna Setup: Omnidirectional with gain optimized for satellite-to-satellite interconnectivity

📡 Technical Specifications

  • Frequency: 915 MHz ISM band (LoRa, sub-GHz)
  • Transmitter Power: 300W per satellite (burst or duty-cycle modulated for compliance)
  • Modulation: Chirp Spread Spectrum (CSS)
  • Antenna Gain Budget: Earth-facing directional antennas: 12–15 dBi; omni node relays: ~3–6 dBi
  • Absorption: Photovoltaic panels + ion drive integration for energy management and attitude control

🛰️ Inter-Satellite Relaying and Redundancy

  • Legacy Satellite Nodes: Full-body omnidirectional relays for low-speed data pass-through
  • Regulatory Shielding: Apply 3% link margin derating for ITU + national regulatory zones; reallocate power and downlink frequency dynamically based on geographic location and orbital path

🌐 Deployment Strategy

  • Launch Phases:
    • Phase 1: 10 GEO sats (stationary control + redundancy nodes)
    • Phase 2: 20 polar SSO satellites for Earth coverage
    • Phase 3: 30 criss-cross inclined orbit satellites for mesh integrity
  • Minimum Viable Network: 24 satellites (6 GEO, 6 polar, 12 inclined)

📊 Justification

Orbit Type Coverage Latency Collision Risk Role GEO Equatorial only High Low Base stations & routing control SSO Polar Global Low Medium Data collection & routing Inclined MEO Global w/ overlap Medium Low Relay routing & redundancy