Method and apparatus for defining and generating local oscillator signals for down converter

Patent 6442381 Issued on August 27, 2002. Estimated Expiration Date:

October 30, 2018. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

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Inventors

Application

No. 183588 filed on 10/30/1998

US Classes:

455/265, With local oscillator synchronization or locking455/318With specified local oscillator structure or coupling

Examiners

Primary: Urban, Edward F.
Assistant: Gesesse, Tilahun

Attorney, Agent or Firm

Blakely, Sokoloff, Taylor & Zafman LLP

Foreign Patent References

35 21 288 DE. 12/20/1886
0 019 412 EP. 05/20/1980
2 252 879 GB. 12/20/1988
WO 91/19360 WO. 12/20/1991

International Class

H04B 001/10

Abstract

A method and apparatus for defining and generating a digital waveform such as used for the local oscillator for a down converter in a receiver is disclosed. The method and apparatus is particularly useful where the digital waveform is not an integer submultiple of a reference signal. A plurality of different digital waveforms meeting the timing criteria but having different combinations of segments needed to meet the timing criteria are generated. Each of the digital waveforms so generated are tested in, for instance, a receiver to enable the selection of the best combination of segments.