Component design, development, and testing of an inductive voltage adder (IVA) system for Jupiter
Jupiter is a proposed 15-20 MJ laboratory X-ray source. It would store /spl sim/100 MJ in the Marx generators and deliver /spl sim/500 TW to drive high power z-pinch implosions. The pulsed power requirements for Jupiter were evaluated by a national review panel which concluded that the modular IVA technology as used in HERMES III is capable of meeting these requirements. Modularity of construction permits design verification with less than a full size system and offers the flexibility to meet changing requirements. A program to validate this approach at the required power levels has begun with the construction and testing of components that will comprise a full scale IVA generator module. The IVA module will provide a nominal 10 MV, 1.8 MA, 100 ns FWHM output pulse and will consist of four submodules. Each submodule is composed of a Marx generator, two intermediate energy storage capacitors (ISCs) four pulse forming lines (PFLs), one voltage adder cavity (VAC), plus other associated switches and hardware. A conceptual design for this IVA module has been completed. Initial designs for the ISC, PFL, and their gas switches are also complete and hardware has been procured. Testing of these components is underway at Sandia National Laboratories. Discussions of these designs and results of tests are presented in this paper.
Double-Bounce Switching
Abstract : Double-bounce switching is a technique for exploiting traveling waves in a transmission-line-type pulse forming system to reduce voltage requirements on pulse forming line (PFL) output switches. If a simple PFL (a de charged ideal transmission line with characteristic impedance Z) is switched into a matched load, then peak output power is v2/4Z, where V is output switch voltage. If the PFL is pulse-charged by another transmission line, and if geometries, circuit parameters, and switch points are chosen properly, then the PFL can inject a power much larger than v2/4Z into a matched load. This is the principle of double-bounce switching (so called because it exploits a doubly reflected charging wave in the PFL). Data from EAGLE experiments are presented which demonstrate that the technique works in a real geometry.
Third order nonlinear distortion of SAW duplexers in UMTS system
Nonlinearity distortion characterization and accurate modeling techniques for leaky surface acoustic wave (LSAW) devices have been desired in the recently years due to the applications of the Radio Frequency (RF) SAW duplexers in the third-generation (3G) telecommunication system, such as Universal Mobile Telecommunications System (UMTS). In the work, we first discuss the approaches to measure and characterize the 3rd order harmonic generation of the resonators on lithium tantalate YXl42° wafer and YXl48° wafer, with resonance frequency of 800MHz to 900 MHz; Second, we present an effective nonlinear Butterworth-van-Dyke (BVD) model to simulate the multi-tone 3rd order intermodulation effects of a band 5 duplexer; simulation result vs. measurement of 3rd order harmonic generation, 3rd order intermodulation (IMD3) and triple beat are presented.