Automatic Tuning for Linearly Tunable Filters. (May 2004) Sung-Ling Huang, B.S., Tatung Institute of Technology, Taiwan; M.S., Tatung Institute of Technology, Taiwan Chair of Advisory Committee: Dr. Aydin I. Karsilayan A new tuning scheme for linearly tunable high-Q filters is proposed. The tuning method is based on using the phase information for both frequency and Q factor tuning. There is no...

It is very effective way to utilize a very wide tunable filter in co-existing multi-standards wireless communications environment. Especially, as the long term evolution (LTE) communication era has come, the multi-band coverage is one of the important features required for the RF components. In this paper, we present the frequency conversion technique, and so generate two types of RF filters wh...

Two-dimensional temperature measurements using filtered Rayleigh scattering (FRS) have been demonstrated. A tunable single-longitudinal-mode alexandrite laser was employed to provide the tunable narrow-line-width ultraviolet laser beam at 254 nm. Isotopic-enhanced mercury was utilized as an ultraviolet atomic filter. The strong absorption of the filter enabled effective suppression of elastic b...

A tunable photonic microwave bandpass filter with negative coefficient based on an electro-optic phase modulator (EOPM) and a variable polarization beamsplitter (VPBS) is demonstrated. A two-tap microwave bandpass filter with one negative coefficient is presented. The chromatic dispersion and optical coherence are not affected on this filter. Keywords—Bandpass filter, EOPM, photonic microwave f...

We propose and experimentally demonstrate a wavelength and bandwidth-tunable comb filter based on silicon Sagnac loop mirrors (SLMs) with Mach-Zehnder interferometer (MZI) couplers. By thermally tuning the MZI couplers in common and differential modes, the phase shift and reflectivity of the SLMs can be changed, respectively, leading to tunable wavelength and bandwidth of the comb filter. The f...

In software radio systems, a digital IIR filter offers good roll-off and transition bandwidth characteristics using a low amount of arithmetic components, thus simplifying hardware implementation. However, IIR filter structures are very sensitive to finite precision compared to FIR filter structures. In order to design a high quality, low component count, digital narrowband bandpass filter onto...

A scheme for photonic generation of pulsed microwave signals with tunable frequency and phase based on optical spectral-shaping and frequency-to-time mapping is proposed and experimentally demonstrated. The spectral shaping is realized by a tunable optical comb filter consisting of a differential group delay (DGD) element, a polarization modulator (PolM), and a polarizer. By passing a short opt...