The Experts below are selected from a list of 29151 Experts worldwide ranked by ideXlab platform
I Smith - One of the best experts on this subject based on the ideXlab platform.
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high power short Pulse Generators based on induction voltage adders
Proceedings of the IEEE, 1992Co-Authors: J J Ramirez, K R Prestwich, I SmithAbstract:High-power, short-Pulse Generators based on induction voltage adders were identified by the Pulsed power community as the most important recent advance in this field. These systems use linear induction accelerator modules and self-magnetically insulated vacuum transmission lines to generate high-voltage (tens of megavolts), moderate-impedance ( >
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high power short Pulse Generators based on induction voltage adders Pulsed power technology
Proceedings of the IEEE, 1992Co-Authors: J J Ramirez, K R Prestwich, I SmithAbstract:High-power, short-Pulse Generators based on induction voltage adders were identified by the Pulsed power community as the most important recent advance in this field. These systems use linear induction accelerator modules and self-magnetically insulated vacuum transmission lines to generate high-voltage (tens of megavolts), moderate-impedance (≤200 Ω), short-duration (tens of nanoseconds) output Pulses. Hermes III is a 20-MV, 16-TW electron beam accelerator and represents the most powerful implementation to date of the induction voltage adder technology
J J Ramirez - One of the best experts on this subject based on the ideXlab platform.
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high power short Pulse Generators based on induction voltage adders
Proceedings of the IEEE, 1992Co-Authors: J J Ramirez, K R Prestwich, I SmithAbstract:High-power, short-Pulse Generators based on induction voltage adders were identified by the Pulsed power community as the most important recent advance in this field. These systems use linear induction accelerator modules and self-magnetically insulated vacuum transmission lines to generate high-voltage (tens of megavolts), moderate-impedance ( >
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high power short Pulse Generators based on induction voltage adders Pulsed power technology
Proceedings of the IEEE, 1992Co-Authors: J J Ramirez, K R Prestwich, I SmithAbstract:High-power, short-Pulse Generators based on induction voltage adders were identified by the Pulsed power community as the most important recent advance in this field. These systems use linear induction accelerator modules and self-magnetically insulated vacuum transmission lines to generate high-voltage (tens of megavolts), moderate-impedance (≤200 Ω), short-duration (tens of nanoseconds) output Pulses. Hermes III is a 20-MV, 16-TW electron beam accelerator and represents the most powerful implementation to date of the induction voltage adder technology
Anantha P Chandrakasan - One of the best experts on this subject based on the ideXlab platform.
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gaussian Pulse Generators for subbanded ultra wideband transmitters
IEEE Transactions on Microwave Theory and Techniques, 2006Co-Authors: David D Wentzloff, Anantha P ChandrakasanAbstract:This paper presents calculations for approximating the measured spectrum of Pulsed signals in the high and low Pulse-repetition-frequency (PRF) region. Experimentally verified peak and average power calculations are presented for Pulse trains with no modulation and when modulated by random data using binary phase-shift keying (BPSK). A Pulse generator is presented that is built using commercially available discrete components. BPSK Pulses are generated at a PRF of 50 MHz. The output spectrum has a center frequency of 5.355 GHz and a -10-dB bandwidth of 550 MHz. A technique for Pulse shaping is presented that approximates a Gaussian Pulse by exploiting the exponential behavior of a bipolar junction transistor. This technique is demonstrated by a Pulse generator fabricated in a 0.18-/spl mu/m SiGe BiCMOS process. BPSK Pulses are generated by inverting a local oscillator signal as opposed to the reference Pulse, improving matching. Pulses are transmitted at a PRF of 100 MHz and centered in 528-MHz-wide channels equally spaced within the 3.1-10.6-GHz ultra-wideband band. Measurement results for both transmitters match well with calculated values.
F. Alesch - One of the best experts on this subject based on the ideXlab platform.
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Technical analysis of dual channel Pulse Generators used in deep brain stimulation; a safety evaluation.
Acta Neurochirurgica, 2008Co-Authors: Hermann Lanmüller, Johann Wernisch, F. AleschAbstract:Background A sudden failure of implantable Pulse Generators (IPG) occurred in 15 out of 143 units during the last 4 years in our patients. This corresponds to a failure rate of 10.5%. In all cases, the connection between the causes of battery and electronic circuit was found defective in the destructive analysis. In order to better understand the failure causes we proceeded to an analysis of explanted IPGs which had reached their normal life span due to depletion of the battery.
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Sudden failure of implantable Pulse Generators: cause of failure and examination.
Biomedizinische Technik, 2007Co-Authors: Hermann Lanmüller, Johanna Buchroithner, Johann Wernisch, F. AleschAbstract:A sudden failure of implantable Pulse Generators used for spinal cord stimulation occurred in two patients. To identify the cause of this failure, an intensive destructive analysis of the explanted devices was carried out. A functional diagnosis was carried out by inspecting amplitude, Pulse width and frequency on each output channel of the implantable Pulse Generators. Later, the titanium case of the Pulse Generators was opened by laser cutting to minimise any additional mechanical stress during the opening procedure. The functional test for both Pulse Generators showed faultless behaviour. Using light and electron microscopy, hairline cracks could be identified in the electrical connection between battery and electronic circuit. In both devices, the cracks spread through the whole bond wire in the connection to the plus pole of the battery and partially also to the minus pole. The analysis showed that both devices failed by broken bond wires. The electrical connection to the battery exists just by the spring characteristic of the wires. A push to the implant causes a short-term disconnection, resulting in a power on reset of the device. Manufacturing or design issues, allowing micromotion between battery and the hybrid part, may be the reason for this problem.
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sudden failure of dual channel Pulse Generators
Movement Disorders, 2005Co-Authors: F. AleschAbstract:We report a series of four sudden hardware failures in dual channel Pulse Generators implanted for chronic stimulation of the subthalamic nucleus in the treatment of Parkinson's disease. In all cases, a sudden and severe deterioration of the patient's neurological condition occurred with symptoms similar to those present before surgery. In all cases, destructive analysis of the generator revealed a fracture of the wire bonds connecting the battery to the hybrid (electronic) part of the Pulse generator. This fracture led to repeated Power On Resets, bringing the parameter settings back to default (factory settings). As a cause, we propose that relative movements between the hybrid and the battery led to low cycle fatigue fractures due to insufficient stiffness of the device. That three of four failures occurred when the implant was in the infracostal region makes it likely that the fractures depend on the mechanical stress applied to the device. The efficacy of the therapy resumed immediately after device replacement. As a corrective measure, the manufacturer has added epoxy between both components, increasing significantly the stiffness of the device.
K R Prestwich - One of the best experts on this subject based on the ideXlab platform.
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high power short Pulse Generators based on induction voltage adders
Proceedings of the IEEE, 1992Co-Authors: J J Ramirez, K R Prestwich, I SmithAbstract:High-power, short-Pulse Generators based on induction voltage adders were identified by the Pulsed power community as the most important recent advance in this field. These systems use linear induction accelerator modules and self-magnetically insulated vacuum transmission lines to generate high-voltage (tens of megavolts), moderate-impedance ( >
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high power short Pulse Generators based on induction voltage adders Pulsed power technology
Proceedings of the IEEE, 1992Co-Authors: J J Ramirez, K R Prestwich, I SmithAbstract:High-power, short-Pulse Generators based on induction voltage adders were identified by the Pulsed power community as the most important recent advance in this field. These systems use linear induction accelerator modules and self-magnetically insulated vacuum transmission lines to generate high-voltage (tens of megavolts), moderate-impedance (≤200 Ω), short-duration (tens of nanoseconds) output Pulses. Hermes III is a 20-MV, 16-TW electron beam accelerator and represents the most powerful implementation to date of the induction voltage adder technology
