Abstract: A system includes a transceiver and an access module. The transceiver is implemented at a vehicle: receives a first RF signal from a portable access device via multiple antennas; transmits a second RF signal from the vehicle to the portable access device; and receives a third RF signal from the portable access device. The third RF signal indicates an AOD of the first RF signal or a second AOA of the second RF signal as received at the portable access device. The access module: estimates a first AOA of the first RF signal; determines a resultant AOA based on the first AOA and the AOD or the second AOA; determines a location of the portable access device relative to the vehicle based on the resultant AOA; and permits access to the vehicle or control of a portion of the vehicle based on the location of the portable access device.

Abstract: A method and system of creating microlocation zones by defining virtual boundaries using a system of one or more transmitters and receivers with one or more spatially-correlated antennas.

Abstract: A system and method are disclosed and include receiving a wireless signal. The method includes generating a first and second set of digital data that are representative of the wireless signal. The method includes obtaining a first and second sample that is representative of a cosine and sine component, respectively, of a pre-known portion of the first set. The method includes obtaining a third and fourth sample that is representative of a cosine and sine component, respectively, of a pre-known portion of the second set. The method includes determining a first phase angle value based on an amplitude of the first and second samples and a second phase angle based on an amplitude of the third and fourth samples. The method includes determining an angle of arrival based on a difference between the first and second phase angle values.

Abstract: An access system for a vehicle is provided. The access system includes antennas and an access module. The antennas are configured to each receive a signal transmitted from a portable access device to the vehicle. The signal is transmitted on a 2.4 gigahertz frequency. The access module is configured to: downconvert the received signal to generate an in-phase signal and a quadrature phase signal; perform carrier phase based ranging including implementing a music algorithm to (i) determine a distance between the portable access device and the vehicle, and (ii) determine angles of arrival of the received signal as received at the antennas; determine a location of the portable access device relative to the vehicle based on the distance and the angles of arrival; and permit access to the vehicle based on the location.

Abstract: A feed circuit for feeding an antenna includes: a first coupler including a first pair of opposing conductive elements; a second coupler including a second pair of opposing conductive elements; a third coupler including a third pair of opposing conductive elements; a delay line; first terminals configured to connect to the antenna; second terminals connected to a ground reference; and a feed terminal connected to the first coupler and configured to receive at least one of a transmit signal to be transmitted from the antenna or a combined received signal from the antenna. The first terminals are connected to the second coupler and the third coupler and configured to output a signal at different phases to conductive elements of the antenna. The second terminals are connected to the first coupler, the second coupler and the third coupler.

Abstract: An access system for a vehicle is provided and includes antennas and an access module. The antennas are configured to each receive a signal transmitted from a portable access device to the vehicle. One of the antennas is a circular polarized antenna. The access module is configured to: downconvert the received signal to generate an in-phase signal and a quadrature phase signal; execute a music algorithm to determine angles of arrival of the received signal as received at the antennas; determine a distance between the portable access device and the vehicle based on the angles of arrival; and permit access to the vehicle based on the distance.

Abstract: A communication system with a master device configured to determine location information in real-time with respect to a portable device. The master device may direct one or more monitor devices to monitor communications that occur over a primary communication link. The monitor devices may sense characteristic information about the signal from the portable device, and communicate this characteristic information to the master device via an auxiliary communication link. The communication system may determine location of the portable device, authenticate the portable device, determine whether the portable device is authorized to allow or initiate an action, and command or enable an action with respect to equipment.

Abstract: A method and system of creating microlocation zones by defining virtual boundaries using a system of one or more transmitters and receivers with one or more spatially-correlated antennas.

Abstract: Methods and systems are disclosed and include receiving a signal via a first communication channel at a plurality of azimuth angles. The method includes determining a plurality of first communication channel phase angle differences between a pair of antennas. The method includes receiving a second signal via a second communication channel and at the plurality of azimuth angles. The method includes determining a plurality of second communication channel phase angle differences between the pair of antennas that each correspond to one of the plurality of azimuth angles. The method includes generating a first reference curve based on the plurality of first communication channel phase angle differences. The method includes generating a second reference curve based on the plurality of second communication channel phase angle differences. The method also includes generating a calibration curve that is based on an interpolation of the first reference curve and the second reference curve.

Abstract: A method of communicating with a portable access device includes iteratively performing an algorithm via an access module of a vehicle. The algorithm includes a series of operations including: selecting a frequency from multiple frequencies; selecting an antenna pair from multiple possible antenna pairs, where antennas of the possible antenna pairs include antennas with different polarized axes; transmitting a packet to the portable access device via the selected antenna pair; receiving a first RSSI and a response signal from the portable access device, the first RSSI corresponds to the transmission of the packet; and measuring a second RSSI of the response signal; based on the first RSSIs and the second RSSIs. A best one of the frequencies and a best antenna pair of the possible antenna pairs are selected. One or more additional packets are transmitted using the selected best frequency and the selected best antenna pair.

Abstract: Methods and systems are disclosed and include receiving, at a plurality of azimuth angles, a signal via a first communication channel and a second signal via a second communication channel. The method includes determining a plurality of first and second communication channel phase angle differences of the antenna system that each correspond to one of the plurality of azimuth angles. The method includes generating a first reference curve and a second reference curve based on the plurality of first and second communication channel phase angle differences, respectively. The method includes determining a first set and a second set of phase difference limits, and for each set, the method includes: identifying a minimum and maximum capping region; determining a minimum phase difference limit based on a central location of the minimum capping region; and determining a maximum phase difference limit based on a central location of the maximum capping region.

Abstract: A system includes a transceiver and an access module. The transceiver is implemented at a vehicle: receives a first RF signal from a portable access device via multiple antennas; transmits a second RF signal from the vehicle to the portable access device; and receives a third RF signal from the portable access device. The third RF signal indicates an AOD of the first RF signal or a second AOA of the second RF signal as received at the portable access device. The access module: estimates a first AOA of the first RF signal; determines a resultant AOA based on the first AOA and the AOD or the second AOA; determines a location of the portable access device relative to the vehicle based on the resultant AOA; and permits access to the vehicle or control of a portion of the vehicle based on the location of the portable access device.

Abstract: A communication system with a master device configured to determine location information in real-time with respect to a portable device. The master device may direct one or more monitor devices to monitor communications that occur over a primary communication link. The monitor devices may sense characteristic information about the signal from the portable device, and communicate this characteristic information to the master device via an auxiliary communication link. The communication system may determine location of the portable device, authenticate the portable device, determine whether the portable device is authorized to allow or initiate an action, and command or enable an action with respect to equipment.

Abstract: Systems and methods are disclosed and include receiving, with a peripheral device, a message packet from a portable device, the message packet including an authenticated packet with a de-whitened tone byte inserted therein. The portable device generates first message authentication code (MAC) bytes based on a shared secret key and generates the authenticated packet based on the first MAC bytes, first nonce bytes, and a message byte. The peripheral device validates the message packet in response to determining that the first MAC bytes match second MAC bytes and that the first nonce bytes match second nonce bytes. The peripheral device generates a reconstructed message packet in response to validating the message packet by removing the de-whitened tone byte from the authenticated packet. The communication gateway establishes a communication link between the portable device and the communication gateway in response to receiving the reconstructed message packet.

Abstract: A system for detecting a range extension type relay attack includes a transmitter, a receiver and a module. The transmitter transmits a RF signal from one of a vehicle and a portable access device to the other one of the vehicle and the portable access device. The receiver receives a response signal in response to the RF signal. The module: generates a parameter associated with the transmission of the RF signal and the reception of the response signal; based on the parameter, detects the range extension type relay attack performed by an attacking device, where at least one of (i) the RF signal is relayed via the attacking device from the vehicle to the portable access device, or (ii) the response signal is relayed via the attacking device from the portable access device to the vehicle; and perform a countermeasure in response to detecting the range extension type relay attack.

Abstract: A system for includes master and sniffer devices. The master device includes: first antennas with different polarized axes; a transmitter transmitting a challenge signal via the first antennas from the vehicle to a slave device, where the slave device is a portable access device; and a receiver receiving a response signal in response to the challenge signal from the slave device. The sniffer device includes: second antennas with different polarized axes; and a receiver receiving, via the second antennas, the challenge signal from the transmitter and the response signal from the slave device. The sniffer device measures when the challenge signal and the response signal arrive at the sniffer device to provide arrival times. The master or sniffer device estimates at least one of a distance from the vehicle to the slave device or a location of the slave device relative to the vehicle based on the arrival times.

Abstract: A system includes a transmitter, a receiver and a control module. The transmitter transmits a RF signal from one of a vehicle and a portable access device to the other one of the vehicle and the portable access device. The receiver receives a response signal from one of the vehicle and the portable access device in response to the RF signal. The control module: converts the response signal to in-phase and quadrature-phase signals; based on the RF, in-phase signal and quadrature-phase signals; detects a range extension type relay attack performed by an attacking device to obtain at least one of access to or operational control of the vehicle; where the RF signal is relayed via the attacking device from the vehicle to the portable access device or the response signal is relayed via the attacking device from the portable access device to the vehicle; and performs a countermeasure.

Abstract: A multi-axis polarized RF antenna assembly includes a circular polarized antenna, a circular isolator, and a linear polarized antenna. The circular polarized antenna includes a conductive ring-shaped body having an inner hole. The circular isolator is connected to the conductive ring-shaped body. The linear polarized antenna is connected to the circular polarized antenna and the circular isolator and extending outward from the circular isolator. The linear polarized antenna includes a sleeve and a conductive element extending through the sleeve. The linear polarize antenna extends orthogonal to a radius of the circular polarized antenna.

Abstract: A system for accessing or providing operational control of a vehicle includes initiator and sniffer devices. The initiator device includes: polarized antennas; a transmitter transmitting a first tone signal via the polarized antennas from the vehicle to a responder/portable access device; and receiver receiving a second tone signal from the responder device in response to the first tone signal. The sniffer device includes: second polarized antennas; and a second receiver receiving, via the second polarized antennas, the first tone signal from the transmitter and the second tone signal from the responder device. The sniffer device determines states of the first and second tone signals including respective phase delays. The initiator or sniffer device estimates a first distance from the vehicle to the responder device or a second distance from the responder device to the sniffer device based on the states including respective phase delays.

Abstract: A method and apparatus includes a processor that receives information corresponding to a first signal strength of a communication link between a remote device and a communication gateway of a vehicle. The information corresponding to the first signal strength is associated with a first antenna of a sensor and the first antenna includes a first peak main lobe magnitude oriented in a first direction. The processor also receives information corresponding to a second signal strength of the communication link. The information corresponding to the second signal strength is associated with a second antenna. The second antenna includes a second peak main lobe magnitude oriented in a second direction. The processor executes a first boundary line determination that includes determining whether the remote device is located on a first side of a boundary line based on the first signal strength and the second signal strength.