We present the observation of a new intermediate redshift damped Lyα absorption system candidate, discovered in the course of a spectroscopic follow-up for identifying the sources detected in a 150Å-wide bandpass UV-imaging survey at 2000 Å. The system displays very strong Mg ii and Fe ii lines and a high Fe ii/Mg ii ratio, which, following photoionization models, indicates a very high neutral ...

A method for the ratiometric pH sensing using LysoSensor DND-192 is presented in this paper. It works in the physiological pH range. It is based on the use of two fluorophores which differ significantly in their lifetimes. As the discrimination of their emissions is performed through two different frequencies, this method can allow significant overlap of the emission spectra. A simple long-pass...

We propose a novel structure of complex-tap microwave photonic filter (MPF) employing an incoherent broadband optical source (BOS) and a programmable optical spectrum processor. By tailoring the optical spectral amplitude and phase, arbitrary complex continuous-time impulse responses of the MPF can be constructed. Frequency responses with a single flat-top, highly chirped, or arbitrary-shape pa...

We present the observation of a new intermediate redshift damped Lyα absorption system candidate, discovered in the course of a spectroscopic follow-up for identifying the sources detected in a 150Å-wide bandpass UV-imaging survey at 2000Å. The system displays very strong Mg ii and Fe ii lines and a high Fe ii/Mg ii ratio, which, following photoionization models, indicates a very high neutral h...

A novel compact microstrip dual-band bandpass filter(BPF) is developed with remarkably improved stopband characteristics. Two square open-loop resonators are embedded in a U-shaped resonator to achieve a significant size-reduction of the filter. Meanwhile, a cross-coupling between nonadjacent resonators is exploited to produce multiple transmission zeros in the stopbands of the filter. As a con...

Today’s direct-conversion SDR platforms are capable of tuning over extremely wide frequency ranges compared to traditional superheterodyne transceiver architectures. However, these radios can suffer from a number of problems due to a lack of front-end RF filtering, including poor dynamic range and desensitization. In this paper, we examine preliminary work on a tunable bandpass filter we are de...

This paper describes the design and implementation of a second-order switched-capacitor (SC) bandpass (BP) filter with very wide quality factor (Q) programmability range. The filter selectivity is digitally programmed by varying the effective sampling frequency of an SC branch, without modifying any capacitor value. The proposed approach allows a quasi-continuous Q-factor tunability avoiding, i...

This paper proposes asymmetrical step-impedance resonators bandpass filters (ASIRs) for suppressing a wide stopband, ensuing in size reduction and ease of fabrication. The filters have been designed at the operating frequency around 2.0 GHz using halfand quarter-wavelength asymmetrical step-impedance resonators. The concept of existent oddand even-mode characteristics is used to approve the pro...

In this paper a high performance Ultra Wide Band microstrip bandpass filter is presented. The filter is designed using λ/4 short circuited stubs to improve the performance of UWB. The designed filter is based on 5th order chebyshev low pass prototype with .1 dB passband ripples. The filter with total size of 45×11 mm operates within 3.1310.4 GHz, produces a fractional bandwidth of 106%. The fil...