Abstract: Embodiments of a wide band multi-polarization antenna system are described, which can be attached to the back or front of a soldier's vest or backpack. The antenna system can allow for release of pre-shaped integral radiating elements that spring into a geometric configuration suitable for circular polarization radiation or linear polarization over a desired band of frequencies. The antenna system can provide, when collapsed, linear polarized line-of sight capability over a wide band of frequencies. In a collapsed low-profile state, the antenna system can remain on the soldier, but out of the way for maneuvering.

Abstract: Embodiments of a wide band multi-polarization antenna system are described, which can be attached to the back or front of a soldier's vest or backpack. The antenna system can allow for release of pre-shaped integral radiating elements that spring into a geometric configuration suitable for circular polarization radiation or linear polarization over a desired band of frequencies. The antenna system can provide, when collapsed, linear polarized line-of sight capability over a wide band of frequencies. In a collapsed low-profile state, the antenna system can remain on the soldier, but out of the way for maneuvering.

Abstract: Embodiments of a wide band multi-polarization antenna system are described, which can be attached to the back or front of a soldier's vest or backpack. The antenna system can allow for release of pre-shaped integral radiating elements that spring into a geometric configuration suitable for circular polarization radiation or linear polarization over a desired band of frequencies. The antenna system can provide, when collapsed, linear polarized line-of sight capability over a wide band of frequencies. In a collapsed low-profile state, the antenna system can remain on the soldier, but out of the way for maneuvering.

Abstract: Embodiments of a wide band multi-polarization antenna system are described, which can be attached to the back or front of a soldier's vest or backpack. The antenna system can allow for release of pre-shaped integral radiating elements that spring into a geometric configuration suitable for circular polarization radiation or linear polarization over a desired band of frequencies. The antenna system can provide, when collapsed, linear polarized line-of sight capability over a wide band of frequencies. In a collapsed low-profile state, the antenna system can remain on the soldier, but out of the way for maneuvering.

Abstract: Embodiments of a wide band multi-polarization antenna system are described, which can be attached to the back or front of a soldier's vest or backpack. The antenna system can allow for release of pre-shaped integral radiating elements that spring into a geometric configuration suitable for circular polarization radiation or linear polarization over a desired band of frequencies. The antenna system can provide, when collapsed, linear polarized line-of sight capability over a wide band of frequencies. In a collapsed low-profile state, the antenna system can remain on the soldier, but out of the way for maneuvering.

Abstract: An antenna system for satellite communication, mounted on a moving platform, includes an antenna assembly, a control and display unit, and an antenna steering unit. The antenna assembly includes mounted on an antenna mast. The antenna steering unit includes a support housing, a rotary joint comprising a BNC connector, an electronic magnetic compass. an angular velocity-sensing gyroscope, a global positioning system receiver, a signal processor and a motor. The direction of the antenna's azimuth axis is determined based on the heading of the moving platform determined by the signal processor. In one embodiment, the director elements, the antenna mast and the azimuth mast are all articulated on flexible joints comprising a cable and spring mechanism allowing the director elements to fold toward the antenna mast and allowing the antenna assembly to fold toward the azimuth mast for stowing.

Abstract: A multiband antenna includes one or more first antennas embedded within a second antenna. The one or more first antennas can include a folded dipole, and the second antenna can include a monopole. The folded dipole and the monopole may operate at different resonant frequencies. Because the folded dipole is embedded in the monopole, rather than being a separate antenna, near-field coupling between the antennas may be reduced, resulting in enhanced radiation patterns by one or both antennas. More complex antenna structures can also be constructed having multiple antennas embedded within one or more antennas.

Abstract: An antenna system for satellite communication, mounted on a moving platform, includes an antenna assembly, a control and display unit, and an antenna steering unit. The antenna assembly includes a dipole driven element assembly and at least one director element mounted on an antenna mast. The antenna steering unit includes a support housing, a rotary joint comprising a BNC connector, an electronic magnetic compass. an angular velocity-sensing gyroscope, a global positioning system receiver, a signal processor and a motor. The direction of the antenna's azimuth axis is determined based on the heading of the moving platform determined by the signal processor. In one embodiment, the director elements, the antenna mast and the azimuth mast are all articulated on flexible joints comprising a cable and spring mechanism allowing the director elements to fold toward the antenna mast and allowing the antenna assembly to fold toward the azimuth mast for stowing.

Abstract: A system for computing a pattern function for a polygonal pattern having a finite number of predetermined face angles. One method includes the steps of decomposing the polygon into a set of flashes, computing the pattern function by summing together all flashes evaluated at a point (x,y), and the pattern function returning a 1 if point (x,y) is inside a polygon and otherwise will return a 0.

Abstract: A phase-locked-loop-stabilized voltage controlled oscillator relies on a sampling of the analog-frequency-control voltage of a voltage-controlled oscillator in a phase-locked-loop circuit to act as a reference voltage for a second free-running voltage-controlled oscillator. A vernier-adjustment voltage is injected into the control input of the second voltage-controlled oscillator to produce a finely variable derivative frequency not otherwise producible by a conventional phase-locked-loop circuit.

Abstract: A layout versus schematic (LVS) comparison tool determines one-to-one equivalency between an integrated circuit schematic and an integrated circuit layout by performing operations to generate color symmetrizing matrices corresponding to respective child cells in the integrated circuit schematic. Here, the child cells are characterized as having a number of symmetrical configurations which at a port level are electrically equivalent. Operations are also performed to generate a first color symmetry vector for a child cell in the integrated circuit schematic and a second color symmetry vector for the corresponding child cell in the integrated circuit layout. A vector equivalency is also preferably determined by comparing a product of the color symmetrizing matrix and the first color symmetry vector against a product of the color symmetrizing matrix and the second color symmetry vector.

Abstract: The present invention includes a method for automatically reconstructing most of the power, ground and clock prerouting without significant user involvement. This enables several floorplans to be tried concurrently in a batch mode. The method automatically migrates many floorplans in increments to find the best result for each starting floorplan. The user is then free to select a floorplan that looks best from the candidates generated with all the special net routing patterns already considered and updated for each.

Abstract: A method, apparatus and computer program product performs a bounded parasitic extraction of typically all nets in an integrated circuit as part of a series of post-layout verification operations. According to one embodiment, a resistance-only extraction and/or a capacitance-only extraction is initially performed using computationally inexpensive electrical models of the nets. The resistance and capacitance extractions may be combined with models of the active devices to generate realistic worst case and best case delay models for each of the extracted nets. The delay models may be based on the resistance-only extraction and an upper bound on the parasitic capacitance of the net determined from the capacitance-only extraction, however, other models based solely on a resistance-only extraction may also be used, although they are typically less preferred.

Abstract: In a computer system, a method for an area based place and route of an integrated circuit layout that provides automatic iterative area placement of module cells intelligently and effectively. In one embodiment, this is accomplished in three phases. The searching phase determines which hot spot is to be refined based on a congestion map. Next, the refining phase chooses a box with the proper aspect ratio, cut line direction, and placement options for minimizing the hot spot. The scheduling phase then decides whether to proceed with another area placement based on the current result or to restore a previous placement that exhibited superior characteristics. In the course of the area placements, several parameters are randomly varied in an intelligent manner so that successive iterative area placements produce equivalent or better results. All of this is accomplished without human intervention or expert knowledge. Instead, the computer system continuously runs its program until a design goal is attained.

Abstract: A method for optimal track assignment in a grid-based channel router. Initially, interconnection information is extracted from a global routing result. Multiple pin nets derived from the interconnection information are decomposed into simpler mapped segments. A channel grid map is then built and marked with existing objects. Next, a vertical constraint graph specifying the relative positions of the mapped segments is constructed. A first track is computed. A track assignment loop is repeated until all requisite connections are realized. The track assignment loop includes the steps of breaking cycles and long paths and collecting a set of feasible links. One or more weighting functions are assigned to each such feasible link. A dynamic programming approach is used to select an optimal set of feasible links according to the weighting functions. In addition, an optimal set of feasible links corresponding to unpreferred layers is collected by applying dynamic programming.

Abstract: Hierarchical look-ahead congestion-driven placement is a look-ahead method for avoiding interconnect congestion. It balances the available routing resources. When incorporated into conventional quadratic programming approaches, only minor increases in run-time are needed to produce dramatic decreases in congestion. The macrocell densities are traded between adjacent regions to anticipate congestion, and are estimated based on the current iteration for the distribution of cells and net connections involved. The congestion estimation also takes routing detour due to the presence of large hard macros into account for accuracy. The macrocell density adjustments are propagated to all the neighboring regions at each hierarchical level to revise the prior congestion estimate from the previous hierarchical iteration.

Abstract: In a grid-based channel router, a method for handling variable width wires. The user initially specifies the widths of the wires. In this manner, wider wires may be selected for special nets, such as those used for routing clock signals, whereas narrower wires are used for normal nets in order to minimize the die size. A refined grid map is generated. This refined grid map consists of extra rows and columns for marking the variable width wires. These extra rows and columns are spaced as a function of the wire width and are marked the same as with normal rows and columns. Before a wire is placed, the affected rows or columns are checked for any violations. If there are no violations, the wire is placed and the appropriate rows or columns are marked. Due to the extra rows and columns, the problems associated with overmarking and undermarking variable width wires are avoided.