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64-QAM DIGITALIZATION OF AN ANALOGUE MICROWAVE RADIO NETWORK
64-QAM DIGITALIZATION OF AN MICROWAVE A ANALOGUE RADIO NETWORK F. J. Witt, . W. T. Barnett, J. D. Hubbard " ABSTRACT With the emergence of new high capacity digital services, new modern digital networks are necessary to satisfy customer applications. However, the task is to provide digital connectivity that gives the best performance at the least cost. One way is accomplish this is to ret
MEDICAL IMAGING USING MICROWAVES AND ULTRASOUND
MEDICAL IMAGING USING MICROWAVES AND ULTRASOUND H. Ermert* ABSTRACT Based on analogies between microwaves and ultrasonic waves common proceduces for medical diagnostic imaging are summarized. Common problems as well as differences between microwaves and ultrasound are pointed out and resulting limitations with respect to this kind of application are discussed. Furthermore, activities in this
THE OPERATIONAL SOUNDING OF THE LOWER ATMOSPHERE FROM SATELLITES USING MILLIMETRE WAVES
THE OPERATIONAL SOUNDING MILLIMETRE WAVES OF THE LOWER ATMOSPHERE FROM SATELLITES USING D. R. PICK* ABSTRACT This paper discusses the increasing use of millimetre waves for passive sounding of the lowest 15 km of the atmosphere in support of the forecasting activities of the Meteorological Office. The paper starts with a brief discussion of the spectral features in the 23 to 200 GHz region
MILLIMETRE-WAVE ATMOSPHERIC PROPAGATION AND SYSTEM IMPLICATIONS
MILLIMETRE-WAVE ATMOSPHERIC PROPAGATION AND SYSTEM IMPLICATIONS A. Vander Vbrst * ABSTRACT The various factors involved in millimetre-wave atmospheric propagation are reviewed, with more emphasis on the frequency band 30-300 GHz. The following aspects are considered: moist air attenuation, profiling and altitude effects, hydrometeors, turbulence, atmospheric pollution, and system implicat
SUSPENDED SUBSTRATE FILTERS AND MULTIPLEXERS
SUSPENDED SUBSTRATE FILTERS AND MULTIPLEXERS J D RHODES* ABSTRACT The different configurations which may be used for broadband lowpass and highpass filters will be discussed for applications from 0.5 - 40 GHz. Diplexer design and their will be considered with application to broadband multiplexers examples of practical devices. Due to the limitations of loss, narrow band bandpass and ban
MICROWAVES AND FUTURE ESA PROGRAMMES
"MICRCOWAVES AND FUTURE ESA PROGRAMMES.. Giovanni Mica* ABSTRACT Based on the European Space Agency long term plans, the requirements systems, equipments and components are dicussed in the frame of the programmatic areas: the Earth Spacetelematics network. for microwave eight major
THE CHIRP UP-CONVERTER AND AMPLIFIER (CUCA) FOR THE ERS-1 RADAR ALTIMETER
THE CHIRP UP-CONVERTER AND AMPLIFIER (CUCA) FOR THE ERS-l RADAR ALTIMETER A. Battisti, W. Gardoni *, G.M. Paganuzzi *, D. Tresoldi * ABSTRACT The paper describes the microwave signal processor under development for the transmitting chain of the radar altimeter to be placed on board the ERS-l remote sensing satellite. The unit is fed by 450 MHz and 7.35 GHz signals coming from the radar chirp gene
A SURPRISING PHENOMENON: THE CHAOS
A very simple non linear circuit ( L,C, with negative conductance, fed by a sinusoIdal signal) described by a very simple mathematical model ( a piecewise linear characteristic analysis) can give very compliwhich are not a consequence of improper simcated results ( the CHAOS) plifications in calculus, but show surprising phenomenon.
DIRECT INTEGRATION METHODS OF NON-LINEAR MICROWAVE CIRCUITS
This paper reviews the problems encountered in analysing non-linear microwave networks. The solution of these networks involves solving a set of differential, difference and non-linear equations and it is important to choose a method for formulating these equations which results in efficient numerical solutions. The first part of the paper outlines the formulation of these equations and the seco
NON-LINEAR MICROWAVE CIRCUIT ANALYSIS USING HARMONIC BALANCE TECHNIQUES
The basic principles of harmonic balance methods for the periodic steady-state analysis of non-linear circuits are described. The problem of choosing suitable algorithms for the numerical solution is also discussed. The analysis of a class-C amplifier is given as an example of practical application. The advantages and limitations of harmonic balance techniques are considered.