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. 11, 2002
Filed:
Oct. 29, 1998
Edmund Goetz, Dachau, DE;
Shen Feng, München, DE;
Markus Scholz, München, DE;
Georg Lipperer, München, DE;
Stefan Beyer, Mering, DE;
Siemens Aktiengesellschaft, Munich, DE;
Abstract
A frequency synthesizer for a radio terminal with which a dual-band and/or dual-mode switchover is possible in a simple manner. The frequency synthesizer has a double phase-locked loop with a high-frequency portion and an intermediate-frequency portion, each with one divider and one counter in a feedback branch. There is at least one memory for holding a plurality of divider values for the counter in the intermediate-frequency portion. The counter in the high-frequency portion is coupled to the memory in such a way that when a new divider value is written into the counter of the high-frequency portion, an associated divider value from the memory is written into the counter of the intermediate-frequency portion. In this way, the frequency generated by the intermediate-frequency divider is adapted to the frequency generated in the high-frequency portion in such a way that the requisite operating frequencies of each active mobile radio system are set automatically. In the same way, the dual-mode switchover can be carried out by coupling a further memory with further divider values for the counter of the high-frequency portion.