Efficient blind equalization for quadrature amplitude modulation
AssigneeMarvell International Ltd.
InventorKok-Wui Cheong
Life of this patent
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Abstract
Methods and apparatus are provided for receiving a signal transmitted with a quadrature amplitude modulation (QAM) constellation. In an embodiment of the invention, a blind equalization algorithm can be performed to equalize the signal, and a constellation recovery algorithm can be performed to identify a constellation index corresponding to the QAM constellation. The blind equalization algorithm can be altered based on the identified constellation index. The invention advantageously allows for relatively efficient and relatively reliable equalization of signals transmitted with an unknown QAM constellation.
Claims28
A method of receiving an input signal transmitted with one of a plurality of candidate quadrature amplitude modulation (QAM) constellations, said method comprising:
- performing, by blind equalization circuitry, a blind equalization algorithm on said input signal;
- performing, by constellation recovery circuitry, a constellation recovery algorithm on a signal responsive to said input signal to identify a constellation index corresponding to said one QAM constellation from a plurality of constellation indices corresponding to said plurality of candidate QAM constellations;
- and
- altering, by adaptation circuitry, said blind equalization algorithm based on said identified constellation index.
Circuitry for receiving an input signal transmitted with one of a plurality of candidate quadrature amplitude modulation (QAM) constellations, said circuitry comprising:
- blind equalization circuitry operable to receive said input signal, wherein said blind equalization circuitry comprises adaptation circuitry operable to alter operation of said blind equalization circuitry based on a constellation index corresponding to said one QAM constellation;
- and
- constellation recovery circuitry operable to receive a signal responsive to said input signal and to identify said constellation index from a plurality of constellation indices corresponding to said plurality of candidate QAM constellations.
Dependencies are inferred from the claim text.