Propagation loss and adaptive power control for a broadband-CDMA communication system in a mobile tactical environment

It is pointed out that the battlefield of the future requires the soldier as well as the command post to be mobile. To maintain high quality, LPI communications in this environment requires a spread spectrum system to use fast acting adaptive power control (APC). In addition, proper design requires a thorough knowledge of propagation loss vs. distance. The authors show that the standard loss model, where P_R=P_S (d/d₀)^-n and n=2 for free space or 3 for the Hata model, is incorrect. A correct model is presented with experimental verification. In addition, the authors show that an open-loop APC provides fast acting, linear operation when using broadband-CDMA (code division multiple access) with a chip rate of 24 Mchip/s