scope:

This specification defines the requirements for two types of ILS localizer antenna arrays, each comprised of a given number of traveling wave localizer antennas, also defined herein. One type of array is for use at locations relatively free from reflection interference sources in the 180° front course azimuth sector of the array; the second type is for use at locations having a moderate extent of these interference sources in the front course sector. Both types of arrays are driven by two separate input signals, a modulated carrier signal and a carrier suppressed double sideband signal, obtained from conventional localizer transmitting equipment operating in the frequency band of 108 to 112 MHz. An integral monitor network is also included in both types of arrays.