The Cycle 5 design baseline for the Wide-Field Infrared Survey Telescope Astrophysics Focused Telescope Assets (WFIRST/AFTA) instrument includes a single wide-field channel (WFC) instrument for both imaging and slit-less spectroscopy. The only routinely moving part during scientific observations for this wide-field channel is the element wheel (EW) assembly. This filter-wheel assembly will have...

The design and experimental results of a 5-, 10and 23-pole lumped-element HTS bandpass filters for the applications in digital terrestrial television and other digital communication services is reported here. These filters are designed around 800 MHz centre frequency, 7.6 MHz bandwidth using end-coupled lumped element resonators on yttrium-barium-copper-oxide (YBCO) or thallium-barium-calcium-c...

The purpose of this study is to investigate the acoustic performance of mufflers. As a numerical scheme for analyzing an acoustic filter, the boundary element method is more suitable than are domain methods, such as the finite element method, which has to mesh the domain. However, the coefficient matrices established by the boundary element method are full and often non-symmetrical. In order to...

The WFPC2 Filter F160BW, also known as WOOD’s filter, was designed to transmit UV emission around 150nm and strongly block all other wavelengths. The filter has a unique construction where a thin film of sodium metal serves as the spectral element. However, sodium is a highly unstable and reactive metal, which makes the filter susceptible to changes over time. Herein we report a rapidly growing...

A simple design technique for a microwave lumped and transversal filter using constant-k filter sections is presented. The noise figure can be suppressed by source degeneration inductors, which are added to the transversal element. The filter elements are analytically derived based on the specification and the noise minimization. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 116...

Fabry-Perot Filters are major candidates for use as demultiplexers in wavelength division multiple access networks. In this paper we investigate the crosstalk limitations of such filters, compare their performances, and optimize the filter design to minimize the crosstalk degradation.

t is reported that millions of people are suffering from some kind of hearing impairment [1]. The number is climbing due to the increasing portion of elderly people in the world's population. While hearing loss is usually caused by permanent mechanical damage to the ear, there is no medicine to reverse it, and surgery offers little help. Thus, electronic hearing aids or pros-thetics are, so far...

A novel method is proposed to synthesize dual-band bandpass filters (BPFs) from a prototype lowpass filter. By implementing successive frequency transformations and circuit conversions, a new filter topology is obtained which consists of only admittance inverters and series or shunt resonators, and is thereby easy to be realized by using conventional distributed elements. A microstrip dual-band...