Abstract: A phased array antenna system with intermodulation beam nulling device includes nulling phase shifters.

Abstract: System and method for detecting a smooth/rough boundary from an aerial image to solve the problem of isolating image features without access to the subject of the image. The system and method convert the image to gray scale, edge pad the converted image, calculate an image entropy based on a distribution of local entropy across the padded, converted image, threshold the image entropy to binarize the padded, converted image, clean noise, and close defects and voids by mathematical morphologically opening and closing the binarized image, and detect the smooth/rough boundary of the opened/closed binarized image as a gradient across the pixels of the opened/closed binarized image resulting in a single pixel width edge. The single pixel width edge can be, for example, provided to numerical prediction models and computer games.

Abstract: An antenna system includes a heptagonal antenna array having one center antenna element and seven circumferentially surrounding antenna elements offering improved near and far sidelobe rejection, which is well suited for mechanically-gimbaled and time delayed electrical steering antenna applications.

Abstract: A phased array antenna system with intermodulation beam nulling device includes nulling phase shifters.

Abstract: An antenna system includes a heptagonal antenna array having one center antenna element and seven circumferentially surrounding antenna elements offering improved near and far sidelobe rejection, which is well suited for mechanically-gimbaled and time delayed electrical steering antenna applications.

Abstract: An antenna system includes a heptagonal antenna array having one center antenna element and seven circumferentially surrounding antenna elements offering improved near and far sidelobe rejection, which is well suited for mechanically-gimbaled and time delayed electrical steering antenna applications.

Abstract: A transmission line junction for a coaxial conductor line has mating ends of interfitting cores, sleeves, and dielectrics for communicating broadband signals through the junction that blocks DC currents and voltages, the junction maintaining a quarter wavelength junction length for high frequency coupling while providing improved low frequency coupling across the junction.

Abstract: A receiving system includes a combiner configured to receive signals from two or more antenna elements and to generate sum and difference outputs, and a switch configured to sequentially provide the sum and difference outputs as inputs to a receiver.

Abstract: A transmission line junction for a coaxial conductor line has mating ends of interfitting cores, sleeves, and dielectrics for communicating broadband signals through the junction that blocks DC currents and voltages, the junction maintaining a quarter wavelength junction length for high frequency coupling while providing improved low frequency coupling across the junction.

Abstract: An antenna system includes a heptagonal antenna array having one center antenna element and seven circumferentially surrounding antenna elements offering improved near and far sidelobe rejection, which is well suited for mechanically-gimbaled and time delayed electrical steering antenna applications.

Abstract: A method for reducing intermodulation beams includes applying a beam-smearing phase distribution in addition to a beam-steering distribution for scanning to an array of antenna elements such that multiple higher-order intermodulation products are simultaneously reduced.

Abstract: A phased array antenna system divides the array into a plurality of subarrays that are driven by fine phase shifters with each subarray having a plurality of antenna elements driven by respective coarse phase shifters that are preferably MEMS coarse phase shifters having low weight and low cost and are infrequently used for improved reliability for selecting a coarse beam coverage area while the fine phase shifters are used to scan a high-gain antenna pattern within the selected coarse beam coverage area. Two-bit MEMS phase shifters are used to scan the beams from subarrays to various coverage areas within the required antenna field of view, thereby providing coarse beam steering for an array.

Abstract: A symmetric N×N branch-line hybrid power divider/combiner has N input ports and N output ports. The divider/combiner divides received powers at each input port and transmits and combines the divided powers to the output ports. The divider/combiner includes N through transmission lines, each coupling a respective input port to a respective output port. The divider/combiner also includes N input branch transmission lines, each coupling a respective input port to a central input node and N output branch transmission lines, each coupling a respective output port to a central output node.

Abstract: A symmetric N×N branch-line hybrid power divider/combiner has N input ports and N output ports. The divider/combiner divides received powers at each input port and transmits and combines the divided powers to the output ports. The divider/combiner includes N through transmission lines, each coupling a respective input port to a respective output port. The divider/combiner also includes N input branch transmission lines, each coupling a respective input port to a central input node and N output branch transmission lines, each coupling a respective output port to a central output node.

Abstract: A power divider/combiner for dividing received powers at 4 input ports, transmitting the divided powers to each of 4 output ports and combining the transmitted powers at each of the output ports. The power divider combiner has through transmission lines flanked on either side by secondary through transmission lines that interconnect corresponding input and output ports. The through transmission lines are likewise interconnected at a center node by a plurality of branch transmission lines. A method for making a power divider/combiner includes merging two 0 dB couplers by joining the center points of each of the branch transmission lines.

Abstract: A reflectarray antenna for achieving increased dynamic phase range has a plurality of dipole elements positioned across the antenna surface. The elements include a single dipole element having a predetermined length that is approximately proportional to the dynamic phase range through which the first dipole element can reflect. The elements also include a coupled dipole element which comprises a longer dipole and a shorter dipole. The longer dipole and the shorter dipole are positioned on the reflectarray surface such that they are spaced a predetermined distance apart.

Abstract: Microwave power divider/combiners are provided which divide received powers at each of 2.sup.n input ports transmit the divided powers to each of 2.sup.n output ports and combine the transmitted powers at each of the output ports. They have through transmission lines which each couple respective pairs of the input and output ports. In addition, they include shunt transmission lines, an input network of transmission lines which couples the input ports to first ends of the shunt transmission lines and an output network of transmission lines which couples second ends of the shunt transmission lines to the output ports to thereby provide transmission paths from each of the input ports to each of the output ports. The input and output transmission-line networks are configured to be identical and to cause the power divider/combiner to have interport symmetry between the input and output ports and intraport symmetry between any equal sets of input and output ports.