Resources Contact Us Home
Quadrature modulation apparatus, method, program, and recording medium

Image Number 8 for United States Patent #7944989.

An RF signal, which has been obtained by a quadrature modulation, is corrected without performing quadrature demodulation. There are included an in-phase multiplier, a quadrature multiplier, an adder, a power detector, and an error determining part. The in-phase multiplier outputs an in-phase conversion signal by mixing an in-phase local signal of a predetermined local frequency with an in-phase correction user signal obtained by adding an in-phase user signal to an in-phase correction signal of a sinusoidal voltage outputted from an in-phase correction signal output unit. The quadrature multiplier outputs a quadrature conversion signal by mixing a quadrature local signal, which is different in phase by 90 degrees from the in-phase local signal, with a quadrature correction user signal obtained by adding a quadrature user signal to a quadrature correction signal, which is different in phase by 90 degrees from the in-phase correction signal, from a quadrature correction signal output unit. The adder adds the in-phase conversion signal to the quadrature conversion signal. The power detector measures an output voltage of the adder. The error determining part determines, based on the measurement result of the power detector, the error of the quadrature modulation.

  Recently Added Patents
Pattern forming method using developer containing organic solvent and rinsing solution for use in the pattern forming method
Regenerative braking control to mitigate powertrain oscillation
Electric washing machine
Thermoforming sheet loading apparatus and method
Haloalky -substituted amides as insecticides and acaricides
Circuit arrangement for a piezo transformer, and method therefor
Methods and apparatus for performing multiple photoresist layer development and etching processes
  Randomly Featured Patents
Sanitary faucet
Electron emission device with black layer and method of preparing the same
Cloth detection system for an automatic washer
Lens unit and compact image pickup module
Fast tracking of PN synchronization in a direct-sequence spread-spectrum digital communications system
Watch bezel/lens/rocker switch assembly
Testis-specific insulin homolog polypeptides
Self-adjusting motor mount for drive motors of a pen plotter
Polyphenylene ether capped with salicylic acid ester
Highly elongated single component, non-corrosive RTV silicone compositions