Architecture

Technical decisions and network design for LA-Mesh.

Network Topology

Fully meshed topology with managed flood routing. Every node can relay for every other node. High-power Station G2 routers on elevated sites extend coverage, T-Deck clients participate as both endpoints and relays, and the FireElmo-SDR Pi HAT handles bridge/gateway duties to external networks.

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Station G2 Link Budget

30 dBm TX + 6 dBi antenna = 36 dBm EIRP. Max path loss: 171 dB. Estimated range: 20+ km line-of-sight.

T-Deck Link Budget

22 dBm TX + 2 dBi antenna = 24 dBm EIRP. Max path loss: 160 dB. Estimated range: 5-10 km line-of-sight.

Hop Limit

Set to 5 (optimized for LA-Mesh coverage area). Higher than default 3 to ensure full L-A area reach.

Channel Architecture

IndexChannelPurposePSK
0LA-MeshPrimary community channelUnique 256-bit (shared in-person)
1LA-AdminOperator coordinationSeparate unique 256-bit
2LA-EmergcyEmergency use onlySeparate unique 256-bit

PSKs are never transmitted digitally. Shared face-to-face at community meetups and rotated quarterly.

LA-Mesh - Community LoRa mesh network for Southern Maine

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