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:
Apr. 20, 2004
Filed:
Mar. 10, 2000
Barry R. Allen, Redondo Beach, CA (US);
Northrop Grumman Corporation, Redondo Beach, CA (US);
Abstract
An image reject sub-harmonic mixer that employs less components than known image reject mixers. The mixer includes a 90° RF coupler, two high pass filters, two anti-parallel diode pairs, two low pass filters and a 90° IF coupler. RF and LO signals are applied to isolated input ports of the 90° coupler. In-phase and quadrature-phase copies of the RF and LO signals are provided at output ports of the coupler. The diode pairs mix the RF and LO signals to generate first and second intermediate frequency signals that are separated in-phase. The high pass filters reject the IF signals to prevent IF power from coupling to the RF and LO ports of the coupler. The low pass filters pass the IF signal and reject the LO and RF signals. Image rejection is obtained by combining the IF outputs of the two diode pair in the 90° IF hybrid.