Surveillance for a variety of applications in dynamically changing civilian and military environments raises a great demand for innovative sensors and sensors configurations based on cutting edge technologies, such as knowledge-based (KB) signal and data processing, waveform diversity, wireless networking, robotics, advanced computer architecture, and supporting software languages [1]. Improved sensor signal and data processing will be gained from KB and a priori information, multiple processing paradigms, and sensor fusion. KB systems (KBSs) use prior knowledge to improve the performance of deterministic and adaptive systems. While the exact form of this prior knowledge is problem dependent, the KBS consists of a knowledge base containing information specific to a problem domain and an inference engine that employs reasoning to yield decisions. KBSs have been built; some are very complex with thousands of rules while others are relatively simple and designed to tackle very specialized tasks.