Direct Synthesis of Multiband Bandpass Filters With Generalized Frequency Transformation Methods

Synthesizing Microstrip Dual-Band Bandpass Filters Using Frequency Transformation and Circuit Conversion Technique

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...

UWB-Bandpass Filters with Improved Stopband Performance

Tunable Multiband Microwave Photonic Filters

The increasing demand for multifunctional devices, the use of cognitive wireless technology to solve the frequency resource shortage problem, as well as the capabilities and operational flexibility necessary to meet ever-changing environment result in an urgent need of multiband wireless communications. Spectral filter is an essential part of any communication systems, and in the case of multib...

Robust optimal granulometric bandpass filters

A granulometric bandpass "lter (GBF) passes certain size bands in a binary image. There exists an analytic formulation for the optimization of GBFs in terms of the granulometric size density of a random set. This size density plays the role of the power spectral density for optimization of linear "lters. An optimal "lter depends on the parameters governing the distribution of the random set. In...

Frequency-tunable Bandpass Filters with Constant Absolute Bandwidth and Improved Linearity

This paper presents a frequency-tunable bandpass filter with constant absolute bandwidth and improved linearity. The proposed resonator is composed of an open-ended transmission line with back-to-back varactor diodes loaded at one end. The back-to-back varactor diodes are used to enhance the linearity of the filter, which is better than that of the single varactor counterparts. A mixed electric...