Broadband Antennas

Figure 2-28.—AS-2815/SSR-1 antenna physical configuration. Figure 2-26. This antenna is normally mounted horizontally. BROADBAND ANTENNAS Broadband antennas for HF and UHF bands have been developed for use with antenna multicouplers. Therefore, several circuits may be operated with a single atenna. Broadband antennas must be able to transmit or receive over a wide frequency band. HF broadband antennas include the 35-foot twin and trussed whips, half-cone, cage, and a variety of fan- designed antennas. The AT-150/SRC UHF antenna in figure 2-26 is an example of a broadband antenna. SATCOMM ANTENNAS The antennas shown in figures 2-27 and 2-28 are used for satellite communications. The 0E-82C/WSC- 1(V) antenna (figure 2-27) is used with the AN/WSC-3 transceiver and designed primarily for shipboard installation. Depending upon requirements, one or two antennas may be installed to provide a view of the satellite at all times. The antenna is attached to a pedestal. This permits the antenna to rotate so that it is always in view of the satellite. The frequency band for receiving is 248 to 272 MHz and for transmitting is 292 to 312 MHz. The AN/SRR-1 receiver system consists of up to four AS-2815/SSR-1 antennas (figure 2-28) with an amplifier-converter AM-6534/SSR-1 for each antenna. The antennas are used to receive satellite fleet broadcasts at frequencies of 240 to 315 MHz. The antenna and converters are mounted above deck so that at least one antenna is always in view of the satellite. The newer satellite systems use the SHF band. One of the major advantages of these systems is that they use a very small parabolic antenna measuring only 12 inches in diameter. A satellite antenna must be pointed at the satellite to communicate. We must first determine the azimuth (AZ) and elevation (EL) angles from a fixed location. Figure 2-29 illustrates how these angles are derived, Figure 2-29.—Equatorial Satellite Antenna Pointing Guide. 2-23