The type of information being sent has a major impact on energy needs. A National Research Council study looked at how much battery weight is needed to acquire and transmit a particular piece of information.11 For example, it is estimated that about 1 / 100th of a gram in battery weight is needed to perform speech recognition on voice input and transmit the information as text, and about 1/2,000th of a gram to digitize and transmit voice as audio. But compression and transmission of video would require about 10 grams of batteries. The battery weight required to distribute real-time data with full-color video among mobile users in the battlefield would be quite large.
11National Research Council. 1997. Energy-Efficient Technologies for the Dismounted Soldier. National Academy Press, Washington, D.C.