What is one characteristic of tactical communication systems?

Portability for use in variable environments is a key characteristic of tactical communication systems because these systems are designed to be deployed quickly and effectively in a range of operational settings, often where conditions can change rapidly. The ability to set up and use communication equipment in diverse terrains or locations—such as during combat operations, disaster response, or humanitarian missions—is essential for maintaining effective communication and coordination among forces. This mobility allows for flexibility and ensures that communication capabilities are maintained regardless of the environment, whether it be urban, mountainous, or remote.

In contrast, the other options do not align with the fundamental design principles of tactical communication systems. For instance, being dependent on fixed installations would limit their operational capability in dynamic situations. Similarly, a focus on large size might compromise portability, and the exclusive use of analog signals does not reflect current technological advancements that include digital systems for improved efficiency and versatility. Thus, portability stands out as a defining aspect of tactical communication.