摘要:
A phase shifter comprises a substrate, a ground plane formed on a first surface of the substrate, a support structure positioned on a second surface of the substrate opposite the first surface, three parallel, non-co-planar microstrip lines supported by the support structure above the second surface of the substrate, a ferrite element supported by the support structure between the second surface of the substrate and the three non-co-planar microstrip lines, and means for applying a magnetic field to the ferrite element.
摘要:
A space-fed conformal array for a high altitude airship includes a primary array lens assembly adapted for conformal mounting to a non-planar airship surface. The lens assembly includes a first set of radiator elements and a second set of radiator elements, the first set and the second set spaced apart by a spacing distance. The first set of radiators faces outwardly from the airship surface to provide a radiating aperture. The second set of radiators faces inwardly toward an inner space of the airship, for illumination by a feed array spaced from the second set of radiators.
摘要:
A conformal end-fire antenna with a high impedance ground surface structure and an array of radiating elements formed thereon. The ground surface structure includes an array of metal protrusions on a electrically conductive sheet, the metal protrusions arranged in a two-dimensional lattice. The ground surface structure acts as a magnetic surface at an RF frequency band of interest, functioning as an electrical short at DC, and as a mirror which reflects an RF field in the frequency band with virtually no phase reversal.
摘要:
A millimeter wave (MMW) antenna array includes a continuous transverse stub (CTS) radiating aperture comprising a set of spaced continuous transverse stubs, each having a longitudinal extent. A series feed system is coupled to an excitation source for exciting the stubs with MMW electromagnetic energy having a linear phase progression along the longitudinal extent of the stubs to produce an array beam which can be scanned over a beam scan range by changing the excitation frequency.
摘要:
A multilayer switching assembly for switching high frequency signals has MEMS structures on a ceramic substrate having a top surface, a bottom surface and a plurality of insulating layers. The insulating layers are separated by a first conductor and a second conductor. The first conductor is connected to a ground potential. The second conductor is separated from the first conductor by one of the insulating layers. The second conductor presents a specific impedance (50 ohms) with respect to the first conductor to high frequency signals traveling on the second conductor.64 MEMS structures are mounted on the top surface. Each MEMS has an input, an output, and a control. The input connected to the second conductor. The output is connected to a coplanar waveguide placed on the top surface. The control is connected to the bottom surface.The input to each MEMS is electrically shielded from the output and from the control by a third conductor connected to the first (grounded) conductor. The third conductor traverses one or more of the insulating layers thereby acting as a shield and precluding the high frequency signals presented to the input from propagating to the output and to the control. The 64 MEMS are arranged in a square 8 by 8 matrix, as well as their controls. High frequency inputs and outputs to be switched by the MEMS are placed on the periphery of the substrate to further enhance the separation of signals. Terminating resistors (50 ohms) are also placed near the periphery.
摘要:
A transmission line-to-waveguide transition that includes a microstrip impedance transformer for matching the impedance of an input transmission line to that of a flared slotline is disclosed. The slotline's width is sufficiently small such that when the transition is inserted into a waveguide the slotline is spaced inward from the waveguide's inner walls. A balun bi-directionally couples the unbalanced signal on the microstrip to a balanced signal on the slotline. The signal propagates along the slotline and is capacitively coupled to the waveguide. A trimmable tuning stub is used to adjust the resonant frequency of a parasitic cavity formed between the transition and the waveguide to increase the transition's effective bandwidth. A tapered dielectric insert is positioned inside the waveguide to decrease its size and to improve the coupling efficiency of the transition.
摘要:
A calibration and diagnostic system and method for evaluating the performance of a wide band array utilizing a true-time-delay beamforming network. A short pulse typically on the order of a 2 nanoseconds is synthesized by transmission of a large number of discrete, equally spaced frequencies over the bandwidth over a short period of time, during which the system response (amplitude and phase) is measured and stored in a computer. The collected data is then transformed into the time domain to demonstrate the range resolution of the system. By signal injection with a built-in calibration system, the setting of each programmable delay line of the array can be calibrated. A fiber-optic test set is used as a transponder in the far field to perform complete end-to-end tests of the array system.
摘要:
A dual-patch antenna includes a ground plane, a first patch plate parallel to and separated from the ground plane by a separation distance, and a second patch plate separated from the ground plane by the separation distance. The first and second patch plates are coplanar and separated by a radiating slot. An excitation probe isolatedly passes through the ground plane and connects to the first patch plate. A first wall connects an edge of the first patch plate to the ground plane. The first wall is located approximately ¼ wavelength of a mid-band operating frequency from the radiating slot. A second wall connects an edge of the second patch plate to the ground plane. The second wall is located approximately ¼ wavelength of the mid-band operating frequency from the radiating slot. The dual-patch antennas may be organized in an array.
摘要:
An electronically scanned antenna may include a plurality of space-fed, contiguous subarrays arranged in an annular region, each subarray including an inner set of radiating elements facing inwardly, an outer-facing set of radiating elements, and a feed system for illuminating the inner set of radiating elements. A plurality of RF amplifiers are coupled through a commutation switch matrix to selected ones of the subarray feed horn systems to illuminate a desired sector with RF energy.
摘要:
A space-fed conformal array for a high altitude airship includes a primary array lens assembly adapted for conformal mounting to a non-planar airship surface. The lens assembly includes a first set of radiator elements and a second set of radiator elements, the first set and the second set spaced apart by a spacing distance. The first set of radiators faces outwardly from the airship surface to provide a radiating aperture. The second set of radiators faces inwardly toward an inner space of the airship, for illumination by a feed array spaced from the second set of radiators.