Transfer Functions For The Reference Clock Jitter

Transfer functions for the reference clock jitter in a serial link such as the PCI Express 100 MHz reference clock are established for various clock and data recovery circuits (CDRCs). In addition, mathematical interrelationships between phase, period, and cycle-to-cycle jitter are established and phase jitter is used with the jitter transfer function. Numerical simulations are carried out for these transfer functions. Relevant eye-closure/total jitter at a certain bit error rate (BER) level for the receiver is estimated by applying these jitter transfer functions to the measured phase jitter of the reference clock over a range of transfer function parameters. Implications of this new development to serial link reference clock testing and specification formulation are discussed. 1

Decimative Multiplication of Entropy Arrays, with Application to Influenza

The use of the digital signal processing procedure of decimation is introduced as a tool to detect patterns of information entropy distribution and is applied to information entropy in influenza A segment 7. Decimation was able to reveal patterns of entropy accumulation in archival and emerging segment 7 sequences that were not apparent in the complete, undecimated data. The low entropy accumulation along the first 25% of segment 7, revealed by the three frames of decimation, may be a sign of regulation at both protein and RNA levels to conserve important viral functions. Low segment 7 entropy values from the 2009 H1N1 swine flu pandemic suggests either that: (1) the viruses causing the current outbreak have convergently evolved to their low entropy state or (2) more likely, not enough time has yet passed for the entropy to accumulate. Because of its dependence upon the periodicity of the codon, the decimative procedure should be generalizable to any biological system

Thompson, W.A. et al. Decimative Multiplication of Entropy Arrays, with Application to Influenza. Entropy, 2009, 11, 351-359

The sentence sixth line from the end of paragraph two on page 355, “The second synonymous mutation was another G=>A transition at position 600 that converted the CAG codon to CAA, without change of encoded amino acid.

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Decimative Multiplication of Entropy Arrays, with Application to Influenza

The use of the digital signal processing procedure of decimation is introduced as a tool to detect patterns of information entropy distribution and is applied to information entropy in influenza A segment 7. Decimation was able to reveal patterns of entropy accumulation in archival and emerging segment 7 sequences that were not apparent in the complete, undecimated data. The low entropy accumulation along the first 25% of segment 7, revealed by the three frames of decimation, may be a sign of regulation at both protein and RNA levels to conserve important viral functions. Low segment 7 entropy values from the 2009 H1N1 swine flu pandemic suggests either that: (1) the viruses causing the current outbreak have convergently evolved to their low entropy state or (2) more likely, not enough time has yet passed for the entropy to accumulate. Because of its dependence upon the periodicity of the codon, the decimative procedure should be generalizable to any biological system

A Novel Method for the Analysis of ESD Generators and Coupling using Frequency Domain

A concept for analyzing ESD generators and coupling to EUTs in the frequency domain is presented. Its novelty lies in not only taking the current shaping, but also the radiation effects of structural elements and electrical components located within the ESD generator into account, without discharging the ESD generator. This is achieved by using the frequency domain and substituting the electrical breakdown within the ESD generator (contact mode) for one port of a network analyzer. The network analyzer excites all the pulse forming and the radiating elements of the ESD generator as they would be excited during a discharge. This offers the advantage of an increased dynamic range of frequency domain techniques without having to simplify the complex radiation properties of real ESD simulators