Resources Contact Us Home
Quadrature signal conversion device

Image Number 4 for United States Patent #5764171.

A receiver including two sigma delta modulators used to convert a pair of analog quadrature signals into digital quadrature signals. In such sigma delta modulators the quantization noise is shifted into a frequency region in which no signal is present. A cross coupling between the filters is provided to improve the noise reduction without increasing the order of the filters. By providing the cross coupling, it is possible to obtain complex poles and zeros in the noise transfer function which do not have to appear in complex conjugate pairs which results in an increase of the noise suppression in a specified frequency range.

  Recently Added Patents
Magnetoresistive element and manufacturing method of the same
Group control method for machine type communication and mobile communication system using the method
Data processing system, data processing method, and image forming apparatus
Detection and use of low molecular-weight modulators of the cold-menthol receptor TRPM8
Radio frequency splitter
Transaction finance processing system and approach
  Randomly Featured Patents
Switching modulators and demodulators utilizing modified switching signal
Garment bag closure
Radiation detector element
Melamine molded foam, process for producing the same, and wiper
Method of and apparatus for sterile packaging using stacked packaging elements, especially plastic cups with varying wall thickness
Cyclone separator having a variable longitudinal profile
Multi-market optimized user interface assembly and a reprographic machine having same
Imaging lens for reading out image
Systems and methods for designing a high-precision narrowband digital filter for use in a communications system with high spectral efficiency
Collapsible box formed with bamboo strips