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
Projection-type video-image display apparatus
Device for preparing a body fluid for a bacteriological analysis
Process for the preparation of morphinane analogues
System and method for testing an integrated circuit embedded in a system on a chip
Systems and methods for adaptive blind mode equalization
Antimony and germanium complexes useful for CVD/ALD of metal thin films
Additives for oil recovery from reservoirs
  Randomly Featured Patents
Lighting fixture
Output voltage regulation using rotor growth
Image search device and image search method
Packaging material and packages produced from the material for light-sensitive products
Method and apparatus for controlling read and write operations in a storage device
Clock
Variable composition switching device
Control signal generator
Cruise control device
Broadcasting system, broadcasting apparatus, broadcasting method and receiving apparatus