摘要:
Two discrete transmit/receive (T/R) channels are implemented in a single common T/R module package having the capability of providing combined functions, control and power conditioning while utilizing a single multi-cavity, multi-layer substrate comprised of high or low temperature cofired ceramic layers. The ceramic layers have outer surfaces including respective metallization patterns of ground planes and stripline conductors as well as feedthroughs or vertical vias formed therein for providing three dimensional routing of both shielded RF and DC power and logic control signals so as to configure, among other things, a pair of RF manifold signal couplers which are embedded in the substrate and which transition to a multi-pin blind mate press-on RF connector assembly at the front end of the package. DC and logic input/output control signals are connected to a plurality of active circuit components including application specific integrated circuits (ASICs) and monolithic microwave integrated circuit chips (MMICs) via spring contact pads at the rear of the package. An RF connector assembly for coupling transmit and receive signals to and from the module is located at the front of the package. The RF transmit power amplifiers which generate most of the heat in the module package are located in a first pair of cavities formed in the substrate directly behind the RF connector assembly and are mounted directly on a pair of flat heat sink plates which are secured to the bottom of the substrate and acts as a thermal interface to an external heat exchanger such as a cold plate. A second pair of cavities in which are located the RF receive signal amplifiers and their respective receiver protector elements, is located beside the first pair of cavities directly behind the RF connector for reducing RF signal loss.
摘要:
Two discrete transmit/receive (T/R) channels are implemented in a single common T/R module package having the capability of providing combined functions, control and power conditioning while utilizing a single multi-cavity, multi-layer substrate comprised of high temperature cofired ceramic (HTCC) layers. The ceramic layers have outer surfaces including respective metallization patterns of ground planes and stripline conductors as well as feedthroughs or vertical vias formed therein for providing three dimensional routing of both shielded RF and DC power and logic control signals so as to configure, among other things, a pair of RF manifold signal couplers which are embedded in the substrate and which transition to a multi-pin blind mate press-on RF connector assembly at the front end of the package. DC and logic input/output control signals are connected to a plurality of active circuit components including application specific integrated circuits (ASICs) and monolithic microwave integrated circuit chips (MMICs) via spring contact pads at the rear of the package. The MMICs which generate substantially all of the heat are located in multi-level cavities formed in the substrate and are bonded directly to a generally flat a heat sink plate which is secured to the bottom of the substrate and acts as a thermal interface to an external heat exchanger such as a cold plate. DC power conditioning is also provided by a capacitive bank type of energy storage subassembly externally attached to the rear of the module package for supplying supplementary power to the module during peak power operation. The T/R module is one module of an array of like T/R modules coupled to an active aperture of a radar system.
摘要:
Two discrete transmit/receive (T/R) channels are implemented in a single common T/R module package having the capability of providing combined functions, control and power conditioning while utilizing a single multi-cavity, multi-layer substrate comprised of high temperature cofired ceramic (HTCC) layers. The ceramic layers have outer surfaces including respective metallization patterns of ground planes and stripline conductors as well as feedthroughs or vertical vias formed therein for providing three dimensional routing of both shielded RF and DC power and logic control signals so as to configure, among other things, a pair of RF manifold signal couplers which are embedded in the substrate and which transition to a multi-pin blind mate press-on RF connector assembly at the front end of the package. DC and logic input/output control signals are connected to a plurality of active circuit components including application specific integrated circuits (ASICs) and monolithic microwave integrated circuit chips (MMICs) via spring contact pads at the rear of the package. The T/R module is one module of an array of like T/R modules coupled to an active aperture of a radar system.
摘要:
A transmit/receive (T/R) module adapted for use in a radar system. The module has a unified structure including a layered substrate on and in which two T/R channel circuits are integrated. The channel circuits make use of power distribution, channel controller, and RF signal routing circuitry, partly on a channel shared basis. In the RF routing circuitry, respective coupler elements are employed to combine RF receive signals for output to an RF receive manifold and to split an RF transmit signal from a transmit manifold into separate RF transmit signals for input to the T/R channel circuits.
摘要:
A transmit/receive (T/R) module adapted for use in a radar system. The module has a unified structure including a layered substrate on and in which two T/R channel circuits are integrated. The channel circuits make use of power distribution, channel controller, and RF signal routing circuitry, partly on a channel shared basis. In the RF routing circuitry, respective coupler elements are employed to combine RF receive signals for output to an RF receive manifold and to split an RF transmit signal from a transmit manifold into separate RF transmit signals for input to the T/R channel circuits.
摘要:
An approach to rejecting input common-mode voltage variations in a sampler/converter that avoids the use of a differential amplifier in the signal path, and without introducing added distortion or noise. In one embodiment, the input common-mode variations are sensed on a pair of matched resistors that straddle the common mode analog inputs, on a node ‘Vcmi’. An alternative, switched-capacitor-based sensing scheme is also possible. Using this measured Vcmi, adjustments are then made to the rest of the sampler/converter to take out any variations observed at Vcmi.
摘要:
An approach to rejecting input common-mode voltage variations in a sampler/converter that avoids the use of a differential amplifier in the signal path, and without introducing added distortion or noise. In one embodiment, the input common-mode variations are sensed on a pair of matched resistors that straddle the common mode analog inputs, on a node ‘Vcmi’. An alternative, switched-capacitor-based sensing scheme is also possible. Using this measured Vcmi, adjustments are then made to the rest of the sampler/converter to take out any variations observed at Vcmi.
摘要:
A dual action biopsy needle scrapes tissue of cellular thickness from a lesion during forward and rearward reciprocations of the needle along its longitudinal axis of symmetry. A first sharp edge, formed by a beveled distal end of the needle, scrapes tissue during proximal-to-distal travel of the needle. A second sharp edge is provided by a transversely disposed slot formed in the needle near the first sharp edge. The second sharp edge scrapes tissue during distal-to-proximal travel of the needle. In a first embodiment, the second sharp edge is coincident with an exterior surface of the needle. In a second embodiment, the second sharp edge is elevated with respect to the exterior surface and in a third embodiment the second sharp edge is recessed. Additional embodiments include a second slot, a channel, and a hinge for enabling pivotal movement of the second and third sharp edges.
摘要:
A balloon angioplasty apparatus includes a guide wire, a balloon catheter, and a guide catheter. The balloon catheter has slots formed in it to define a plurality of elongate members between the slots. A joint is formed at the proximal, distal, and mid-point of each elongate member. Displacing the proximal and distal joints toward one another causes the respective middle joints to displace radially outwardly, and radial inward travel of the middle joints is caused by increasing the distance between the proximal and distal joints. A mesh that captures emboli overlies the jointed members and opens and closes with them. The guide catheter is used to close the joined members and the emboli-capturing mesh at the conclusion of the angioplasty procedure. In a second embodiment, the jointed members are formed in a delivery catheter. In a third embodiment, the jointed members are formed in a guide wire.
摘要:
A bioabsorbable marker is placed in soft tissue such as breast tissue near a lesion during a biopsy procedure. If tests prove the lesion to be malignant, the marker indicates the location of the lesion and the marker is removed surgically together with the lesion. If tests prove the lesion to be benign, there is no need to surgically remove the marker due to its bioabsorbability. One or more markers may be carried in an elongate, flexible marker carrier that is ensheathed within an elongate, flexible outer sheath. The flexible outer sheath is slidingly introduced into the proximal end of a biopsy needle until its distal free end protrudes from a port formed in the distal end of the biopsy needle. Retraction of the outer sheath relative to the marker carrier then exposes the marker carrier. The markers exit the marker carrier under their own inherent bias or an auxiliary bias is employed to eject them from the marker carrier. In a first embodiment, the bioabsorbable markers are hollow spheres made of polylactite acid. They are filled with iodine or other radiopaque material so that they are visible under X-rays and/or ultrasound. The radiopaque material is also bioabsorbable. In an additional embodiment, the hollow spheres are filled with an easily visible dye so that, when punctured, they provide a visible indication of a lesion's location. In another embodiment, they are filled with radioactive material and are inserted for therapeutic purposes in a lesion known to be malignant. Another embodiment provides solid markers, formed by pre-mixing together a radiopaque material and a bioabsorbable material. The solid markers may also include dyes and radioactive materials. In all embodiments, the markers may be spherical, cubical, pyramidal, pentagonal, or any other predetermined shape.