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:
Aug. 11, 1998
Filed:
Mar. 19, 1996
Steven G Cairns, Louisburg, NC (US);
Ericsson Inc., Research Triangle Park, NC (US);
Abstract
In radio transmitting equipment that develops a carrier frequency using a mixer, techniques are used to 'shift' or 'hide' spurious mixer outputs so that they do not significantly degrade spectral purity of the transmitter output. These techniques generally involve establishing a predetermined frequency relationship between the two signals inputted to the transmitter mixer (TXIF (VCO) and TXLO) in addition to the relationship required to provide the desired difference frequency when the two signals are mixed in the mixer. By establishing a certain predetermined frequency relationship between these two signals it is possible to precisely locate the frequencies of the undesirable mixer output products so that they can be filtered out and/or fall onto the desired output frequency. While generally applicable, these techniques provide special advantages in equipment in which other considerations constrain the design of the transmitter circuitry and frequency inputs thereto.