Transient simulation of narrowband bandpass filters used in microwave circuits is challenging because of matrix ill-conditioning. Here, such filters are modelled as the equivalent discrete-time form developed using a bilinear z-transform. The technique has been implemented in a general purpose transient circuit simulator and validated using a 1.7 GHz 5-section coaxial filter with a 0.9% bandwidth.

We describe a novel oscillator that converts continuous light energy into stable and spectrally pure microwave signals. This light-induced microwave oscillator (LIMO) consists of a pump laser and a feedback circuit, including an intensity modulator, an optical fiber delay line, a photodetector, an amplifier, and a filter. We develop a quasilinear theory and obtain expressions for the threshold ...

This paper presents a simple method for determining the dielectric constant of microwave PCB substrates. In the presented method, a bandpass microstrip filter on the PCB substrate with a user-predicted dielectric constant value is designed for a given center frequency, and it is implemented. The simulation results of the designed bandpass filter are obtained by the help of electromagnetic analy...

In this paper we present a fully tunable and reconfigurable single-laser multi-tap microwave photonic FIR filter that utilizes a special SM-to-MM combiner to sum the taps. The filter requires only a single laser source for all the taps and a passive component, a SM-to-MM combiner, for incoherent summing of signal. The SM-to-MM combiner does not produce optical interference during signal merging...

A time-domain technique is proposed for ultra-wideband (UWB) microstrip-filter design. The design technique uses the reflection coefficient (S11) specified in the frequency domain. When the frequency response of the UWB filter is given, the response will be approximated by a series of UWB pulses in the time domain. The UWB pulses are Gaussian pulses of the same bandwidth with different time del...

Nowadays, there is expanding interest in planar compact microstrip filters applied to microwave wireless system. The compact microstrip resonant cell (CMRC) and spiral compact microstrip resonant cell (SCMRC) are more and more popular in filter design due to their slow-wave and band-stop effects. In this paper, a novel double-folded SCMRC (DSCMRC) is proposed, analyzed and measured, which turns...

We propose and demonstrate, based on the concept of a microwave bandstop filter, two quantum wave bandstop filter structures. Both structures employ nanoscale gates in a heterojunction transistor to induce a quantum cavity connected by two one-dimensional wires. As the electron wavelength is changed by the gate voltage, we observed that, at certain gate voltages, the transmission of electron wa...

RF and microwave bandpass filters are key components for most of the recent communication systems. A conventional hairpin-line resonator size is normally very large. A Multi-folded hairpin line resonator filter helps to reduce the size, if the required selectivity characterstrics are not critical. This paper presents the design, simulation, optimization and test results of a new class of a 4-po...

In this paper a new approach to the synthesis of coupling matrices for microwave filters is presented. The new approach represents an advance on existing direct and optimization methods for coupling matrix synthesis in that it will exhaustively discover all possible coupling matrix solutions for a network if more than one exists. This enables a selection to be made of the set of coupling values...

This paper considers the detection of point sources in two-dimensional astronomical images. The detection scheme we propose is based on peak statistics. We discuss the example of the detection of far galaxies in cosmic microwave background experiments throughout the paper, although the method we present is totally general and can be used in many other fields of data analysis. We consider source...