An integrated high-frequency narrow-band high-resolution synthesizer

An Integrated High-Frequency Narrow-Band High-Resolution Synthesizer

A frequency synthesizer employing a new digitalfrequency measurement method in a feedback loop is described. The synthesizer features high-frequency resolution and a high operating frequency. The mostly digital nature of the synthesizer and relaxed voltage-controlled oscillator requirements also make the synthesizer suitable for integration. Models for the synthesizer are developed and experime...

Narrow-band and wide-band high-speed recursive digital filters using single filter frequency masking techniques

In this paper the design of single filter frequency masking recursive filters is discussed. We briefly review the previously proposed lowpass narrow-band filters and propose a design method for highpass narrow-band filters. Wide-band filters are also discussed. The proposed approach uses several identical filters, except for periodicity, which are mapped to a single hardware structure using fol...

Integrated high-resolution tomography

A common problem in seismic tomography is the inadequate amount of data required for accurate traveltime inversion. The inherent nature in which data is acquired and the subsurface velocities of the survey area can result in a nonuniform distribution of raypaths. In such instances the statistical nature of tomographic inversion biases the solution to reflect the acquisition instead of the geolo...

A programmable digital frequency synthesizer for a high resolution nmr spectrometer

2014 A low-cost filterless multi-signal frequency and phase synthesizer based on digital techniques is described. Usual functions such as frequency, phase selection and modulation are direct TTL programmable. Although it is built primarily for NMR field stabilisation, homonuclear spin decoupling and resonance line observation purposes, other applications in the frequency phase domain can also b...

Microcarcinoid tumor diagnosed with high-resolution magnification endoscopy and narrow band imaging.