Page:Electronics Technician - Volume 7 - Antennas and Wave Propagation - NAVEDTRA 14092.pdf/42

 Figure 2-33.—0E-82AIWSC-1(V)/ANIWSC-5(V) Shore station antenna.

the antenna weighs 2500 pounds and is 15 feet high,10 feet wide, and 10 feet deep. The gain characteristics of this antenna are nominally 15 dB in transmit and 18 dB in receive.

ANDREW 58622 SHORE ANTENNA

The Andrew 5 8622 antenna (fig. 2-34) is a bifilar, 16-turn helical antenna, right-hand circularly polarized, with gain varying between 11.2 and 13.2 dB in the 240-315 MHZ frequency band. It has a 39-inch ground plate and is about 9 feet, 7 inches long. It can be adjusted manually in azimuth and elevation. This antenna is used at various shore installations, other than NCTAMS, for transmit and receive operations.

AN/WSC-6(V) SI-IF SATCOM ANTENNA

The antennas used on current shf SATCOM shipboard terminals are parabolic reflectors with cassegrain feeds. These antennas provide for LPI (low probability of intercept), with beamwidths less

Figure 2-34.-Andrew 58622 shone antenna.

Figure 2-35.—ANIWSC-6(V) attenuation scale.

than 2.5 degrees (fig. 2-35). The reflectors are mounted on three-axis pedestals and provide autotracking of a beacon or communication signal by conical scanning techniques. The antennas are radome enclosed and include various electronic components. Both a 7-foot model (fig. 2-36) and a 4-foot model (fig. 2-37) are operational in the fleet. 2-20