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
System and method for evaluating equipment rack cooling performance
Method of fabricating semiconductor light emitting device
Sealed, waterproof digital electronic camera system and method of fabricating same
Method and system for cooling of integrated circuits
Authorization method for location based services
Systems and methods for authorizing, authenticating and accounting users having transparent computer access to a network using a gateway device
Single-wavelength correction method for luminescent homogeneous biological assay
  Randomly Featured Patents
Plural ferro-resonant power supplies for powering a magnetron where the aray lies in these power supplies being independent from each other and not utilizing any common components
Paper product
Environmentally benign anti-icing or deicing fluids employing triglyceride processing by-products
Method and device for evacuating gas tight envelope
Telescopic crane
Brush seal
Reprography process: color-copying with sublimable dyes
Bone milling template
Method and apparatus for channel prioritization
Automatic locking SCBA mounting bracket assembly