ABSTRACT
Contents 19.1 Introduction ................................................................................................................... 394 19.2 Summary of Benefits of Directionality ............................................................................395 19.3 Key Differences between Military Directional Mesh Networks and MANET ................395 19.4 Platform Use Cases ........................................................................................................ 396
19.4.1 Backhaul/Relay for Airborne Networks ........................................................... 397 19.4.2 Tactical Mesh Networks .................................................................................. 398 19.4.3 Airborne Radio Access Networks ..................................................................... 398 19.4.4 Use Case Summary .......................................................................................... 399
19.5 Physical Layer Considerations ........................................................................................ 399 19.5.1 Latency Due to the RF Propagation Time ....................................................... 399 19.5.2 Doppler ............................................................................................................ 400 19.5.3 Antenna Placement .......................................................................................... 400 19.5.4 Antenna Tracking ............................................................................................ 402
19.6 Data Link Layer Considerations ..................................................................................... 403 19.6.1 RF Power, Range, and Data Rate ..................................................................... 403 19.6.2 Curvature of the Earth ..................................................................................... 405 19.6.3 Spectrum Management .................................................................................... 405 19.6.4 Cosite Interference ........................................................................................... 408 19.6.5 Gender ..............................................................................................................410 19.6.6 Multiple Access Schemes ...................................................................................411 19.6.7 Summary of RF Data Link Layer Considerations .............................................413
19.7 Network Layer Considerations ........................................................................................413 19.7.1 IP Basics ............................................................................................................413 19.7.2 IP Mobility Protocols ........................................................................................414
19.1 Introduction Situational awareness, command and control, and the role of timely information have always been essential to the outcome of wars. Though the implementation specifics of network-centric warfare (NCW) have transitioned significantly since its conceptual introduction in the late 1990s [1], it remains perhaps the defining transformation in military affairs of the last decade. NCW “translates information superiority into combat power by effectively linking knowledgeable entities in the battlespace” [2]. In short, military command and control and thus warfighter effectiveness is optimized by getting the right information to the right entity at the right time. The process of creating a network that spans over increasingly large areas of operation, sometimes globally-from rear command echelons to the edge of the fighting area-is often referred to in defense parlance as the global information grid (GIG) [3,4]. Recent global conflicts have demonstrated just how important information flow is in the conduct of modern warfare and the bandwidths necessary to support the information flow. Key to achieving the vision of the GIG is the need to provide robust, high capacity communications networks at all security levels. Airto-air, high capacity, directional mesh networking is being pursued by defense strategists. One example is the joint aerial layer network (JALN), illustrated in Figure 19.1 [38]. JALN defines a top level architecture critical for solving battlespace connectivity by providing three critical functions: a ubiquitous high capacity backbone (HCB); distribution, access and range extension (DARE), and network transition (gateway) functions. This chapter addresses the unique challenges associated with directional mesh networks and how they differ from commercial networks.[*]
