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Radio Communications System

The Radio Communications System (RCS) consists of several exterior communications subsystems which, in combination, provide all exterior communications requirements for the ship with the exception of the Special Intelligence Communications requirements. The RCS subsystems are turnkey installations and consist of the following subsystems: High Frequency Communications System, Very High Frequency Communications (VHF Comms) System, Ultra High Frequency Line-of-Sight Communications (UHF LOS Comms) System, Ultra High Frequency Satellite Communications (UHF SATCOM) System, Extremely High Frequency Satellite Communications (EHF SATCOM) System, Super High Frequency Satellite Communications (SHF SATCOM) System, Communications Support Segment (CSS), Naval Modular Automated Communications System (NAVMACS) II, and the Bridge To Bridge Communications System.

The High Frequency Communications System consists of the High Frequency Radio Group (HFRG) is a fully automated subsystem of the external radio communications system (RCS) aboard surface ships. The HFRG operates in the Very Low Frequency (VLF), Low Frequency (LF), Medium Frequency (MF) and High Frequency (HF) frequency bands and supports full duplex, half duplex and simplex operation for tactical and long-haul voice, interrupted continuous-wave, teletype and digital data communications in the Lower Sideband (LSB), Upper Sideband (USB), Independent Sideband (ISB), Amplitude Modulation Equivalent (AME) and Link 11 modes of operation. The HFRG consists of three subsystems: the transmit subsystem, the receive subsystem and the control/monitor subsystem (CMS).

The Transmit Subsystem operates (in increments of 10 Hz) in the frequency range of 2 Mhz to 30 Mhz and is used primarily for broadband circuits. The Transmit subsystem is designed to allow all exciters to operate in the Link 11 mode, but contains the assets required to support two (2) 1kW narrowband circuits which are the primary HF Link 11 circuits.The operational capabilities of the transmit subsystem require both broadband and narrowband antennas. The operational configuration of the transmit subsystem is accomplished in response to commands from the CMS and frequency changes (except narrowband) are completed in less than 100 milliseconds. The transmit subsystem reports to the CMS when the system is configured and also reports detected failures.

The Receive Subsystem operates (in increments of 10 Hz) in the frequency range of 14 Khz to 1.619 Mhz and 2 Mhz to 30 Mhz. The receive subsystem requires at least two broadband antennas and 1 or 2 additional antennas dedicated to the use of the Ship Signal Exploitation Equipment (SSEE). The operational configuration of the receive subsystem is accomplished in response to commands from the CMS and frequency changes are completed in less than 20 milliseconds. The receive subsystem reports to the CMS when the system is configured and also reports detected failures.

The Control/Monitor Subsystem is the backup point of control for the HFRG when the system is being controlled by the Surface Ship Automated Communications Control System (SSACCS) (part of the Communications Support System (CSS)). The SSACCS normally controls the HFRG through an interface with the CMS, but if the SSACCS becomes inoperable the CMS automatically assumes the functions of remote control, performance monitoring, test, operator interface, and display of the operational characteristics. The CMS is used to send configuration commands to the transmit and receive subsystems and, in turn, receive configuration completion and operational characteristics from these subsystems.

The Very High Frequency Communications (VHF Comms) System is utilized to transmit and receive tactical, operational and administrative information (both voice and data) in the VHF range (30-300 MHz). The VHF Comms System primarily supports line-of-sight (LOS) communications between accomplishing units and is comprised of several different Radio Groups or subsystems. Most of the Radio Groups are functionally interchangeable and therefore are not individually dedicated to a specific circuit or function.

The Ultra High Frequency Line-of-Sight Communications (UHF LOS Comms) System is utilized to transmit and receive tactical, operational and administrative information (both voice and data) in the UHF range (300 MHz - 3 GHz). The UHF LOS Comms System is capable of operating in either the UHF LOS or UHF Satellite Communications (UHF SATCOM) mode. Most of the UHF LOS equipments are functionally interchangeable and therefore are not individually dedicated to a specific circuit or function.

The Ultra High Frequency Satellite Communications (UHF SATCOM) System provides communication links, via satellite, between designated mobile units and shore sites worldwide. The UHF SATCOM system is one of three SATCOM systems installed and operates in the UHF range. The SATCOM systems, combined, represent a composite of information exchange systems that use the satellites as relays for communications and control as well as quality monitoring subsystems that provide data to manage satellite resources. The shipboard SATCOM configurations vary in size and complexity and dependent upon the message traffic level, types of communications and operational missions of the ship. The UHF SATCOM system provides multichannel satellite transmission and reception and is comprised of two distinct, but related, subsystems: (1) UHF SATCOM receiving set and (2) UHF SATCOM transceivers and UHF Demand Assigned Multiple Access (DAMA) equipment.

The UHF SATCOM receiving set is the UHF component of the High Speed Fleet Broadcast (HSFB) and is used to receive the downlink Fleet Broadcast signal and demultiplex it into the different Fleet Broadcast baseband circuits.

The UHF DAMA equipment is used to multiplex various baseband equipments and interface them with the UHF SATCOM transceivers. The multiplexing provides the capability for more satellite circuits to use a single UHF satellite channel thereby increasing the circuit capacity of the satellite.

The Extremely High Frequency Satellite Communications (EHF SATCOM) System provides communication links, via satellite, between designated mobile units and shore sites worldwide. The EHF SATCOM system is one of three SATCOM systems and operates in the EHF range (30-300 GHz). The SATCOM systems, combined, represent a composite of information exchange systems that use the satellites as relays for communications and control as well as quality monitoring systems that provide data to manage satellite resources. The shipboard SATCOM configurations vary in size and complexity and dependent upon the message traffic level, types of communications and operational missions of the ship. The EHF SATCOM system is a general purpose satellite communications terminal that provides survivable, jam-resistant, low probability of intercept communications for secure voice, teleprinter and data circuits. The system provides four primary transmit/receive channels, four secondary transmit/receive channels and four receive only channels.

The Super High Frequency Satellite Communications (SHF SATCOM) System provides communication links, via satellite, between designated mobile units and shore sites worldwide. The SHF SATCOM system is one of three SATCOM systems installed and operates in the SHF range (3-30 GHz). The SATCOM systems, combined, represent a composite of information exchange systems that use the satellites as relays for communications and control as well as quality monitoring subsystems that provide data to manage satellite resources. The shipboard SATCOM configurations vary in size and complexity and dependent upon the message traffic level, types of communications and operational missions of the ship. The SHF SATCOM system provides highly reliable, high capacity, long range ship to shore communications with a high degree of immunity to jamming and direction finding.

The Communications Support Segment (CSS) is a communications sub-architecture that enhances battle force communications connectivity, flexibility, and survivability through multi-media access and media sharing. The CSS is the major vehicle for integrating all of the U.S. Navy's Communications assets into the Copernicus Architecture. The CSS defines standard hardware and interfaces, requirements for reusable software, standard protocols, and a security policy that combines Communications Security (COMSEC) and Computer Security (COMPUSEC). The CSS permits users to share total network capacity on a priority demand basis in accordance with the tactical commander's current communications plan. Automated network monitoring and management capabilities are also provided by the CSS to assist operators in the real-time allocation of communications resources according to selected criteria (e.g., suitability, Antijam (AJ), priority).

The Naval Modular Automated Communications System (NAVMACS) Model II , commonly referred to as NAVMACS II is a ship-to-ship or ship-to-shore-to-ship message processing system. NAVMACS II processes and records all incoming and outgoing message traffic and serves as an automated shipboard terminal for the Common User Digital Information Exchange System (CUDIXS). The NAVMACS system guards up to four Broadcast channels and automatically processes and prints a hard copy of any high precedence message requiring immediate response. The NAVMACS system architecture provides an RS-232 serial output capability for interfacing with other Local Area Networks (LANs), enabling NAVMACS II message traffic to be distributed to and received from terminals/workstations in various spaces throughout the ship. The NAVMACS sends and receives messages via the Fleet Satellite Communications (FLTSATCOM) system at 9600 kbs, or the High Frequency (HF) system at 9600 kbs Independent Side Band (ISB), 1200 kbs High Speed Fleet Broadcast (HSFB), or 2400 kbs HF digital links.

The Bridge To Bridge Communications System is a stand-alone, Very High Frequency (VHF), radio system comprised of a Transceiver, handset, speakers and a dedicated antenna which provides the capability for short-range, nonsecure, voice communications in the VHF range. The Bridge To Bridge Communications System is used primarily for communications between bridge personnel aboard units operating in close proximity to each other such as during underway replenishment.

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