Synonym integrated circuit. 2. In satellite communications systems, the smallest element of data in an encoded signal. 3. The most elemental component of a spread spectrum signal when it is decompressed in time; that is, the longest duration signal in which signal parameters are approximately constant. . 4. In micrographic and display systems, a relatively small and separate piece of microform that contains microimages and coded information for search, identification, and retrieval purposes.