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:
May. 01, 2001
Filed:
Sep. 15, 1998
Nortel Networks Limited, Montreal, CA;
Abstract
To reduce the impact of image frequencies generated by mixing an incident carrier signal down to a relatively low intermediate frequency signal used in subsequent signal processing, a mixing frequency is selected such that the generated intermediate frequency signal has a frequency offset relative to DC that is substantially that of a single channel spacing between frequency adjacent incident carrier signals, as shown in FIG.,Image rejection is further improved through the integration of a current-driven polyphase filter (,) directly between an input stage (Q,to Q,) and a mixer stage (Q,to Q,) of an image reject mixer (FIG.,) such as to mitigate quadrature divergence between separate in-phase and quadrature paths within the image reject mixer.