Abstract: A method and apparatus for measuring the angle of arrival AOA of Wi-Fi packets, using a switched beam antenna SBA is described. Wide antenna beams, quadrants, are selected in turn and a burst of packets is transmitted on each quadrant. The quadrant with the highest average signals strength is selected. Then the narrow antenna beams that make up that selected quadrant are selected, in sequence, and the average signal strength for each narrow beam is recorded. The narrow beam with the highest average signal strength is returned as the AOA. Based upon which narrow beam recorded the highest signal strength, the next sequence of antenna beams is selected. When the SBA is mounted on a mobile platform, the parameters of the transmission bursts are chosen such that the angular error due to cornering of the platform is negligible.

Abstract: A method and apparatus for measuring confidence in the angle of arrival AOA of Wi-Fi packets, from a target station, using a switched beam antenna SBA is described. AOAs can be inaccurate due to reflections and multipaths. To assess the confidence of an AOA, each AOA is first converted to relative north, AOAt, and checked that at least M AOAs have been received in time T. If so, the standard deviation is calculated for of all the AOAs received during previous time T. If the standard deviation is less than a preset value, and the receiving station is not stationary, then the AOAt is considered to have high confidence and may be used to calculate the target station location. A vector display of the AOA uses the standard deviation to display the AOA vector as a varying length or a varying beamwidth corresponding to the standard deviation.

Abstract: A method and apparatus for measuring confidence in the angle of arrival AOA of Wi-Fi packets, from a target station, using a switched beam antenna SBA is described. AOAs can be inaccurate due to reflections and multipaths. To assess the confidence of an AOA, each AOA is first converted to relative north, AOAt, and checked that at least M AOAs have been received in time T. If so, the standard deviation is calculated for of all the AOAs received during previous time T. If the standard deviation is less than a preset value, and the receiving station is not stationary, then the AOAt is considered to have high confidence and may be used to calculate the target station location. A vector display of the AOA uses the standard deviation to display the AOA vector as a varying length or a varying beamwidth corresponding to the standard deviation.

Abstract: A method and apparatus for measuring the angle of arrival AOA of Classic Bluetooth Basic Rate (BR) packets, using a switched beam antenna SBA is described. Paging packets are transmitted and wide antenna beams, quadrants, are selected in turn until the paging response is received. After transmitting the synchronization packet and the temporary connection is established, narrow antenna beams are selected, in sequences and the average signal strength for each beam is recorded, for each sequence. The beam with the highest signal strength is returned as the AOA. Based upon which beam recorded the highest signal strength, the next sequence of antenna beams is selected.

Abstract: A method and apparatus for measuring the angle of arrival AOA of Wi-Fi packets, using a switched beam antenna SBA is described. Wide antenna beams, quadrants, are selected in turn and a burst of packets is transmitted on each quadrant. The quadrant with the highest average signals strength is selected. Then the narrow antenna beams that make up that selected quadrant are selected, in sequence, and the average signal strength for each narrow beam is recorded. The narrow beam with the highest average signal strength is returned as the AOA. Based upon which narrow beam recorded the highest signal strength, the next sequence of antenna beams is selected. When the SBA is mounted on a mobile platform, the parameters of the transmission bursts are chosen such that the angular error due to cornering of the platform is negligible.

Abstract: A method and apparatus for measuring the angle of arrival AOA of Classic Bluetooth Basic Rate (BR) packets, using a switched beam antenna SBA is described. Paging packets are transmitted and wide antenna beams, quadrants, are selected in turn until the paging response is received. After transmitting the synchronization packet and the temporary connection is established, narrow antenna beams are selected, in sequences and the average signal strength for each beam is recorded, for each sequence. The beam with the highest signal strength is returned as the AOA. Based upon which beam recorded the highest signal strength, the next sequence of antenna beams is selected.

Abstract: A method and apparatus for measuring the angle of arrival AOA of Wi-Fi packets, using a switched beam antenna SBA is described. Wide antenna beams, quadrants, are selected in turn and a burst of packets is transmitted on each quadrant. The quadrant with the highest average signals strength is selected. Then the narrow antenna beams that make up that selected quadrant are selected, in sequence, and the average signal strength for each narrow beam is recorded. The narrow beam with the highest average signal strength is returned as the AOA. Based upon which narrow beam recorded the highest signal strength, the next sequence of antenna beams is selected. When the SBA is mounted on a mobile platform, the parameters of the transmission bursts are chosen such that the angular error due to cornering of the platform is negligible.

Abstract: A method implemented in a monitoring station is described. The monitoring station is configurable to monitor a communication between a first wireless device and a second wireless device. The method includes receiving a packet from the first wireless device, the packet being addressed to the second wireless device and determining whether the received packet meets at least one criterion of one packet that is to be blocked. The method further includes transmitting a blocking signal when the received packet meets the at least one criterion of the one packet that is to be blocked. The blocking signal causes an interference with a reception, at the second wireless device, of at least one field of the received packet.

Abstract: A method in a wireless device (WD) is described. The method is at least for determining a geo-location of a target station using round-trip times (RTTs) of a plurality of signals transmitted by the WD and a plurality of response signals received from the target station corresponding to the plurality of signals transmitted by the WD. The method includes determining an expected response signal, and, for each transmitted signal of the plurality of signals, determining that a response signal type matches an expected response signal type, cross-correlating a set of samples of the response signal, searching for a predetermined characteristic of the expected response signal, and correlating at least a subset of bits of the set of bits of the received response signal with the set of expected bits of the expected response signal. Further, a peak rolling sum correlation and the RTTs are determined.

Abstract: A method in a first wireless device (WD) is described. The method includes determining a plurality of expected response signals, each having a scrambling seed number and an expected sequence of time domain symbols; receiving a plurality of response signals; determining a plurality of frequency shifted time domain samples, cross-correlating each frequency shifted time domain sample with the expected sequence of time domain symbols, for each scrambling seed number of each expected response signal; determining a maximum correlation value for each frequency shift and each frequency shifted time domain sample; summing the maximum correlation value for each frequency shift, each frequency shifted time domain sample, and each response signal; determining a peak correlation value based on the summed maximum correlation value; and determining at least the round trip time associated with the plurality of ranging signals based at least in part on the peak correlation value.

Abstract: A method in a wireless device (WD) is described. The method is at least for determining a geo-location of a target station using round-trip times (RTTs) of a plurality of signals transmitted by the WD and a plurality of response signals received from the target station corresponding to the plurality of signals transmitted by the WD. The method includes determining an expected response signal, and, for each transmitted signal of the plurality of signals, determining that a response signal type matches an expected response signal type, cross-correlating a set of samples of the response signal, searching for a predetermined characteristic of the expected response signal, and correlating at least a subset of bits of the set of bits of the received response signal with the set of expected bits of the expected response signal. Further, a peak rolling sum correlation and the RTTs are determined.

Abstract: A method in a monitoring station configured for communication with a wireless device is described. The method includes determining a round trip time, RTT, that corresponds to a first packet transmitted to the wireless device; receiving a second packet from the wireless device; determining the second packet from the wireless device has been received without error based at least in part on an error-detecting field; and receiving a subsequent packet from the wireless device. The method further includes determining that the subsequent packet received is a second packet retransmission; determining a preamble receipt time of the subsequent packet; determining a delay value based in part on the RTT of the first packet, the length field of the subsequent packet, and data rate field of the subsequent packet. The first acknowledgement packet is transmitted timed at the delay value after the preamble receipt time of the subsequent packet.

Abstract: A method and wireless devices (WDs) for geo-location of wireless devices are disclosed. According to one aspect, a method in a first WD includes: transmitting a sequence of ranging signals and receiving a plurality of ranging response signals from a second WD, the ranging response signals being responsive to the ranging signals. For each of the plurality of ranging response signals, a received sequence of bits is determined. A correlation between the received sequence of bits and an expected sequence of bits is determined. The method also includes determining a subset of the plurality of received sequences of bits deemed not to arise from noise, and determining the subset being based at least in part on the correlations. The method also includes determining a distance between the first WD and the second WD based at least in part on a plurality of received sequences in the subset.

Abstract: Methods and devices are disclosed that derive an IQ magnitude parameter, and then determine the optimum IQ magnitude for wanted signals with negative signal to noise values. For each device installation, a calibration routine may be carried out that sets the baseband gain to produce this optimum IQ magnitude for each frequency channel.

Abstract: A method in a first wireless device (WD) is described. The method includes determining a plurality of expected response signals, each having a scrambling seed number and an expected sequence of time domain symbols; receiving a plurality of response signals; determining a plurality of frequency shifted time domain samples, cross-correlating each frequency shifted time domain sample with the expected sequence of time domain symbols, for each scrambling seed number of each expected response signal; determining a maximum correlation value for each frequency shift and each frequency shifted time domain sample; summing the maximum correlation value for each frequency shift, each frequency shifted time domain sample, and each response signal; determining a peak correlation value based on the summed maximum correlation value; and determining at least the round trip time associated with the plurality of ranging signals based at least in part on the peak correlation value.

Abstract: A method in a first wireless device (WD) is described. The method includes determining a plurality of expected response signals, each having a scrambling seed number and an expected sequence of time domain symbols; receiving a plurality of response signals; determining a plurality of frequency shifted time domain samples, cross-correlating each frequency shifted time domain sample with the expected sequence of time domain symbols, for each scrambling seed number of each expected response signal; determining a maximum correlation value for each frequency shift and each frequency shifted time domain sample; summing the maximum correlation value for each frequency shift, each frequency shifted time domain sample, and each response signal; determining a peak correlation value based on the summed maximum correlation value; and determining at least the round trip time associated with the plurality of ranging signals based at least in part on the peak correlation value.

Abstract: A method in a wireless device (WD) is described. The method is at least for determining a geo-location of a target station using round-trip times (RTTs) of a plurality of signals transmitted by the WD and a plurality of response signals received from the target station corresponding to the plurality of signals transmitted by the WD. The method includes determining an expected response signal, and, for each transmitted signal of the plurality of signals, determining that a response signal type matches an expected response signal type, cross-correlating a set of samples of the response signal, searching for a predetermined characteristic of the expected response signal, and correlating at least a subset of bits of the set of bits of the received response signal with the set of expected bits of the expected response signal. Further, a peak rolling sum correlation and the RTTs are determined.

Abstract: A method in a monitoring station configured for communication with a wireless device is described. The method includes determining a round trip time, RTT, that corresponds to a first packet transmitted to the wireless device; receiving a second packet from the wireless device; determining the second packet from the wireless device has been received without error based at least in part on an error-detecting field; and receiving a subsequent packet from the wireless device. The method further includes determining that the subsequent packet received is a second packet retransmission; determining a preamble receipt time of the subsequent packet; determining a delay value based in part on the RTT of the first packet, the length field of the subsequent packet, and data rate field of the subsequent packet. The first acknowledgement packet is transmitted timed at the delay value after the preamble receipt time of the subsequent packet.

Abstract: A method and measuring station to determine the geo-location of a wanted target station in the presence of rogue responder stations are disclosed. One method includes: transmitting a packet with a fictitious address not corresponding to the wanted target station address; transmitting a packet with the wanted target station address; determining at least one of: a first difference between a round trip time (RTT) associated with a response packet from a responder station and an RTT associated with a response packet from the wanted target station; and a second difference between a time of arrival (TOA) associated with the responder station's response packet and a TOA associated with the wanted target station's response packet; and distinguishing between the response from the responder station and the response from the wanted target station based on at least at least one of the first difference and the second difference.

Abstract: A method and wireless devices (WDs) for geo-location of wireless devices are disclosed. According to one aspect, a method in a first WD includes: transmitting a sequence of ranging signals and receiving a plurality of ranging response signals from a second WD, the ranging response signals being responsive to the ranging signals. For each of the plurality of ranging response signals, a received sequence of bits is determined. A correlation between the received sequence of bits and an expected sequence of bits is determined. The method also includes determining a subset of the plurality of received sequences of bits deemed not to arise from noise, and determining the subset being based at least in part on the correlations. The method also includes determining a distance between the first WD and the second WD based at least in part on a plurality of received sequences in the subset.