Title:
ZERO IF TRANSCEIVER
Document Type and Number:
WIPO Patent Application WO2002049224
Kind Code:
A3
Abstract:
A zero Intermediate Frequency (IF) transmitter and receiver are implemented within a transceiver to eliminate interference in the receive band. An output of a tunable high oscillator to generate a frequency source that is an integer multiple of the desired transmit LO frequency. The frequency source is coupled to an amplitude limiter and frequency divider. The output of the frequency divider is used as the transmit LO to directly upconvert baseband signals to the desired output frequency without the need for an IF stage. Direct upconversion of the baseband transmit signals without an IF stage eliminates spurious frequency products that are produced in the receive band.
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Inventors:
SEE PUAY HOE
PETERZELL PAUL E
WALKER BRETT C
PETERZELL PAUL E
WALKER BRETT C
Application Number:
PCT/US2001/050894
Publication Date:
March 13, 2003
Filing Date:
October 24, 2001
Export Citation:
Assignee:
QUALCOMM INC (US)
International Classes:
H04B1/30; H04B1/40; (IPC1-7): H04B1/30; H04B1/40
Foreign References:
| EP0798880A2 | 1997-10-01 | |||
| EP0865165A2 | 1998-09-16 |
Other References:
GOLDBERG L: "COMMUNICATIONS TECHNOLOGIES GOING TO SILICON AT ISSCC", ELECTRONIC DESIGN, PENTON PUBLISHING, CLEVELAND, OH, US, VOL. 43, NR. 4, PAGE(S) 95-96,100,102,, ISSN: 0013-4872, XP000501540
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