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
Positive electrode active material for nonaqueous electrolyte secondary battery
Stool
Multilayer films having reduced curling
Secure soft SIM credential transfer
Liquid crystal display apparatus
Optoelectronic semiconductor chip comprising a reflective layer
Nuclear fuel assembly bottom nozzle
  Randomly Featured Patents
Scanner for scanning an object by means of ultrasonic radiation
Speech recognition apparatus and vehicle incorporating speech recognition apparatus
System and method for computing oral bone mineral density with a panoramic x-ray system
Vehicle locking system
Friction reducing lubricant for stent loading and stent delivery systems
Timing controller and display device including the same
Continuous method of manufacturing wire wound inductors and wire wound inductors thereby
Power tool
Gas discharge device
Shoe guard