Resources Contact Us Home
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
System and method for reliable packet data transport in a computer network
LO generation with deskewed input oscillator signal
Position-measuring device
Integrated circuits with magnetic core inductors and methods of fabrications thereof
Apparatus, electronic component and method for generating reference voltage
Modified binding proteins inhibiting the VEGF-A receptor interaction
  Randomly Featured Patents
Ink jet recording head and method manufacturing thereof
Polyamide supported metallocene catalysts
System and method for sharing SATA drives in active-active RAID controller system
Thermoplastic linoleum
Smoke opacity detector
Air circulation system
Catalytic dewaxing process
Method to reduce stool odor of companion animals
Pressure oil energy recover/regenation apparatus
Methods and apparatus for optical network management using pilot tones