Mesh Radio Node
UHF/S-Band Software-Defined Mesh Radio Transceiver
Short-range software-defined radio (SDR) operating at UHF (390–460 MHz) and S-band (2.0–2.3 GHz) providing the physical/MAC layer for the Ark's local mesh, connecting robots, rovers, sensors, and fixed Ark modules.
Purpose
Establish a fault-tolerant, self-discovering local radio network within ~10 km of the Ark, supporting commanding of mobile assets, sensor telemetry collection, and inter-module data exchange independent of the Earth link.
Context
Multiple mesh nodes distributed across Ark modules and robotic platforms; L3-COM-MESH-ROUT runs the BPv7/DTN routing on top. Designed to be CCSDS Proximity-1 (132.0/211.0/212.0-B) compatible for interoperability with Artemis lunar surface assets, NASA LunaNet 'detection and information' service, and ESA Moonlight relays.
Principles
- ▸CCSDS Proximity-1 is the standard space-link protocol for short-range surface and orbital relay (used by Mars Express → MER/MSL/Perseverance UHF)
- ▸Software-defined radio (SDR) allows protocol updates without hardware changes — essential for 100-year mission and protocol evolution
- ▸UHF (~437 MHz) offers diffraction around obstacles, useful in cratered lunar terrain; S-band (2.2 GHz) offers higher bandwidth but line-of-sight
- ▸Mesh networking provides multi-hop routing and self-healing topology — failure of any single node does not partition the network
- ▸Time-Division Multiple Access (TDMA) coordinated by a synchronized clock minimises collisions; alternative is CSMA/CA
- ▸GMSK and OQPSK provide constant-envelope modulation for power-efficient amplification at the rover/robot end
Typical implementations
- ▸JPL Electra UHF transceiver — used on MRO, MAVEN, Mars 2020 (Perseverance), and lunar plans; CCSDS Proximity-1, up to 2 Mbps
- ▸Iris transponder variants (CubeSat) with UHF mesh capability
- ▸NASA's HDTN (High-Data-Rate DTN) implementation for surface mesh
- ▸Spatiam's commercial DTN over LoRa products for surface networks
- ▸South Korea's KPLO Danuri tested DTN to lunar orbit (2022–2024)
Lunar considerations
- ▸Lunar terrain causes severe shadowing — multi-hop routing via mesh is essential, especially near PSRs (where direct LOS to most assets is blocked)
- ▸Charged dust and electromagnetic interference from solar wind interaction can degrade UHF SNR — diversity and FEC required
- ▸Long mission requires SDR firmware update over the same mesh — bootloader and signed firmware updates critical (L3-COM-CRYPT-AUTH)
- ▸Energy management on mobile mesh nodes (rovers) is tight — low-power sleep modes with periodic wake-up beacon synchronization
- ▸NeuraLunaDTNet (Chakraborty et al. 2024) proposes neural-network routing for lunar DTN, potentially deployable in future updates
Specifications
Functional
| primary function | Bidirectional short-range RF link forming part of mesh network at UHF/S-band |
| inputs | Outgoing packets from L3-COM-MESH-ROUT, RF energy from peer nodes, 10 MHz timing reference from L3-COM-TIME-DIST, DC power from L1-PDM |
| outputs | Radiated RF (up to +33 dBm / 2 W), Demodulated packets to L3-COM-MESH-ROUT, Link quality metrics (RSSI, BER, neighbor list), Doppler/ranging measurements for relative navigation |
| frequency bands mhz | [390, 460], [2000, 2300] |
| rf output power w | 2 |
| data rate kbps min | 8 |
| data rate kbps max | 2048 |
| sensitivity dbm | -116 |
| max link range km | 15 |
| supported protocols | CCSDS Proximity-1, BPv7, IEEE 802.15.4 (alt) |
| modulation | GMSK, OQPSK, BPSK |
| max neighbors | 32 |
Physical
| mass kg | 0.9 |
| dimensions | 120 × 100 × 35 mm |
| materials | Aluminum 6061-T6 housing, Rad-tolerant SDR FPGA (Xilinx Kintex / Microchip PolarFire), GaN PA for S-band, LDMOS for UHF, GaAs LNA front-end, PTFE-substrate matching networks |
| operating temperature c | -40, 70 |
| radiation tid krad | 50 |
Operational
| power consumption w tx | 12 |
| power consumption w rx | 3 |
| power consumption w sleep | 0.05 |
| thermal range c | -40, 70 |
| lifetime years | 15 |
| mtbf hours | 150000 |
| number deployed | 24 |
Interfaces
Provides
- Packet-level transport with neighbor discovery and link metrics
- RF signal to omnidirectional antenna
Requires
- Outgoing packets with destination addressing
- Receive RF aperture
- Time/frequency reference for TDMA slot timing
- 5 V supply, ~12 W peak
Cite this entry
Lunar Ark Codex. "Mesh Radio Node" (L3-COM-MESH-NODE). Retrieved 10 September 2026, from https://lunarark.com/entry/L3-COM-MESH-NODE
Licensed CC-BY-SA 4.0. You may reuse and adapt this entry with attribution, under the same licence.