Resources Contact Us Home
Low noise active mixer

Image Number 2 for United States Patent #5379457.

In a conventional Gilbert-cell active mixer, two local oscillator matched pairs of transistors receive a local oscillator input signal and are coupled to a radio frequency matched pair of transistors which receive a radio frequency input signal. The circuit generates an intermodulated output signal at the collectors of the local oscillator matched pairs. Noise degradation is reduced over the conventional mixer by replacing the standard radio frequency emitter degeneration resistor with a reactive element, thereby reducing thermal noise. Narrow-band input matching is achieved by insertion of a series inductive element and optional parallel capacitive element in line with the radio frequency input. Thermal noise contributed to the circuit is thereby minimized while circuit linearity is preserved in the narrow frequency band of interest.

  Recently Added Patents
Wake-up radio system
Wireless monitoring in process applications
Accelerator for a read-channel design and simulation tool
Mechanism for visible users and groups
Computer device with digitizer calibration system and method
System and method for configuring a direct lift control system of a vehicle
  Randomly Featured Patents
Road roller vehicle with water applicator
High voltage relay
System for lifting and lowering a sailboat mast
Configurable computer enclosure
Surface enhanced raman detection on metalized nanostructured polymer films
Silicon steel and processing therefore
Mobile communication system
Method and apparatus for providing optical network interface using optical memory storage
Tampon for feminine hygiene or medical purposes, and process for producing the same
Region-based information compaction as for digital images