The Mobile Data Link (MDL) of the Joint Tactical Radio System Wideband Networking Waveform

The joint tactical radio system (JTRS) wideband networking waveform (WNW) is applying the latest advances in distributed ad-hoc networking to a wide range of military applications and platforms. The mobile data link (MDL) provides the channel access for WNW using adaptive TDMA to efficiently schedule transmissions in the face of scarce channel resources, challenging throughput and latency requirements, and changing link conditions. Because of their scarcity, channel resources are reused spatially and concentrated in nodes that are best positioned to relieve congestion. Both allocated TDMA slots and contention slots provide unicast and broadcast coverage that have been optimized for operational groups of nodes on the same channel while allowing selected nodes to bridge between channels. Transmission parameters are adjusted on the fly in response to changes in measurements provided by the signal-in-space (SiS) that reflect signal strength and symbol error rate. This paper provides an overview of the architecture of the MDL, its major functions and unique algorithms, and its adaptability to different operational scenarios based on configuration parameters. It will also present performance results based both on recent lab tests using pre-EDM units and on a shared code simulation model that uses the MDL operational code in a realistic emulated networking environment