Abstract: A wideband electronically scanned cylindrical array includes an array of end-fire radiating elements, the elements arranged in a first plurality of columns, the columns arranged radially about a center axis of the array. A beamforming network is connected to the array of radiating elements. The beamforming network includes a power divider circuit for dividing an input RF drive signal into a second plurality of drive signals, and a matrix of electronically controlled transfer switches. A true time delay network comprising a third plurality of delay lines couples respective ones of the drive signals to the matrix of transfer switches. A third plurality of transmit amplifiers is coupled to the matrix of transfer switches, each amplifier for amplifying a respective one of the drive signals. The beamforming network further includes apparatus for coupling the amplified drive signals to selected ones of the columns of radiating elements.

Abstract: A very wide-band or dual-band phased array antenna using stacked-disc radiators on stacked-dielectric cylindrical posts to form radiator elements. Each radiator element includes a ground plane, a lower dielectric cylindrical post of a high dielectric material adjacent the ground plane, a lower thin conductive radiator disc formed on the upper surface of the lower dielectric post, an upper dielectric cylindrical post of a low dielectric material disposed on top of the lower post and lower radiator disc, and an upper thin radiator disc or annular ring formed on the upper surface of the upper post. The first radiator disc is excited by two pairs of probes arranged in orthogonal locations. Each pair of probes can be fed by coaxial cables with 180 degree phase reversal. The second radiator disc or annular ring is a parasitic radiator without feeding probes. Depending on the feed arrangement, the radiator elements can achieve single-linear polarization, dual-linear polarization or circular polarization.

Abstract: An apparatus for testing a microwave phased array antenna having a plurality of radiating elements includes a transmission line for signal injection and switching components to selectively establish signal paths from a transmitter, and through a plurality of transmit/receive modules, to a performance monitor. In accordance with the present invention the switching components can be set to establish a receive signal path through the apparatus to test the receive mode of the individual modules. Alternatively, the switching components can be set to establish a transmit signal path through the apparatus to test the transmit mode of the individual modules. Further, the switching components can be set to selectively establish a receive signal path or a transmit signal path through either isolated individual modules or through all modules simultaneously.

Abstract: In a printed circuit embodiment, dielectric boards in a multilayer arrangement have their ends protruding from a ground plane. Sets of printed dipole elements are disposed along the edge of each board. Each set of dipole elements has three feed ports. Bandpass filters are provided for each feed port. Phase shifters are coupled to each of the feed ports through its respective bandpass filter. At the low band, the outer feed ports are shorted by the filters so that the two sections of dipole elements to the left of the center feed port form one lone band dipole arm, and the two sections of dipole elements to the right of the center feed port form the other low band dipole arm. The low band dipole is driven at the center feed port. At the high band, the center feed port becomes an open circuit so that the two sections to the left thereof form one high band dipole, and the two sections to the right thereof form a second high band dipole. The two outer feed ports drive the dipole array at the high band.

Abstract: An antenna for radiating electromagnetic power with plural octave bandwith is formed of an array of microstrip radiating elements each of which includes a microstrip conductor element spaced apart from a ground-plane element. A common ground-plane element is employed by all of the radiators in a row of the antenna, there being a plurality of the rows disposed parallel to each other. In each radiator, the microstrip conductor element is formed of an input section which is coupled to a feed, and an output section extending to an output end of the radiator for forming a radiating aperture of the radiator. In each output section, there is a two-dimensional enlargement of a cross-section of the radiator, one dimension of enlargement being parallel to the ground-plane element, and the other direction of enlargement being perpendicular to the ground-plane element. Enlargement in the direction parallel to the ground-plane element is accomplished by increasing the width of the conductor element.

Abstract: A dual band, phased array antenna especially adaptable for tactical radar capable of performing search, track and identification in a hostile jamming environment. The dual band array antenna is essentially two antennas sharing a common antenna aperture. The two antennas possess separate feed system and beam steering control. Thus, the beams for each frequency band can be steered independently and simultaneously. This design utilizes an ultra-wide band radiating element which can operate over approximately an octave bandwidth encompassing two adjacent microwave bands. In particular, the dual band signals can be received efficiently by the radiating element. A dual band coaxial-to-waveguide transition can be used to carry the signals to a diplexer. The dual band signals are separated at the diplexer and can be processed in separate feed networks.

Abstract: A dual band array antenna is disclosed having interleaved waveguide and dipole arrays, each operating in a different frequency band. The orientation of the waveguides and dipoles is such that polarization of the signals of the two frequency bands is perpendicular to each other, thus reducing mutual coupling. The waveguides are used for the higher frequency band and their cutoff frequency is selected to be above the lower frequency band at which the dipoles operate, in order to reduce mutual coupling into the waveguides. In one embodiment the dipoles are printed on a substrate having a dielectric constant selected so that dipole spacing is the same as the waveguide spacing. This eliminates grating lobe formation in the radiation pattern of the waveguide array. A low pass filter is included in the dipole feed circuit to reject the frequencies at which the waveguides operate.