An analyzer device for VOR navigational receivers utilizes a first receiver section in which the reference phase, transmitted in the form of a frequency modulation, is available in demodulated form as reference signal, and a second receiver section in which the rotational phase, depending upon the particular direction of the antenna pattern, occurs in the form of an amplitude modulated rotating signal. Angular information in the azimuthal plane is obtained from a comparison of the reference phas...

The radio navigation apparatus disclosed herein facilitates perception by the pilot of an aircraft of passage through the intersection of preselected bearings relative to selected radio beacons. Deviation from one of the bearings is indicated on a first indicator having a pointer which swings laterally to indicate course deviation in conventional manner while departure from the second bearing is indicated on an indicator having a pointer which swings vertically and which crosses the pointer of t...

A capture effect antenna system in which the course and clearance signals are transmitted from a single antenna array. The clearance carrier signal has a substantial null along the course centerline, to thereby cause significant reduction in the course bends.

Transmitter apparatus for glide path guidance includes two aerials spaced apart (preferably so that the perpendicular bisector of a line joining the aerials is parallel to the desired glide path) and means for feeling them with distinct but related frequency-modulated waveforms so as to yield at least two distinguishable cross-correlation products whose relative amplitudes will vary differentially with displacements from the desired glide path. One aerial may be fed with a first carrier frequenc...

A transmission device of a radiographic navigation system for azimuth determination, in which an electronic rotating directional beam pattern and a static omnidirectional phase reference beam pattern are generated. For obtaining exact phase relationships between the signals required for generating the said beam patterns, phase control loops are included in the signal paths; in these loops the carrier wave frequencies are transposed to a lower frequency and the modulations are removed before phas...

A two-frequency capture-effect instrument landing system employs a single localizer antenna array for both course-frequency and clearance-frequency radiation. The composite course and clearance signals are formed by networks that utilize trees of hybrid power dividers to effect unequal power division and distribute the signals to the antenna feeders. Integral monitoring is provided by similar networks, operating backwards in a functional sense, which recombine samples of the RF energy on the ant...

A microwave detector includes a horn antenna and cavity formed by covering a metallic film of a printed substrate with an opened bottom microwave circuit component, and further includes a mixer diode which is positioned at the feeding point of the horn antenna and sandwiched between the microwave circuit component and the printed substrate, the mixer diode including a mixer diode substrate having a first protruding portion at a first end of the mixer diode substrate and a second protruding porti...

Precision guidance of aircraft throughout a great volume of positions, and with spectrum economy, is achieved with coordinated scanning of coarse and fine coverage localizer antennas and coarse and fine glide-path antennas. The scan coordination is predetermined for sequential traversals of the useful scan sectors, microwave transmission through the several antennas being effected in the sequence of the scans. Each such transmission includes modulation not only in accordance with the antenna sca...

An improved glide slope receiver circuit prevents false acquisition of glide slope and insures that only a good and existing glide slope signal will arm the glide slope circuitry. A normally charged capacitor applies lock-out potential to the glide slope switching network. A reference square wave is applied to open a gate. Below glide slope signals are received out of phase with the reference and proceed through the gate to discharge the capacitor through a time constant network. Discharge of th...

A localizer signalling system for guiding a craft along a course defined by double lobe course and clearance radiation patterns of different frequencies has a single array of radiating elements all energized by a "Course" group of frequencies and some or all elements energized by a "Clearance" group of frequencies through directional couplers, the coupling factor of the directional couplers determining the ratio of course frequency power to clearance frequency power energizing the array.