摘要:
According to one embodiment, a circuit board comprises an anisotropic film disposed outwardly from a first flexible dielectric layer, and a second flexible dielectric layer disposed outwardly from the anisotropic film. The first and second flexible dielectric layers each have at least one conductive trace conductively coupled to a pad. The anisotropic film forms a via region that conductively couples the pad of the first flexible dielectric layer to the pad of the second flexible dielectric layer, and electrically isolates the conductive trace of the first flexible dielectric layer from the conductive trace of the second flexible dielectric layer.
摘要:
A phased array antenna adapted to be mounted in a helmet. In the illustrative embodiment, the antenna comprises a substrate and an array of radiating elements disposed on said substrate, each of the elements including a-resonant cavity and a mechanism for feeding the cavity with an electromagnetic signal., The cavity is formed in a multi-layer structure between a ground plane and a layer of metallization. A radiating slot or slots are provided in the layer of metallization. A first layer of dielectric material is disposed within the cavity. The feed mechanism is a microstrip feed disposed in the first layer of dielectric material parallel to a plane of a portion of the substrate over which an associated element is disposed. A layer of foam is disposed between the layer of dielectric material and the ground plane. Second and third parallel layers of dielectric material are included in each element. The second layer is disposed adjacent to the ground plane. A layer of element interconnection circuitry is disposed between the second and third layers of dielectric material. A transmit/receive module or circuitry for each element is secured to the third layer of dielectric material. The substrate may be conformal or conformable, as well as rigid. An arrangement is included for steering a beam transmitted or received by the antenna.
摘要:
A phased array antenna adapted to be mounted in a helmet. In the illustrative embodiment, the antenna comprises a substrate and an array of radiating elements disposed on said substrate, each of the elements including a-resonant cavity and a mechanism for feeding the cavity with an electromagnetic signal., The cavity is formed in a multi-layer structure between a ground plane and a layer of metallization. A radiating slot or slots are provided in the layer of metallization. A first layer of dielectric material is disposed within the cavity. The feed mechanism is a microstrip feed disposed in the first layer of dielectric material parallel to a plane of a portion of the substrate over which an associated element is disposed. A layer of foam is disposed between the layer of dielectric material and the ground plane. Second and third parallel layers of dielectric material are included in each element. The second layer is disposed adjacent to the ground plane. A layer of element interconnection circuitry is disposed between the second and third layers of dielectric material. A transmit/receive module or circuitry for each element is secured to the third layer of dielectric material. The substrate may be conformal or conformable, as well as rigid. An arrangement is included for steering a beam transmitted or received by the antenna.
摘要:
A partitioned aperture array antenna. The novel antenna includes a first subarray having a first number of antenna elements equipped with transmit functionality and a second subarray having a second number of antenna elements equipped with receive functionality, wherein the first and second numbers are not equal and the first and second subarrays have at least one common antenna element. In an illustrative embodiment, the first subarray includes a transmit circuit coupled to each antenna element in the first subarray for controlling a relative transmit phase of the antenna element to steer an overall antenna transmit beam, and the second subarray includes a receive circuit coupled to each antenna element in the second subarray for controlling a relative receive phase of the antenna element to steer an overall antenna receive beam.
摘要:
In one embodiment, a system for controlling the direction of an antenna beam includes a location identifier, an orientation sensor, and an antenna beam controller. The location identifier determines a transmit antenna location indicating the location of a transmit antenna, where the transmit antenna produces an antenna beam. The orientation sensor determines a transmit antenna orientation indicating the orientation of the transmit antenna. The antenna beam: accesses target data describing a receive antenna of a target, the target data comprising a location of the receive antenna relative to the transmit antenna; calculates a deviation value from the transmit antenna location, the transmit antenna orientation, and the target data; and adjusts the direction of the antenna beam to reduce the deviation value
摘要:
A situation awareness viewing device, typically in the form of a head-mounted display device, includes a polarizing beam splitter made of a cube of a material transparent to light and having an index of refraction greater than 1, and a wire grid polarizer lying within the cube on a cube-diagonal plane extending between two diagonally opposed edges of the cube. The polarizing beam splitter has a first optical axis extending from a first face of the cube toward an opposing second face of the cube and lying at an angle of 45 degrees to the cube-diagonal plane, and a second optical axis extending from a third face of the cube toward an opposing fourth face of the cube and lying at an angle of 45 degrees to the cube-diagonal plane, the second optical axis being perpendicular to the first optical axis. The device further includes an external polarizer external to the cube on the first optical axis and disposed to intercept light incident upon the first face along the first optical axis, an image source external to the cube and disposed to send a display image incident upon the third face along the second optical axis, a quarter-wave plate external to the cube and disposed to intercept a beam of light traveling along the second optical axis and passing out of the cube through the fourth face, and a mirror external to the cube and disposed to reflect light passing through the quarter-wave plate back through the quarter-wave plate and to the fourth face.
摘要:
Laser excitation is generally initiated by "dumping" energy from a stored supply into a flashlamp. The flashlamp produces light which is a mixture of both black-body type radiation and atomic line spectra. That portion of the flashlamp output energy spectrum which overlaps the pump bands of Nd.sup.3.sup.+ causes the inversion population necessary for laser action. It has been determined that the sequence in which energy is initially supplied to the flashlamp is an important parameter. More particularly, light output in the pump bands, and hence laser efficiency, is increased by slightly turning on the flashlamp at a predetermined interval of time prior to the main energy dump. Theory indicates that this method of triggering results in a larger ionic path diameter at the time of main energy release to the flashlamp.
摘要:
An electronically scanned array antenna. The novel antenna includes a first planar array of antenna elements and one or more side planar arrays of antenna elements, each side array adjacent to the first array and tilted at a predetermined angle relative to the first array. In an illustrative embodiment, the antenna also includes a plurality of transmit/receive modules, each module coupled to one antenna element. Each transmit/receive module includes phase shifters for varying the relative phases of the antenna elements to form a desired overall beam pattern, and a low noise amplifier and high power amplifier for amplifying signals received and transmitted by the antenna element, respectively. In an illustrative embodiment, a processor provides individual phase and channel enable control signals for independently controlling the phase shifters and amplifiers, respectively, of each module.
摘要:
A partitioned aperture array antenna. The novel antenna includes a first subarray having a first number of antenna elements equipped with transmit functionality and a second subarray having a second number of antenna elements equipped with receive functionality, wherein the first and second numbers are not equal and the first and second subarrays have at least one common antenna element. In an illustrative embodiment, the first subarray includes a transmit circuit coupled to each antenna element in the first subarray for controlling a relative transmit phase of the antenna element to steer an overall antenna transmit beam, and the second subarray includes a receive circuit coupled to each antenna element in the second subarray for controlling a relative receive phase of the antenna element to steer an overall antenna receive beam.