Polo Marconi Mesh Gateway Interoperability Gateway Between Analog VHF-UHF Radio Networks and IP Tactical Mesh Networks for Legacy Integration

The Polo Marconi Mesh Gateway is the interoperability gateway designed to resolve the most frequent technology transition problem in Armed Forces and security organizations modernizing their communications infrastructure: the fleet of conventional analog VHF/UHF radios represents tens of millions of dollars in amortizable investment with 15-20 year useful life, while the new IP tactical mesh network architecture (Rajant, TrellisWare, Persistent Systems) provides data and video capabilities that analog radios don't support — but migrating the entire fleet to new digital terminals in a single budget cycle is not feasible.

The Mesh Gateway converts the analog voice transmissions of conventional VHF/UHF radios (bands 30-88 MHz and 136-174 MHz for VHF, 225-400 MHz for UHF) into IP voice packets encoded with MELP (Mixed Excitation Linear Prediction) at 2400 bps — the standard military vocoder that maintains voice intelligibility in combat noise environments at very low bit rates compatible with the available bandwidth in tactical mesh networks — and injects them into the IP mesh network as virtual radio nodes. The user of a TrellisWare TSM-X node or a Rajant BreadCrumb node can speak directly with the analog radio operator without either of them changing equipment or learning new procedures.

The analog-to-IP conversion latency of under 80 ms meets the voice intelligibility requirement for combat communications — above 150 ms latency is perceptible and degrades tactical coordination — and MELP encoding guarantees intelligibility in vehicle engine noise and combat environment without post-processing. The 4 independent radio ports allow connecting 4 analog radios from different bands simultaneously, routing each as an independent channel in the mesh network to specific talk groups.