Quadrature modulator and calibration method

Details Quadrature modulator and calibration method Quadrature modulator and calibration method

2004-04-20

2009-06-16

Tran, Khai (Department: 2611)

Pulse or digital communications

Transmitters

Quadrature amplitude modulation

C455S126000

Reexamination Certificate

active

07548591

ABSTRACT:
A quadrature modulator and a method of calibrating same by applying a first test tone signal to an in-phase modulation branch input of the modulator and a ninety degree phase-shifted version of the first test tone signal to a quadrature modulation branch input of the modulator. The carrier leakage level in an output signal of the modulator is measured and in response base band dc offset voltages are adjusted to minimize the carrier leakage. A second test tone signal is applied to the in-phase modulation branch input and a ninety degree phase-shifted version of the second test tone signal to the quadrature modulation branch input. The level of an undesired upper sideband frequency component in the output signal is measured and in response base band gains the in-phase and quadrature modulation branches and a local oscillator phase error are adjusted to minimize the undesired sideband.

REFERENCES:
patent: 5396196 (1995-03-01), Blodgett
patent: 5881376 (1999-03-01), Lundberg et al.
patent: 6169463 (2001-01-01), Mohindra et al.
patent: 6185260 (2001-02-01), Ishii
patent: 6298096 (2001-10-01), Burgin
patent: 6421397 (2002-07-01), McVey
patent: 6771709 (2004-08-01), Huang et al.
patent: 2002/0137487 (2002-09-01), Yochem
patent: 0 598 585 (1994-05-01), None
patent: 2 213 006 (1989-08-01), None

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