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US 2006/0141933 A1Published application
Channel estimation for interference cancellation
AssigneeQUALCOMM Incorporated
InventorsJohn Smee, Henry Pfister, Jilei Hou, Stefano Tomasin
Life of this patent
Estimating the term…
Abstract
A method and system for interference cancellation (IC). One aspect relates to traffic interference cancellation. Another aspect relates to joint IC for pilot, overhead and data. Another aspect relates to improved channel estimation. Another aspect relates to adaptation of transmit subchannel gains.
Claims17
A method comprising:
- receiving data samples of signals transmitted from a plurality of access terminals;
- despreading the received data samples with pilot chips associated with a first access terminal;
- demodulating the despread data samples into data symbols;
- decoding the demodulated data symbols;
- determining whether the demodulated data symbols were correctly decoded;
- if the demodulated data symbols were correctly decoded, using the decoded, demodulated data symbols to regenerate data chips transmitted by the first access terminal;
- despreading the received data samples with the regenerated, transmitted data chips to determine a channel estimate;
- storing the data samples received from the plurality of access terminals in a buffer;
- using the determined channel estimate to reconstruct data samples transmitted from the first access terminal;
- and
- subtracting the reconstructed data samples sent from the first access terminal from the stored data samples in the buffer.
8 more elements
A base station comprising:
- a memory configured to store data samples of signals received from a plurality of access terminals;
- a demodulator configured to despread and demodulate the stored data samples using a first code sequence corresponding to a first access terminal;
- a decoder configured to decode data from the demodulated data;
- a regeneration unit configured to use correctly decoded data to regenerate data chips transmitted by the first access terminal;
- a channel estimator configured to despread the stored data samples with the regenerated data chips to determine a channel estimate;
- a reconstruction unit configured to use the decoded data and the channel estimate to reconstruct encoded and modulated data samples;
- and
- a subtractor configured to subtract reconstructed data samples from the samples stored in the memory to reduce interference for the decoder to subsequently decode data for other access terminals from the stored samples.
5 more elements
A method comprising:
- receiving data samples of signals transmitted from a plurality of access terminals;
- despreading the received data samples with pilot chips associated with a first access terminal;
- demodulating the despread data samples into data symbols;
- decoding the demodulated data symbols;
- determining whether the demodulated data symbols were correctly decoded;
- if the demodulated data symbols were correctly decoded, using the decoded, demodulated data symbols to regenerate data chips transmitted by the first access terminal;
- based on estimated multipath signal delays, determining a time span for uniform regeneration;
- and
- despreading the received data samples with the regenerated, transmitted data chips at uniform delays for the determined time span to determine a channel estimate.
6 more elements
An apparatus comprising:
- means for receiving data samples of signals transmitted from a plurality of access terminals;
- means for despreading the received data samples with pilot chips associated with a first access terminal;
- means for demodulating the despread data samples into data symbols;
- means for decoding the demodulated data symbols;
- means for determining whether the demodulated data symbols were correctly decoded;
- if the demodulated data symbols were correctly decoded, means for using the decoded, demodulated data symbols to regenerate data chips transmitted by the first access terminal;
- based on estimated multipath signal delays, means for determining a time span for uniform regeneration;
- and
- means for despreading the received data samples with the regenerated, transmitted data chips at uniform delays for the determined time span to determine a channel estimate.
6 more elements
Dependencies are inferred from the claim text.