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T.H. Pearce
ADC DYNAMIC RANGE IMPROVEMENT FOR WIDEBAND HF RECEIVERS

The development of 14 bit monolithic Analogue to Digital Converters (ADC’s) capable of sampling at 80 MHz has revived interest in digitising the entire 3-30 MHz High Frequency (HF) radio spectrum for use in wideband HF receivers. This enables the ADC to be placed close to the antenna so removing the need for analogue mixing as well as offering a multi-channel reception capability, using multiple digital synthesisers and direct conversion I, Q mixing to baseband ...

Vasili K. Semenov
SUPERCONDUCTOR ADCS BASED ON PROCESSING OF SINGLE FLUX QUANTA

Superconductor ADCs exist and their performance is quickly approaching to those of the best semiconductor counterparts. Deep cooling could complicate a broad spreading of the still exotic superconductor technology. However, the technology is highly attractive for invention or at least numerical simulations of novel conversion schemes.

J. Roztocil, D. Varga, M. Siroky
ASPECTS OF LOW DISTORTION SINE WAVE GENERATORS MEASUREMENT

This paper deals with testing of ultra-low distortion sine wave generators. Measurement of harmonic distortion based on lock-in amplifiers is described and practical results using fundamental-suppression method are presented.

Zygmunt Biernacki, Tadeusz Zloto, Marek Kurkowski, Pawel Ptak
ANALYSIS OF ACCURACY AND MEASUREMENTS OF FLOWING MEDIUM PARAMETERS BY MEANS OF A WAVE THERMOANEMOMETER SYSTEM

The paper analyses the measurement accuracy of selected parameters, such as flow velocity and temperature, of a flowing medium, by means of the thermoanemometric method. The core of the method relies on the Wave Thermoanemometer System constructed by one of the authors. The sources of boundary error components are analysed within the signal conversion channels of the WTS. Errors are examined by means of relevant mathematical expressions representing signal conversion both in the velocity measuring channel and in temperature measuring channel. The algorithms have been developed for perfect and for real conditions. The theoretical considerations have been verified by laboratory tests performed by computerized equipment.

A.A. Platonov, K. Jędrzejewski, J. Jasnos
MATHEMATICAL AND COMPUTER MODELS IN MULTI-PASS ADC DESIGN AND OPTIMISATION

The paper presents a mathematically grounded approach to the analysis and optimisation of multi-pass analogue-to-digital converters (MADCs) with the algorithmic forming the estimates of converted samples. The approach enables a comprehensive analysis of the converter work using a virtual model of MADC built on the basis of its mathematical model. This model is based on the extended optimal identification algorithms adapted to the particularities of A/D conversion. The obtained sub-optimal algorithms take into account all main parameters of the internal auxiliary ADC and other analogue elements of MADC. The results of advanced simulations confirm a full agreement of theoretical and experimental evaluations, as well as efficiency of the proposed approach as a tool for MADC design support.

Jan Fischer, Jan Vejdelek
REAL-TIME CORRECTION OF DC OFFSET OF LOW-COST AUDIO CODECS IN ACOUSTIC DIGITAL LOCK-IN AMPLIFIERS

In design of the DSP for acoustic applications it is appropriate to integrate a low-cost audio codec into their structure. Audio stereo codecs are able to achieve a high resolution of measurement on low frequencies of the input signal. But audio codecs are able to digitalize only signals of the acoustic origin, it means the signal without the DC part of frequency spectrum. In the majority of available DSP there are 2 independent AD converters and also 2 DA converters. But most of audio codecs create the DC offset during the conversion to the digital form, it means 0V voltage amplitude of input signal doesn’t correspond to 0HEX in hexadecimal form of output digital word. The solution how to achieve the required parameters with these low-cost audio codecs is founded in this project.

Matteo Parenti, Andrea Boni, Davide Vescovi
A 6-b 1Gsample/s SiGe BiCMOS A/D Converter

The paper describes the design of a 1GS/s 6-bit ADC in SiGe BiCMOS technology. Several techniques such as subranging, interpolation and averaging were implemented on the original flash architecture in order to achieve low power consumption without sacrificing linearity and dynamic performance.

U. Frühauf, E.-G. Kranz, H. Leuterer
DEMONSTRATOR FOR RESOLUTION INCREASE AND AUTO-CORRECTION IN EMBEDDED MEASUREMENT SYSTEMS

For investigation and training of students in the field of high resolution measurement technology was built an embedded measurement system with 16 bit resolution and additional modules for self-diagnostics and autocorrection, including a monitoring measurement system for evaluation.

Ján Šaliga, Szabolc Csernok
C-LANGUAGE FUNCTION CLASS FOR SIGNAL PROCESSING AT ADC TESTING

The paper presents some ideas and results from the attempt to create a comprehensive suite of data processing, C-language functions that enables simplifying the development of new, user oriented software for testing analog to digital converters according the IEEE standards 1057, 1241 and DYNAD. The developed function class covers both dynamic and histogram based test methods. Nowadays, it is prepared in the form of instrument driver - function panel (*.fp) for the software development package Lab Windows⁄CVI by National Instruments. All functions were developed, debugged and tested in this environment.
The paper also contains some results from comparing the new developed function class used in a developed examples of end-user applications with test data processing Matlab software by Kollar and Markus.

Stanislav Ďaďo, David Slepička
ADC TESTING BASED ON FREQUENCY ESTIMATION


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