Cross-correlation suppression technique for position location receivers
AssigneeQUALCOMM Incorporated
InventorPeter Gaal
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Abstract
The present disclosure provides various methods and devices for suppressing cross-correlation effects in positioning signals. When there is a power imbalance between a weaker positioning signal and an interfering positioning signal, and certain Doppler offsets exist, cross-correlation may make it difficult to acquire the weaker signal. However, a receiver may use the transmit signal spectrum of the interfering signal to identify frequency bins which contain a lower power for the transmitted interfering signal. The receiver then emphasizes the identified frequency bins in the detection of the desired positioning signal.
Claims42
A method of reducing impact of cross-correlation in a desired positioning signal, the method comprising:
- correlating a plurality of received positioning signals with a reference code of the desired positioning signal to produce a correlated output;
- processing power spectra of an interfering signal of the plurality to identify a first set of one or more frequency bins where the interfering signal is weak relative to a second set of frequency bins of the power spectra;
- and
- allocating a proportionally greater weight to the identified first set of frequency bins than the second set when measuring the correlated output.
A mobile station configured to reduce impact of cross-correlation in a desired positioning signal, the mobile station comprising:
- an antenna configured to receive a plurality of positioning signals;
- a first processing unit coupled with the antenna, and configured to:
- correlate the plurality of received positioning signals with a reference code of the desired positioning signal to produce a correlated output;
- process power spectra of an interfering signal of the plurality to identify a first set of one or more frequency bins where the interfering signal is weak relative to a second set of frequency bins of the power spectra;
- and
- allocate a proportionally greater weight to the identified first set of frequency bins than the second set when measuring the correlated output;
- and
- a memory coupled with the processor.
A communications device configured to reduce impact of cross-correlation in a desired positioning signal, the device comprising:
- means for receiving a plurality of positioning signals;
- means for correlating the plurality of received positioning signals with a reference code of the desired positioning signal to produce a correlated output;
- means for processing power spectra of an interfering signal of the plurality to identify a first set of one or more frequency bins where the interfering signal is weak relative to a second set of frequency bins of the power spectra;
- and
- means for allocating a proportionally greater weight to the identified first set of frequency bins than the second set when measuring the correlated output.
A computer-readable medium tangibly embodying computer-executable instructions configured to reduce impact of cross-correlation in a desired positioning signal, the computer-readable medium comprising computer-executable instructions for:
- correlating a plurality of received positioning signals with a reference code of the desired positioning signal to produce a correlated output;
- processing power spectra of an interfering signal of the plurality to identify a first set of one or more frequency bins where the interfering signal is weak relative to a second set of frequency bins of the power spectra;
- and
- allocating a proportionally greater weight to the identified first set of frequency bins than the second set when measuring the correlated output.
A processor configured to reduce impact of cross-correlation in a desired positioning signal, the processor configured to:
- correlate the plurality of received positioning signals with a reference code of the desired positioning signal to produce a correlated output;
- process power spectra of an interfering signal of the plurality to identify a first set of one or more frequency bins where the interfering signal is weak relative to a second set of frequency bins of the power spectra;
- and
- allocate a proportionally greater weight to the identified first set of frequency bins than the second set when measuring the correlated output.
A positioning system configured to reduce impact of cross-correlation in a desired positioning signal, the system comprising:
- a plurality of transmitters each configured to transmit positioning signals to a mobile station, including:
- a first transmitter of the plurality transmitting a desired positioning signal;
- and
- a second transmitter of the plurality transmitting an interfering signal and data comprising signal parameters related to the interfering signal;
- a base station communicatively coupled with the second transmitter, and configured to transmit the data received from the second transmitter to the mobile station;
- and
- the mobile station, communicatively coupled with the plurality of transmitters and the base station, the mobile station configured to:
- receive the positioning signals from the plurality of transmitters, including the desired positioning signal and the interfering signals;
- correlate the plurality of received positioning signals with a reference code of the desired positioning signal to produce a correlated output;
- receive the data transmitted from the base station;
- calculate power spectra of the interfering signal based at least in part on the received data, to thereby identify a first set of one or more frequency bins where the interfering signal is weak relative to a second set of frequency bins of the power spectra;
- and
- allocate a proportionally greater weight to the identified first set of frequency bins than the second set when measuring the correlated output.
Dependencies are inferred from the claim text.