The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 22, 1993
Filed:
Apr. 30, 1992
J Bradford Cole, Chelmsford, MA (US);
Raytheon Company, Lexington, MA (US);
Abstract
A monopulse antenna system having a four quadrant array of antenna elements and a plurality of summing and differencing amplifiers coupled to the antenna elements for combining signals received by such antenna elements to provide such monopulse antenna with a sum antenna pattern, an azimuthal difference antenna pattern, and an elevation difference antenna pattern. The differencing amplifiers include a feedback network for increasing the common mode rejection ratio of the amplifier. The amplifiers includes a pair of transistors coupled to a voltage source through active loads and a common biasing network. The pair of transistors have electrodes connected to a common junction. A variable current source biasing network comprises a resistor voltage divider for producing an output voltage equal to a portion of a bias voltage produced at the common junction and a third transistor having a pair of electrodes coupled between the common junction and the voltage source. The output voltage produced by the voltage divider is fed to a control electrode of the third transistor to maintain the bias voltage at the common junction substantially constant with processing variations used to in the formation of the transistors.