Back to results
US 8,711,994 B2Granted
Methods for determining decoding order in a MIMO system with successive interference cancellation
AssigneeQUALCOMM Incorporated
InventorsGokhan Mergen, Subramanya P. Rao, Jonathan Sidi
Life of this patent
Estimating the term…
Abstract
Certain aspects provide a method for determining decoding order and reconstruction weights for decoded streams to be cancelled in a MIMO system with successive interference cancellation, based on estimates of the channel characteristics, the received composite signal and parameters of the system.
Claims19
An apparatus for wireless communications, comprising:
- a receiver configured to receive a composite wireless multiple input multiple output (MIMO) signal that comprises a plurality of separately encoded data streams;
- a processor configured to:
- select a decoding order for decoding the data streams using successive interference cancellation;
- decode a first stream of data based on the selected decoding order;
- generate a matrix, based on a channel estimate and a constant related to a traffic to pilot ratio;
- extract a column from the matrix to be a reconstruction weight vector of the decoded stream;
- cancel the interference of the decoded stream from the received signal before decoding remaining streams, based at least in part on the reconstruction weight vector;
- and
- update the decoding order of the remaining streams and continuing successive interference cancellation of the remaining streams.
6 more elements
An apparatus for wireless communications, comprising:
- a receiver configured to receive a composite wireless multiple input multiple output (MIMO) signal that comprises a plurality of separately encoded data streams;
- a processor configured to:
- select a decoding order for decoding the data streams using successive interference cancellation;
- decode a first stream of data based on the selected decoding order;
- cancel the interference of the decoded stream from the received signal before decoding remaining streams;
- update the decoding order of the remaining streams and continuing successive interference cancellation of the remaining streams;
- reconstruct the decoded stream by re-encoding and re-modulating the decoded stream to obtain a reconstructed stream;
- determine a reconstruction weight vector for the decoded stream;
- cancel the interference of the decoded stream on the received composite signal by scaling the reconstructed stream with the reconstruction weight vector and subtracting the result from the composite received signal;
- estimate the channel properties based on a received pilot signal;
- calculate a constant related to a traffic to pilot ratio, based on the characteristics of the stream;
- multiply the constant with the estimate of the channel from the pilot signal to generate a matrix;
- and
- extract one of the columns of the matrix to be the reconstruction weight vector of the decoded stream.
11 more elements
An apparatus for wireless communications, comprising:
- a receiver configured to receive a composite wireless multiple input multiple output (MIMO) signal that comprises a plurality of separately encoded data streams;
- decoding order selector configured to select a decoding order for decoding the data streams using successive interference cancellation;
- a decoder configured to decode a first stream of data based on the selected decoding order;
- a processor configured to generate a matrix based on a channel estimate and a constant related to a traffic to pilot ratio;
- and extract a column from the matrix to be a reconstruction weight vector of the decoded stream;
- a stream subtractor configured to cancel the interference of the decoded stream from the received signal before decoding remaining streams, based at least in part on the reconstruction weight vector;
- and
- wherein the decoding order selector is further configured to update the decoding order of the remaining streams and continuing successive interference cancellation of the remaining streams.
5 more elements
Dependencies are inferred from the claim text.