Hewlett-packard Company

Bich N Nguyen

John F Schipper

Stuart L Carp

Abdul Wahid Khan

Howard L Swain

String light storage container

Method and apparatus for calibration of sensors and transducers that (a) takes account of the fact that the output variable value may behave differently as a function of the input variable value in different regions of the input variable value and (b) takes account of variation of the output variable value with changes in a plurality of supplemental variables, for a fixed value of the input variable. A discrete set of reference values of each supplemental variable is chosen, and the representation of output variable value as a function of input variable value is determined for each of the set of reference values of the supplemental variables. The representation is then extended to arbitrary values of the supplemental variables by linear or quadratic interpolation.

Multiple variable compensation for transducers

A fast switching broadband signal synthesizer method and structure are provided which not only has the ability to change frequency and amplitude quickly, but with a minimal dwell time required before switching can again take place. A signal translator can also be constructed in accordance with this invention in order to convert the output frequency of a companion signal source to any desired frequency while retaining the fast switching speed and switching rate of the signal synthesizer. Amplitude, phase, and frequency modulation of the companion signal are preserved during the translation process. A direct frequency synthesizer is provided wherein internal signals which are combined to generate any output frequency are derived from a single fixed frequency oscillator. By utilizing a single reference frequency oscillator in accordance with this invention, the amount of circuitry required to construct a direct frequency synthesizer is greatly reduced. Because all internal signals are derived from one reference frequency oscillator, the close-in-phase noise of the internal signals are correlated, thus providing an output signal having low phase noise. All internal frequency increments and number of frequency selector switch positions have numerical values that are an exact-power-of-two.

Growing community of inventors

San Jose, CA, United States of America

Bich N Nguyen