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US 8,335,283 B1Granted
Weak signal detection in wireless communication systems
AssigneeQualcomm Atheros, Inc.
InventorQinfang Sun
Life of this patent
Estimating the term…
Abstract
A mechanism for weak signal packet detection in a wireless receiver. Cross-correlation and self-correlation operations are performed on a plurality of short training field symbols associated with a plurality of RF signals received at a plurality of receiver chains of the wireless receiver. A plurality of self-correlation outputs generated in the plurality of receiver chains are summed and the sum of the self-correlation outputs is accumulated over a predetermined number of STF symbol periods. A moving sum operation is performed on the accumulation output when the accumulation output is greater than a first predetermined threshold. A signal indicating a data packet has been detected is generated when the moving sum output is greater than a second predetermined threshold.
Claims17
A method for implementing weak signal packet detection comprising:
- performing cross-correlation and self-correlation operations on a plurality of short training field (STF) symbols associated with a plurality of RF signals received at a plurality of receiver chains of a wireless receiver;
- summing a plurality of self-correlation outputs generated in the plurality of receiver chains;
- weighting the sum of the self-correlation outputs, wherein said weighting the sum of the self-correlation outputs comprises:
- calculating a power of the plurality of STF symbols associated with the plurality of RF signals received at the plurality of receiver chains;
- summing the calculated power outputs generated in the plurality of receiver chains;
- and
- dividing the sum of the self-correlation outputs by the sum of the calculated power outputs;
- accumulating the weighted sum of the self-correlation outputs over a predetermined number of STF symbol periods;
- performing a moving sum operation on the accumulation output when the accumulation output is greater than a first predetermined threshold;
- and
- generating a signal indicating a data packet has been detected when the moving sum output is greater than a second predetermined threshold.
8 more elements
A wireless receiver comprising:
- a plurality of receiver chains operable to receive a plurality of RF signals, wherein each of the receiver chains comprises a cross-correlation unit coupled to a self-correlation unit, wherein the cross-correlation units and the self-correlation units are operable to perform cross-correlation and self-correlation operations, respectively, on a plurality of short training field (STF) symbols associated with the plurality of received RF signals;
- a first summing unit operable to sum outputs of the self-correlation units in the plurality of receiver chains;
- a weighting unit operable to weight the output of the first summing unit to generate a weighted sum of the outputs of the self-correlation units, wherein the weighting unit operable to weight the sum of the self-correlation outputs comprises,
- a power unit of each of the plurality of receiver chains operable to calculate a power of each of the STF symbols received at the receiver chain;
- a second summing unit operable to sum outputs of the power units in the plurality of receiver chains;
- and
- the weighting unit operable to divide the sum of the outputs of the self-correlation units by the sum of the outputs of the power units to generate the weighted sum of the outputs of the self-correlation units;
- an accumulation unit operable to accumulate the weighted sum of the outputs of the self-correlation units at the output of the weighting unit over a predetermined number of STF symbol periods;
- a moving sum unit operable to perform a moving sum operation on an output of the accumulation unit when the output of the accumulation unit is greater than a first predetermined threshold;
- and
- a detection unit operable to generate a signal indicating a data packet has been detected when an output of the moving sum unit is greater than a second predetermined threshold.
8 more elements
One or more non-transitory machine-readable storage media having instructions stored therein, which when executed by one or more processors causes the one or more processors to perform operations that comprise:
- performing cross-correlation and self-correlation operations on a plurality of short training field (STF) symbols associated with a plurality of RF signals received at a plurality of receiver chains of a wireless receiver;
- summing a plurality of self-correlation outputs generated in the plurality of receiver chains;
- weighting the sum of the self-correlation outputs, wherein said weighting the sum of the self-correlation outputs comprises:
- calculating a power of the plurality of STF symbols associated with the plurality of RF signals received at the plurality of receiver chains;
- summing the calculated power outputs generated in the plurality of receiver chains;
- and
- dividing the sum of the self-correlation outputs by the sum of the calculated power outputs;
- accumulating the weighted sum of the self-correlation outputs over a predetermined number of STF symbol periods;
- performing a moving sum operation on the accumulation output when the accumulation output is greater than a first predetermined threshold;
- and
- generating a signal indicating a data packet has been detected when the moving sum output is greater than a second predetermined threshold.
8 more elements
A wireless local area (WLAN) device comprising:
- a transmitter operable to transmit RF signals via a network;
- and
- a receiver coupled to the transmitter and operable to receive RF signals via the network, wherein the receiver comprises:
- a plurality of receiver chains operable to receive a plurality of RF signals, wherein each of the receiver chains comprises a cross-correlation unit coupled to a self-correlation unit, wherein the cross-correlation units and the self-correlation units are operable to perform cross-correlation and self-correlation operations, respectively, on a plurality of short training field (STF) symbols associated with the plurality of received RF signals;
- a first summing unit operable to sum outputs of the self-correlation units in the plurality of receiver chains;
- a weighting unit operable to weight the output of the first summing unit to generate a weighted sum of the outputs of the self-correlation units, wherein the weighting unit operable to weight the sum of the self-correlation outputs comprises,
- a power unit of each of the plurality of receiver chains operable to calculate a power of each of the STF symbols received at the receiver chain;
- a second summing unit operable to sum outputs of the power units in the plurality of receiver chains;
- and
- the weighting unit operable to divide the sum of the outputs of the self-correlation units by the sum of the outputs of the power units to generate the weighted sum of the outputs of the self-correlation units;
- an accumulation unit operable to accumulate the weighted sum of the outputs of the self-correlation units at output of the weighting unit over a predetermined number of STF symbol periods;
- a moving sum unit operable to perform a moving sum operation on an output of the accumulation unit when the output of the accumulation unit is greater than a first predetermined threshold;
- a detection unit operable to generate a signal indicating a data packet has been detected when an output of the moving sum unit is greater than a second predetermined threshold.
10 more elements
Dependencies are inferred from the claim text.