NASA Scientific and Technical Aerospace Reports

with low precision components, and some mathematical properties of the modulation scheme. A CMOS chip has been
designed implementing the architecture.
Author
Very Large Scale Integration; Waveforms; Quadratures; Transmitters
20060002182 Sophia Univ., Tokyo, Japan
Relaxation-Based Algorithm by Variable Virtual Capacitors for Analysis of Large Stiff Nonlinear Networks
Tanaka, Mamoru; Asai, Mitsuo; 1987 IEEE International Symposium on Circuits and Systems, Volume 2; 1987, pp. 617-620;
In English; See also 20060002103; Copyright; Avail.: Other Sources
Stiff nonlinear state equations are converted to nonlinear nodal algebraic equations in each time step. In the new
algorithm, the nodal equations linearized by Newton Raphson (NR) method are converted to the linear virtual state equations
by inserting a virtual capacitor between each node and the reference node. And then, linear Gauss Seidel(GS) method is
applied to the linearized equations which are obtained in each time step h by applying Backward Euler (BE) method to the
state equations. The most important process is to change the values of the virtual capacitors in each step of the NR method
in order to converge solution and to speed up. Simulation results by Sophia Relaxation Program (SRP) are shown for DC
analysis of bipolar circuits and for transient analysis of SRAM MOS circuits.
Author
Algorithms; Nonlinear Equations; Equations of State; Capacitors; Waveforms; Relaxation Method (Mathematics)
20060002187 Syracuse Univ., NY, USA
Theoretical and Experimental Characterization of Multiconductor Transmission Lines
Sarkar, Tapan K.; Rahalarabi, Tawfik; Harrington, Roger F.; Djordjevic, Antonije R.; 1987 IEEE International Symposium on
Circuits and Systems, Volume 2; 1987, pp. 511-513; In English; See also 20060002103; Copyright; Avail.: Other Sources
The basic objective of this presentation is to outline a methodology for the analysis of multiconductor transmission lines
embedded in multiple lossy dielectric media. To check the accuracy of the theoretical analysis, we have compared the
theoretical results with experiment.
Author
Transmission Lines; Lossy Media; Embedding; Dielectrics
20060002189 Calgary Univ., Alberta, Canada
Design of Allpass Digital Ladder Networks Using Bilinear Transformation Integrators
Nowrouzian, B.; Turner, L. E.; Fong, R.; Lee, L. S.; 1987 IEEE International Symposium on Circuits and Systems, Volume
2; 1987, pp. 649-655; In English; See also 20060002103
Contract(s)/Grant(s): NSREC-A5715; Copyright; Avail.: Other Sources
A general procedure for designing two dimensional (2D) velocity filters based on array filters derived originally for
multichannel (multiple input single output) processing of the recordings of an array of sensors is presented. These filters can
be implemented in the frequency domain using the 2D Fast Fourier Transform. A specific case of velocity filters based on a
family of multichannel array filters obtained recently for attenuating a coherent interference in the array recordings is worked
out in detail.
Author
Integrators; Digital Filters; Multichannel Communication; Fourier Transformation
20060002190 Keio Univ., Japan
Period-doubling Bifurcation and Chaos in a Constrained Circuit
Inaba, Naohiko; Saito, Toshimichi; Mori, Shinsaku; 1987 IEEE International Symposium on Circuits and Systems, Volume
2; 1987, pp. 668-671; In English; See also 20060002103; Copyright; Avail.: Other Sources
It is shown that the phenomena such as a period-doubling bifurcation and chaos generated in the Shinrikis’ circuit could
be well explained by a simplified model which we here after call as the Ideal Model. Here the idealization means that the
diodes in the circuit operate as an ideal switch. It is considered that the Ideal Model is the simplest chaos generating circuit
because it is constructed from 3 reactance elements, one negative resistance and only one nonlinear element constructed from
diodes where the operation of such nonlinear element is extremely simple. From this model, Poincar_ map could be derived
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