The communication channel in urban operations - A first survey

Military operations in urban environment are in general conducted with dismounted solders, both outside and inside buildings, including below ground in basements and culverts. Situation awareness is essential, position and status of team members are very important information for every soldier. Communications is therefore essential for command and control, and wireless is the only means where radio is the prime technology. Free space optics (FSO) may be an alternative to radio communication in urban areas, due to less jamming and interception sensitivity, high bit rate and no licensing or frequency allocation needed. However, the atmospheric effects, i.e., turbulence and attenuation, limit the availability of free space optics links. Even the radio channel sets limits for present and future wireless communication system. A thorough understanding of wave propagation is important and when calculating the wave propagation a number of propagation mechanisms need to be accounted for, i.e., transmission loss, arrival times, phases, delay spread and correlation bandwidth.