Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
Quadrature modulation apparatus, method, program, and recording medium










Image Number 5 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
Image processing apparatus and image processing method
Transmission apparatus, receiving apparatus, method, and storage medium
Data recording apparatus with recording control based on defect block and control method thereof
Method of manufacturing semiconductor devices using ion implantation
Charge pump and method of biasing deep N-well in charge pump
Methods and apparatus for power amplifier calibration
String changing tool with a quick connector assembly and worm gear string cutter
  Randomly Featured Patents
Traveling wave tube phase correction loop
Method of making silicon carbide whisker sheet composites
Submerged self-stabilized cargo hose arm for a single point mooring system
Automatic circuit tester control system
Double patterning strategy for contact hole and trench in photolithography
Optical exposer
Method and apparatus for teaching musical instruments
Interactive toy sprinkler
Wireless shipboard data coupler
Method and apparatus for subsea flexible conduit installation