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Digital communication has proliferated in a big way in the recent years. The advantages of digital communication are improved efficiency, better transmission accuracy, better noise immunity, requirement of lesser bandwidth, transmissionheception equipment. Digital communication in a shipboard application is used for transmission of voice, data and picture between ships in an operational environment where accuracy, secrecy and immunity to noisehnterference is essential. The advent of latest equipment capable of advanced signal processing techniques will result in prolific use of digital communication in shipboard applications.secrecy, and standardisation ofThe paper aims at bringing out various aspects of digital communication vis-a-vis the dense electromagnetic environment that exists on a Naval plafform and their compatibility. The use and applicability of source coding, digital modulatiy techniques, error control coding and data security in mitigating the electromagnetic interference in a ship borne environmen? are discussed. The various problems of co-ChanneVadjacent channel interference and the effect of random/burst noise on a digital communication system are also brought out. Achieving immunity of digital communication to interference by use of various spread spectrum techniques is also discussed. IntroductionMost tactical communication in Naval applications are provided by HF, V/UHF and Satellite links. HF links are used for long haul communication between ship-to-ship or ship-toshore to . provide Beyond-Line-of-Sight (BLOS) ranges. WUHF links are used for line of sight communication with limited ranges. The service requirement of video transmission is only supported by V/UHF and Satellite links owing to higher data rates. The factors affecting a digital communication system for HF and V/UHF links are brought out in the paper due to their prolific use in the shipboard communications.

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