摘要:
The present invention provides a radome for an endfire antenna array that includes a honeycomb core, an inner skin attached to the honeycomb core, a first set of conductive slats disposed on the inner skin of the honeycomb core and a second set of conductive slats that are disposed within the honeycomb core. The two sets of conductive slats are capacitively-coupled to one another.
摘要:
The present invention provides a radome for an endfire antenna array that includes a honeycomb core, an inner skin attached to the honeycomb core, a first set of conductive slats disposed on the inner skin of the honeycomb core and a second set of conductive slats that are disposed within the honeycomb core. The two sets of conductive slats are capacitively-coupled to one another.
摘要:
An array of dual trough radiator elements including orthogonally crossed trough waveguide cavities and RF feed members of predetermined adjustable length extending across the cavities from one radiator element to its neighbor, where the feed members are suspended in a slot formed in the body radiator elements and where the inner or proximal ends are connectable to an RF energy source while the outer or distal end is unconnected in an open circuit arrangement. The array also includes intermediate support members of electrical insulation located on an outer surface of the radiator element and a switchable parasitic ground plane consisting of a set of parasitic conductor elements is located on a top surface of the intermediate support member.
摘要:
An antenna element for radiating electromagnetic signals having a first and a second generally C-shaped groundplane that are formed of conductive material. The groundplanes are connected to one another and define a notch which has one end that is open to free space. An elongated section of transmission line is disposed between the two groundplanes. The transmission line has a source receiving end connectable to a signal source and also has a feed end opposite to the source receiving end. A segment which acts as a transformer is located within the notch. The transformer segment has a first end that is connectable to the feed end of the transmission line and has a second end which faces the notch open end.Preferably, at least one transformer step is located along the transmission line between the source receiving end and the feed end. Also, an open circuit section of transmission line is preferably connected to the transformer segment second end.
摘要:
Apparatus which overcomes the blockage effect of an object in the path of a beam of RF energy, includes a conformal array of parasitic electrical conductor elements having a length of about .lambda./3 and which are selectively located above the surface of the object, also at a height of about .lambda./3. The parasitic conductor elements operate to duct the RF energy of the beam around the object with minimal loss in gain and effect on the beam's radiation pattern.
摘要:
A radar antenna system, adapted to be supported on an aircraft for surveillance, employs a nonconducting disk radome structured with aerodynamic fairing and otherwise to produce relatively low aerodynamic drag. A plurality of struts are used to secure the disk radome to the aircraft with the disk radome generally extending in a solid horizontal reference plane. A plurality of elongated, relatively low gain radiating elements are supported by a ground-plane box within the disk radome, with the radiating elements distributed across the disk radome and disposed to radiate generally in the vertical direction. An electronic system is supported within the ground-plane box, and it includes respective transmit/receive circuits which send and receive radio frequency signals to and from the radiating elements. Power cables extend through the struts to couple signals between the electronic system in the disk radome and radar system level circuitry located externally of the disk radome.
摘要:
A nonsquinting end-fed quadrifilar helical antenna is provided. Each conductor of the antenna is fed with a successively delayed phase representation of the input signal to optimize transmission characteristics. Each of the conductors is separated into a number Z of discrete conductor portions by Z-1 capacitive discontinuities. The addition of the capacitive discontinuities results in the formation of an antenna array. The end result of the antenna array is a quadrifilar helical antenna which is nonsquinting (radiates in a given direction independently of frequency).
摘要:
A negative slope phase skewer for use between radiating elements of series fed antenna array. The phase skewer has a four part coupler having two segments lying parallel to one another, each segment being a near and a far branch. The two near branches connect to the transmission line, while the far branches are at some distance from the transmission line. A series of spaced apart, progressively longer, high impedance open circuited stubs extends outward perpendicularly from each far branch. Two conductive connections connect the two segments between the transmission line and the stubs. Each stub is designed to be one quarter wavelength long of an average frequency in a band region of an operating band width, and are spaced apart by a quarter wavelength of the midpoint of the operating band.