Abstract: Systems and methods for producing quality indicators for phase-based distance estimations using narrowband radios are described. In an illustrative, non-limiting embodiment, a device may include: a processor; and a memory coupled to the processor, the memory having program instructions stored thereon that, upon execution by the processor, cause the device to: measure a transfer function of a radio frequency (RF) channel between the device and another device using narrowband radios; estimate a distance between the device and the other device based, at least in part, upon the transfer function; and determine a Distance Quality Indicator (DQI) corresponding to the distance based, at least in part, upon an evaluation of a spectral lobe of the transfer function.

Abstract: A communication exchange between two wireless communication devices is monitored. A communication device configured to function as a Sniffer device synchronizes the communication device to a frequency and a timing employed between the two wireless communication devices on a main wireless communication channel. The wireless communication exchanges are monitored, in which the wireless communication exchanges are packet-based data exchanges or tone-based data exchanges. The operations for wireless communication exchanges are repeated across a plurality of different frequencies. The communication device then combines a plurality of phase and/or magnitude measurements and determines a value of phase and/or magnitude error introduced by each device based on the combined plurality of phase and/or magnitude measurements.

Abstract: A method for cartesian (IQ) to polar phase conversion includes: converting a first input value into a first absolute value, and a second input value into a second absolute value; converting the first absolute value into a first logarithmic value by calculating a scaled logarithmic value of the first absolute value, and the second absolute value into a second logarithmic value by calculating a scaled logarithmic value of the second absolute value; subtracting the first logarithmic value from the second logarithmic value, to provide a subtract value; and selecting a phase value from a plurality of phase values stored in a storage unit. Each of the plurality of phase values corresponds to a respective index value, and the phase value is selected taking the subtract value as the index value.

Abstract: Disclosed is a method of operating a low power wireless receiver in which a radio is periodically operable for receive intervals with sleep intervals therebetween and comprising a sleep clock having a sleep clock accuracy. A first transmission or packet is received. Based on a start moment of the first received packet, and an expected interval between packets, a nominal start moment is determined to start the radio for a packet window until a nominal end moment, for receiving a second packet; the packet window duration is extended in dependence on an estimated drift based on the SCA to provide a widened window. A start moment of a second received packet is measured within the widened window. An actual drift is calculated, from the start moment of the second packet; and an actual start moment and an actual window duration is determined, for receiving a third packet, based on the actual drift.

Abstract: A system for providing an enhanced acknowledgement (ENH-ACK) frame is configured to receive an incoming packet transmitted by an external device, determine that an ENH-ACK response is required based on a MAC header of the incoming packet schedule transmission of the ENH-ACK frame to the external device in accordance with a standard turnaround time limit relative to receipt of the incoming packet, determine contents of one or more packet processed fields of the ENH-ACK frame and populate the one or more packet processed fields, and complete transmission of the ENH-ACK frame with the populated packet processed fields.

Abstract: A wireless communication system including a radio, a processing circuit including a processor and wake on radio circuitry. The wake on radio circuitry uses programmed descriptors to autonomously schedule transitioning into and out of sleep mode to periodically awaken and turn on the radio and perform at least one radio frequency deterministic function while the processor remains in a low power state. The deterministic functions may include a receive function, a transmit function, or a combination of both. The descriptors may be programmed according to any one of different scheduling modes supported by different communication protocols including a timeslot mode and a constant-interval mode. The wake on radio circuitry includes a scheduler that coordinates with protocol circuitry of the radio for performing one or more deterministic functions. The scheduler may program a sleep controller for scheduling sleep modes between communication sessions for performing the deterministic functions.

Abstract: Securing protocol keys in a communication node comprises transferring a protocol access key stored in a secure enclave of a secure host platform to a secure key store in a communication platform via a secure transfer. The protocol access key which is plaintext is secure from access by a host processor of the secure host platform. A protocol key stored in the secure enclave is encrypted to an encrypted protocol key. The encrypted protocol key is transferred from the secure enclave to the communication platform over an unsecure bus. The encrypted protocol key is deciphered based on the protocol access key in the communication platform to form the protocol key. The protocol key which is plaintext is secured from access by the host processor, the communication controller, or both.

Abstract: A method for cartesian (IQ) to polar phase conversion includes: converting a first input value into a first absolute value, and a second input value into a second absolute value; converting the first absolute value into a first logarithmic value by calculating a scaled logarithmic value of the first absolute value, and the second absolute value into a second logarithmic value by calculating a scaled logarithmic value of the second absolute value; subtracting the first logarithmic value from the second logarithmic value, to provide a subtract value; and selecting a phase value from a plurality of phase values stored in a storage unit. Each of the plurality of phase values corresponds to a respective index value, and the phase value is selected taking the subtract value as the index value.

Abstract: A receiver path circuit includes a first stage, a down-sampler and a second stage. The first stage is configured to filter a mixer-output-signal received from a mixer and provide a first-stage-output-signal. The down-sampler is configured to down-sample the first-stage-output-signal to provide a transition-signal having a transition-frequency. The transition-frequency is lower than the frequency of the first-stage-output-signal. The second stage includes a switched-capacitor circuit that is configured to filter and reduce the frequency of the transition-signal in order to provide a second-stage-output-signal to an ADC.

Abstract: A type I phase locked loop (PLL) includes an oscillator and a feedback path to a phase detector. The PLL is configured to lock a first frequency and first relative phase of a first output signal to a frequency and a phase of a first input signal, and lock a second frequency and second relative phase of a second output signal to a frequency and a phase of a second input signal. A steady state phase lag of the PLL resulting from the difference between the first frequency and the second frequency is estimated, and the estimated steady state phase lag is used to determine a total phase shift (??LO,steady) between the second input signal and the second output signal. The PLL for the phase shift can be compensated. The determined total phase shift can be used in a distance estimation.

Abstract: A wireless communication system (100) estimates a carrier frequency offset between wireless devices (101, 102) by configuring the devices through exchanging packet configuration packets (121, 125) to specify a carrier frequency offset fingerprint (CFOF) sequence in a measurement packet (133, 136) which is transmitted between the wireless devices, where the CFOF sequence in the measurement packet includes a prefix component (31), one or more signature segments (32), and a suffix component (33) for performing CFO measurements at the wireless devices which each process IQ samples corresponding to the signature segments in the received measurement packet by correlating the IQ samples against a reference vector to generate, for each of the one or more signature segments, a carrier frequency offset estimate between the first and second wireless devices.

Abstract: A type I phase locked loop (PLL) includes an oscillator and a feedback path to a phase detector. The PLL is configured to lock a first frequency and first relative phase of a first output signal to a frequency and a phase of a first input signal, and lock a second frequency and second relative phase of a second output signal to a frequency and a phase of a second input signal. A steady state phase lag of the PLL resulting from the difference between the first frequency and the second frequency is estimated, and the estimated steady state phase lag is used to determine a total phase shift (??LO,steady) between the second input signal and the second output signal. The PLL for the phase shift can be compensated. The determined total phase shift can be used in a distance estimation.

Abstract: A type I phase locked loop (PLL) includes an oscillator and a feedback path to a phase detector. A first frequency and first relative phase of a first output signal are locked to a frequency and a phase of a first input signal. A second frequency and second relative phase of a second output signal are locked to a frequency and a phase of a second input signal. A correction to the PLL is applied to perform one of: adjusting the second relative phase to equal the first relative phase and adjusting the oscillator frequency.

Abstract: Disclosed is a method of operating a low power wireless receiver in which a radio is periodically operable for receive intervals with sleep intervals therebetween and comprising a sleep clock having a sleep clock accuracy. A first transmission or packet is received. Based on a start moment of the first received packet, and an expected interval between packets, a nominal start moment is determined to start the radio for a packet window until a nominal end moment, for receiving a second packet; the packet window duration is extended in dependence on an estimated drift based on the SCA to provide a widened window. A start moment of a second received packet is measured within the widened window. An actual drift is calculated, from the start moment of the second packet; and an actual start moment and an actual window duration is determined, for receiving a third packet, based on the actual drift.

Abstract: Embodiments are directed to monitoring network traffic over a network using one or more network monitoring computers. A monitoring engine may be instantiated to perform actions, including: monitoring network traffic to identify client requests provided by clients and server responses provided by servers in response to the client requests; determining request metrics associated with the client requests; and determining response metrics associated with the server responses. An analysis engine may be instantiated that performs actions, including: comparing the request metrics with the response metrics; determining atypical behavior associated with the clients based on the comparison such that the atypical behavior includes an absence of adaption by the clients to changes in the server responses; and providing alerts that may identify the clients be associated with the atypical behavior.

Abstract: A wireless communication system including a radio, a processing circuit including a processor and wake on radio circuitry. The wake on radio circuitry uses programmed descriptors to autonomously schedule transitioning into and out of sleep mode to periodically awaken and turn on the radio and perform at least one radio frequency deterministic function while the processor remains in a low power state. The deterministic functions may include a receive function, a transmit function, or a combination of both. The descriptors may be programmed according to any one of different scheduling modes supported by different communication protocols including a timeslot mode and a constant-interval mode. The wake on radio circuitry includes a scheduler that coordinates with protocol circuitry of the radio for performing one or more deterministic functions. The scheduler may program a sleep controller for scheduling sleep modes between communication sessions for performing the deterministic functions.

Abstract: A wireless ranging system (700) estimates a distance (703) between wireless devices (701, 702) by calibrating the devices through exchanging calibration packets (512, 524) to adjust transceiver settings for performing phase measurements at the wireless devices, and then transmitting a measurement packet (704) from a first wireless device to a second wireless device to synchronize the first and second wireless devices and to perform a two-way IQ data capture sequence at different carrier frequencies during processing of the measurement packet so that the first and second wireless devices each measure phase values for each of the plurality of different carrier frequencies, where the phase values at each of the first and second wireless devices are processed to generate a combined phase offset vector which is processed to determine a first estimated distance between the first and second wireless devices.

Abstract: A system for providing an enhanced acknowledgement (ENH-ACK) frame is configured to receive an incoming packet transmitted by an external device, determine that an ENH-ACK response is required based on a MAC header of the incoming packet schedule transmission of the ENH-ACK frame to the external device in accordance with a standard turnaround time limit relative to receipt of the incoming packet, determine contents of one or more packet processed fields of the ENH-ACK frame and populate the one or more packet processed fields, and complete transmission of the ENH-ACK frame with the populated packet processed fields.

Abstract: A wireless ranging system (700) estimates a distance (703) between wireless devices (701, 702) by calibrating the devices through exchanging calibration packets (512, 524) to adjust transceiver settings for performing phase measurements at the wireless devices, and then transmitting a measurement packet (704) from a first wireless device to a second wireless device to synchronize the first and second wireless devices and to perform a two-way IQ data capture sequence at different carrier frequencies during processing of the measurement packet so that the first and second wireless devices each measure phase values for each of the plurality of different carrier frequencies, where the phase values at each of the first and second wireless devices are processed to generate a combined phase offset vector which is processed to determine a first estimated distance between the first and second wireless devices.

Abstract: A wireless ranging system employs interference tolerance parameters in to reduce the effects of wireless interference on device performance (e.g. power consumption). As part of a wireless ranging session, each device identifies one or more wireless ranging parameters that indicate one or more limits (e.g. time limits, sample limits, and the like) corresponding to different portions of the ranging session. In response to a limit indicated by the interference tolerance parameters being reached prior to completion of the wireless ranging session, the wireless ranging system can take remedial action.