Naval Shipboard Communications Systems

The mission of the U.S. Navy, stated in Title 10, U.S. Code, is to be prepared to conduct prompt and sustained combat operations at sea in support of the U.S. national interest. This also means that the U.S. Navy must effectively assure continued maritime superiority for the United States. Derived from that are the Navy's two basic functions: sea control and power projection. Effective communications is vitally important to fulfill this mission, and for this the U.S. Navy depends on a worldwide Command, Control, and Communications (C3) capability. Naval communications is constantly evolving and adopting modern technology. Satellite communications and modern networking is a part of the repertoire of naval communications technology. The development of communications and data processing technology is fostering significant changes in the manner in which the Navy is communicating among ships and between ship and shore. The chain of operations from sender to receiver includes message format processing, relaying to a communications center, protection to prevent unauthorized intrusion and to guarantee transmission integrity, modulation for optimum sending over the medium, transmission, reception, removal of the protection, and distribution to the recipient. Naval shipboard communications combines advanced technology with operational procedures, and uses ruggedized equipment that can be maintained with limited resources in the harsh environment of the sea. All aspects of engineering disciplines are applied to provide this essential capability to the U.S. Navy. It includes not only technological aspects but also operational procedures, configuration control, and logistic support considerations. The most advanced technology has little value if it cannot be operated and maintained by naval personnel under stressful conditions. This book focuses on shipboard communications. Shipboard communications has an exterior component, dealing with antennas, transmitters, and receivers, in short the classical exterior communications (EXCOMM). It also has and intraplatform component dealing with the shipboard distribution system, the communications processors in the communications rooms, and the procedures for processing messages. In this book we discuss the technologies and circuits of all frequency regions used for naval communications, from ELF to optical frequencies. The shipboard EXCOMM spans a wide spectrum. At the low end of the spectrum, ELF with frequencies from 70 to 80 Hz penetrates seawater and allows very narrowband transmission to submerged submarines. In the VLF region from 10 to 30 kHz, the Navy operates long-range narrowband TTY circuits largely unencumbered by the vagaries of propagation. HF supports long-distance circuits, VHF, UHF, and SHF support line-of-sightcommunications among ships and between ships and aircraft. EHF, 30 to 300 GHZ, supports the latest satellite communications technology. Optical frequencies, at the high end of the spectrum, penetrate seawater and can be used for communications to submerged submarines. A modern Navy ship has many communications, radar, guidance, and weapons systems, all of which require antennas. These antennas, many of which are clearly visible when one sees a naval ship, others of which are small, unobtrusive structures blending with the ship's hull, transmit and receive electromagnetic signals that can interfere with each other severely. Electromagnetic compatibility (EMC) is an essential part of shipboard electronic engineering to assure that naval communications are functioning well. Intraplatform communications provide the interfaces through which the electromagnetic signal is brought from the topside antennas into the ship and are distributed within the ship for processing the communicated information. Protocols, that is, message formats and methods to accomplish the data and message transmission, are essentiaKim, J. C. is the author of 'Naval Shipboard Communications Systems' with ISBN 9780136134985 and ISBN 013613498X.