LunaNet Signal-In-Space Recommended Standard – Augmented Forward Signal (LSIS – AFS)

Description

The LSIS–AFS standard defines how lunar orbiters or surface systems broadcast a unified navigation and timing signal to support future missions on and around the Moon. It provides a framework for creating an enhanced, interoperable “forward signal” that spacecraft, rovers, and astronauts can use for more accurate positioning, timing, and situational awareness.

1. Signal Definition & Characteristics

 - Specifies the modulation schemes, signal structure, frequencies (e.g., 2483.5–2500 MHz band), and waveform architecture for the AFS broadcast.
 - Ensures that multiple LunaNet Service Providers (LNSPs) broadcasting AFS signals in proximity can be interoperable.
 - Supports both data and pilot channels for robust navigation and timing reception.

2. Navigation Message Specification

 - Defines how navigation data (e.g., satellite ephemeris, clock information) is formatted within the AFS.
 - Requires message structures that support users in computing position and time solutions.
 - Includes provisions for optional future extensions (e.g., improvements to ephemeris or timing formats).

3. Interoperability & Compliance

- Adopting this recommended standard is voluntary in principle, but any provider claiming compliance must fully conform to the defined specifications.
- Ensures consistent behaviour across different provider implementations in a multi-node lunar network.

4. Scalability and Evolution

 - Designed to support diverse lunar architectures (different orbits, surface assets).
 - Allows flexibility for service providers to implement mission-specific features, provided interoperability is maintained.

5. PNT Functionality

 - Enables a GNSS-like PNT service tailored for lunar operational environments (e.g., orbiters, surface rovers, astronauts).
 - Guarantees baseline PNT performance and network participation for compliant nodes.