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MIL-HDBK-412
SITE SURVEY AND FACILITY DESIGN HANDBOOK FOR SATELLITE EARTH STATIONS
Year: 1981
Abstract: The purpose of this handbook is to provide general technical information pertaining to facility engineering of satellite earth stations, both fixed and vanized, and to serve as a guide to more detailed information contained in referenced engineering and planning publications.
This handbook presents selected topics in earth station facility engineering to telecommunications engineers, managers, and senior operations and maintenance (O&M) personnel. These topics cover the site selection process and the design of site facilities (including physical structures and the electrical power and ground systems). Although this handbook applies mainly to medium and heavy earth stations, portions may be used for siting tactical or special-use terminals. The term "vanized equipment," as used here, applies both to Defense Communications System (DCS) equipment that is mounted in vans and to tactical equipment that is mounted in vans or shelters. The discussion of site selection information is augmented by the inclusion of sample worksheets (appendix A) as information collection aids.
The satellite communication system has a number of advantages that makes it attractive as either a replacement for, or a backup to, present terrestrial systems. These advantages include increased channel capacity, relative terrain independence, and (under some conditions) higher resistance to jamming efforts. Satellite communications will continue to expand as a burgeoning technology provides advances in modulation techniques and frequency utilization. With these advances, satellite networks will readily lend themselves to the Defense Communications Agency (DCA) plan for increased use of digital communications. The systems engineering objectives for earth stations in the Defense Satellite Communications System (DSCS) will emphasize sustaining and improving survivability, durability, security, and interoperability. Terminal interconnectivity structure is expected to shift from the present configurations of terrestrial backbone transmission and switching networks to direct access via satellite.
The earth station (ES) is the total DSCS facility from the interconnect facility (ICF) circuit connections at the patch and test facility (PTF) of the servicing technical control facility (TCF) to the satellite radio frequency (rf) patch at the antenna of the ES. The ES includes the ICF, the communications subsystem (CSS), the rf generation and frequency conversion, tracking and antenna equipment, monitoring and control facilities, and the site power generation and distribution. Earth stations presently deployed in the DSCS, stage 1-C, have four basic configurations, as shown in figure 1 and described in the following paragraphs. Differences among the configurations involve the interconnect technique and the relative locations of the earth station, TCF, and CSS.
The earth station, including all the CSS equipment, is connected to the nearby TCF by multiple baseband cables or optical fiber bundles.![FIGURE 1. Basic earth station configurations.]()
The earth station is linked to the distant TCF by microwave radio. In this configuration, the CSS equipment is split up, with the modems located in the earth station, and the multiplex and line-conditioning equipment located in the TCF.
The earth station and the TCF are in the same building with the TCF, and interconnected with the CSS by cables.
The earth station and the TCF are in nearby separate buildings and are interconnected by cable. The CSS is also split up in this configuration, as described in configuration II above.
A satellite earth station employed in a non-nodal capacity forms only a single link with another station; it has no relay capability. A satellite earth station employed in a nodal capacity is characterized by two or more antennas and may serve as a relay in multiple links of a network.
Safety considerations within the scope of this handbook are: (1) potential radiation hazards presented to ordinance, fuel, and personnel in, the vicinity of the earth station antenna(s) and (2) electric shock hazards encountered in power panels and other high-voltage areas on the site. Lightning protection and fault protection subsystems, providing protection for both personnel and equipment, will be considered.
MIL-HDBK-238 and AFOSH 161-9 prescribe energy density level limits for the protection of personnel. Hazard standards for fuels and various electroexplosive ordinance devices are prescribed by the individual services, such as in T.O. 31Z10-4 and AFM 127-100. All three military services maintain agencies responsible for conducting radiation-level surveys at operational and proposed sites (see DARCOM-P-706-410).
Protection against shock hazards is best assured by proper ac wiring, bonding, and grounding practices (including lightning and fault protection subsystems and earth electrode subsystems).
At all earth stations, frequencies to be used must coordinated in accordance with the procedures of the service in charge.
This handbook presents selected topics in earth station facility engineering to telecommunications engineers, managers, and senior operations and maintenance (O&M) personnel. These topics cover the site selection process and the design of site facilities (including physical structures and the electrical power and ground systems). Although this handbook applies mainly to medium and heavy earth stations, portions may be used for siting tactical or special-use terminals. The term "vanized equipment," as used here, applies both to Defense Communications System (DCS) equipment that is mounted in vans and to tactical equipment that is mounted in vans or shelters. The discussion of site selection information is augmented by the inclusion of sample worksheets (appendix A) as information collection aids.
The satellite communication system has a number of advantages that makes it attractive as either a replacement for, or a backup to, present terrestrial systems. These advantages include increased channel capacity, relative terrain independence, and (under some conditions) higher resistance to jamming efforts. Satellite communications will continue to expand as a burgeoning technology provides advances in modulation techniques and frequency utilization. With these advances, satellite networks will readily lend themselves to the Defense Communications Agency (DCA) plan for increased use of digital communications. The systems engineering objectives for earth stations in the Defense Satellite Communications System (DSCS) will emphasize sustaining and improving survivability, durability, security, and interoperability. Terminal interconnectivity structure is expected to shift from the present configurations of terrestrial backbone transmission and switching networks to direct access via satellite.
The earth station (ES) is the total DSCS facility from the interconnect facility (ICF) circuit connections at the patch and test facility (PTF) of the servicing technical control facility (TCF) to the satellite radio frequency (rf) patch at the antenna of the ES. The ES includes the ICF, the communications subsystem (CSS), the rf generation and frequency conversion, tracking and antenna equipment, monitoring and control facilities, and the site power generation and distribution. Earth stations presently deployed in the DSCS, stage 1-C, have four basic configurations, as shown in figure 1 and described in the following paragraphs. Differences among the configurations involve the interconnect technique and the relative locations of the earth station, TCF, and CSS.
The earth station, including all the CSS equipment, is connected to the nearby TCF by multiple baseband cables or optical fiber bundles.
The earth station is linked to the distant TCF by microwave radio. In this configuration, the CSS equipment is split up, with the modems located in the earth station, and the multiplex and line-conditioning equipment located in the TCF.
The earth station and the TCF are in the same building with the TCF, and interconnected with the CSS by cables.
The earth station and the TCF are in nearby separate buildings and are interconnected by cable. The CSS is also split up in this configuration, as described in configuration II above.
A satellite earth station employed in a non-nodal capacity forms only a single link with another station; it has no relay capability. A satellite earth station employed in a nodal capacity is characterized by two or more antennas and may serve as a relay in multiple links of a network.
Safety considerations within the scope of this handbook are: (1) potential radiation hazards presented to ordinance, fuel, and personnel in, the vicinity of the earth station antenna(s) and (2) electric shock hazards encountered in power panels and other high-voltage areas on the site. Lightning protection and fault protection subsystems, providing protection for both personnel and equipment, will be considered.
MIL-HDBK-238 and AFOSH 161-9 prescribe energy density level limits for the protection of personnel. Hazard standards for fuels and various electroexplosive ordinance devices are prescribed by the individual services, such as in T.O. 31Z10-4 and AFM 127-100. All three military services maintain agencies responsible for conducting radiation-level surveys at operational and proposed sites (see DARCOM-P-706-410).
Protection against shock hazards is best assured by proper ac wiring, bonding, and grounding practices (including lightning and fault protection subsystems and earth electrode subsystems).
At all earth stations, frequencies to be used must coordinated in accordance with the procedures of the service in charge.
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