Phase-noise cancellation apparatus and method
AssigneeFuturewei Technologies, Inc.
InventorMarek Klemes
Life of this patent
Estimating the term…
Abstract
A noise cancellation method comprises receiving, by an adaptive phase-noise cancellation apparatus, an incoming symbol from a receiver, performing a hard decision process on the incoming symbol to generate a corresponding clean symbol of the incoming symbol, generating a conjugate instance of the corresponding clean symbol, multiplying the orthogonal instance of the incoming symbol by the conjugate instance of the corresponding clean symbol to generate an intermediate component and calculating a phase deviation of the incoming symbol based upon a real part of the intermediate component and an imaginary part of the intermediate component.
Claims23
A method comprising:
- receiving, by an adaptive phase-noise cancellation apparatus, an incoming symbol from a receiver;
- performing a hard decision process on the incoming symbol to generate a corresponding clean instance of the incoming symbol;
- generating a conjugate instance of the corresponding clean instance;
- generating an orthogonal instance of the incoming symbol;
- multiplying the orthogonal instance of the incoming symbol by the conjugate instance of the corresponding clean instance to generate an intermediate component;
- and
- calculating a phase deviation of the incoming symbol based upon a complex representation of the intermediate component.
An apparatus comprising:
- a first phase deviation estimate block configured to:
- receive a phase-noise corrupted symbol;
- generate a phase deviation of the phase-noise corrupted symbol at a first output of the first phase deviation estimate block;
- and
- generate a hard decision instance of the phase-noise corrupted symbol at a second output of the first phase deviation estimate block;
- a symbol matched noise reconstruction block having inputs coupled to the first phase deviation estimate block, wherein the symbol matched noise reconstruction block is configured to:
- generate an orthogonal instance of the hard decision instance of the phase-noise corrupted symbol;
- and
- generate a phase-noise component by multiplying the orthogonal instance of the hard decision instance of the phase-noise corrupted symbol by the phase deviation of the phase-noise corrupted symbol;
- and
- a symbol matched phase-noise cancellation block having a first input configured to receive the phase-noise corrupted symbol and a second input coupled to an output of the symbol matched noise reconstruction block, wherein the symbol matched noise cancellation block is configured to subtract the phase-noise component from the phase-noise corrupted symbol.
A method comprising:
- receiving, by an adaptive phase-noise cancellation apparatus, an inner symbol from a receiver, wherein the adaptive phase-noise cancellation apparatus is part of a quadrature amplitude modulation (QAM) demodulator of the receiver;
- generating an orthogonal instance {tilde over (x)}⊥(t) of the inner symbol;
- generating a conjugate instance x*(t) of a quantized inner symbol;
- and
- calculating a phase deviation of the inner symbol according to:
- δθ
- estimate
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- where δθestimate is the phase deviation, the inner symbol is selected according to a gating criterion GC, wherein the gating criterion is generated base upon a magnitude squared of the inner symbol.
Dependencies are inferred from the claim text.