A TUNEABLE CIRCUIT FOR CANCELING THIRD ORDER MODULATION

Title:

A TUNEABLE CIRCUIT FOR CANCELING THIRD ORDER MODULATION

Document Type and Number:

WIPO Patent Application WO/2005/109628

Kind Code:

A1

Abstract:

A CMOS transconductor for cancelling third-order intermodulation is provided. The transconductor includes a transconductance circuit and a tuneable distortion circuit. The transconductance circuit takes an input voltage and generates an output current having a transconductance element and an IM3 element. The distortion circuit takes the same input voltage and generates a current having an IM3 element of equal amplitude and opposite phase to the IM3 element of the transconductance circuit. A controller circuit tunes the distortion circuit to adjust its IM3 element to substantially equal the amplitude of the IM3 of the transconductance circuit. The distortion and transconductance circuits are arranged to sum their output currents thereby effectively cancelling the IM3 elements, leaving the transconductance relatively unmodified.

Inventors:

MANKU TAJINDER (CA)

Application Number:

PCT/CA2005/000798

Publication Date:

November 17, 2005

Filing Date:

May 12, 2005

Export Citation:

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Assignee:

SIRIFIC WIRELESS CORP (CA)
MANKU TAJINDER (CA)

International Classes:

H03B1/04; H03C1/06; H03D1/02; H03D7/14; H03F1/32; H03F3/18; H03F3/45; H03K5/01; H03K5/02; H03K5/1252; H04B1/04; H04B1/12; H04B15/06; H04B1/40; (IPC1-7): H03F1/32; H03K5/01; H04B1/38; H04B15/06; H04B1/12; H03F3/18; H03D1/02; H03C1/06

Foreign References:

EP1345320A2	2003-09-17
GB2223902A	1990-04-18
US4422051A	1983-12-20
US6515542B1	2003-02-04
US5497123A	1996-03-05
US4720685A	1988-01-19

Other References: