Codex Corporation

About: Codex Corporation is a based out in . It is known for research contribution in the topics: Signal & Network packet. The organization has 189 authors who have published 241 publications receiving 32205 citations.

Covariance and autocorrelation methods for vector linear prediction

Abstract: A novel least-squares formulation of the vector linear prediction (VLP) problem is presented. Based on this formulation, we develop two new design methods for obtaining the optimal vector predictor for frame-adaptive prediction: the covariance method and the autocorrelation method, which bear the names of the corresponding methods in scalar LPC analysis. Our formulation reveals several previously unrecognized properties of the resulting normal equation. Simulation results for VLP of speech waveforms confirm that the two proposed methods indeed give higher prediction gain than previously developed methods.

New forms of LS lattice algorithms and an analysis of their round-off error characteristics

Abstract: New formulas are presented for direct updating of the reflection coefficients in the a priori and a posteriori forms of the least squares (LS) lattice algorithms. An analysis of the numerical characteristics of the new LS lattice forms is given and a comparison is made with the numerical characteristics of the conventional LS lattice algorithms. Computer simulation results are provided on the numerical accuracy of conventional and new LS lattice algorithms for several values of finite word length.

Printed circuit board manufacturing method accommodates wave soldering and press fitting of components

Abstract: A first set of plated-through holes (12) in the printed circuit board (PCB) are covered by a protective solder mask (26) on the solder side of the PCB while a second set of plated-through holes (20) are exposed. Electrical components (22) are disposed on the component side with leads inserted in the second set of holes (20). Solder is prevented from flowing into the first set of holes (12) during wave soldering by the mask covering (26). Conductive pins (30) designed for press fitting into the first set of holes (12) are inserted therethrough to define connecting pins on each side of the PCB following wave soldering. This permits both a wave soldering and press fit operation to be accommodated.

Power on reset circuit having hysteresis inverters

Abstract: A power on reset circuit uses a first inverter with hysteresis operating in response to a first power supply potential to develop a first reset signal when the first power supply potential is greater than a first predetermined threshold. A second inverter with hysteresis also operates in response to the first power supply potential for developing a second reset signal when the first power supply potential is greater than a second predetermined threshold. The first reset signal disables the second inverter until the first power supply potential reaches the first predetermined threshold. A delay circuit delays the second reset signal to ensure the first power supply potential is fully operational before indicating a ready condition.

Backup power system

Abstract: Backup power is provided for primary power supplies that serve several loads by providing fewer backup power supplies than the number of primary power supplies, generating power fault information indicative of the failure status of the primary power supplies, and connecting the backup power supplies each in parallel to one of the failed primary power supplies in response to power fault signals.