Texas Instruments Corporation

Nxp Usa, Inc.

Freescale Semiconductor,inc.

Nxp B.v.

National Semiconductor Corporation

Khurram Waheed

Robert Bogdan Staszewski

Mihai-Ionut Stanciu

Kevin B Traylor

Raja Venkatesh Tamma

Sameh Sameer Rezeq

Sudheer Kumar Vemulapalli

John L Wallberg

Seydou Nourou Ba

Steven M Bosze

Chris N Stoll

Jingcheng Zhuang

Claudio Gustavo Rey

Mahbuba Sheba

Khurram Muhammad

Oren E Eliezer

Stefano Dal Toso

Mathieu Perin

Tim Foo

Yaoqiao Li

Carlos Alberto Neri Castellanos

Socrates Vamvakos

Jayson D Vogler

Jayawardan Janardhanan

Vijay Ahirwar

Siraj Akhtar

Saket Jalan

Karl F Nieman

Roman Staszewski

Jaimin A Mehta

Shobak R Kythakyapuzha

Imran Bashir

Jianqiang Zeng

Doru Cristian Gucea

Mathieu Périn

Ioan-Virgil Dragomir

Chris P Nappi

Sreenivasa Murthy Nerayanuru

Yongtao Wang

Keith A Tilley

Olivier Jean

Manouchehr Entezari

Yijie Zhang

Marius Preda

George R Redford

Jose Santiago Lopez Ramirez

Prachee S Behera

Prasad Srinivasan

Thomas Casimir Murphy

Mihai Ionut Stanciu

William S King

David F Brown

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.

Baseband receiver circuit

A transmit apparatus comprising a scaler arranged to scale a frequency deviation signal associated with a frequency shift keying signal (FSK) by a scale factor and a limiter arranged to limit frequency deviations of the scaled frequency deviation signal after a filtering. A power spectral density, phase trajectory, and frequency deviation of an FSK signal based on the limited scaled frequency deviation tracks similar criteria of a minimum phase shift keying (MSK) signal.

Transmit apparatus arranged to scale and limit frequency deviation generated after a filtering based on a frequency shift keying (FSK) signal and methods of operation

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.

Type-I PLLs for phase-controlled applications

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.

Communication node with secure cryptographic keys and methods for securing therein

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.

Distance quality indicator (DQI) for phase-based distance estimation using narrowband radios

A wireless communication system () estimates a carrier frequency offset between wireless devices () by configuring the devices through exchanging packet configuration packets () to specify a carrier frequency offset fingerprint (CFOF) sequence in a measurement packet () which is transmitted between the wireless devices, where the CFOF sequence in the measurement packet includes a prefix component (), one or more signature segments (), and a suffix component () 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.

Method and technique of highly accurate carrier frequency offset estimation

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.

IQ to phase conversion method and apparatus

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.

Method of receiver window widening and autodrift calculation using packet timestamping

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.

Autonomous wake on radio scheduler that schedules deterministic radio events to reduce involvement of primary processor

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.

System and method for providing an enhanced acknowledgement frame

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 (&#x394;&#x3a6;) 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.

A wireless ranging system () estimates a distance () between wireless devices () by calibrating the devices through exchanging calibration packets () to adjust transceiver settings for performing phase measurements at the wireless devices, and then transmitting a measurement packet () 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.

Method and technique of power-efficient two-way phase based distance estimation using packet synchronized data capture

A wireless ranging system generates, at a first device, a first plurality of counts, each of the first plurality of counts indicative of a transmit time of a corresponding packet, and further generates a second plurality of counts, each of the second plurality of counts indicative of a receive time of a corresponding packet. In response to a number of samples of the first plurality of counts exceeding a threshold, the system generates a plurality of timestamps based on the first plurality of counts and the second plurality of counts and generates a plurality of time-of-flight values based on the plurality of timestamps. Based on a combination of the plurality of the time-of-flight values, the wireless ranging system generates an effective time-of-flight value and identifies a distance between the first device and as second device based on the effective time-of-flight value.

Distance estimation based on narrow-band wireless time-of-flight

Disclosed is receiver apparatus including a first input configured to receive a first signal, a second input configured to receive a second signal, a switching circuit configured to alternate between the first and second signal from the first and second inputs, a receiver configured to sample the input signal to produce a plurality of input samples, a reference sequence generator configured to generate a reference signal, and a correlator configured to correlate the first and second signals with the reference signal to detect a correlation event, the correlator including a first buffer configured to receive signals from the first input and a second buffer configured to receive signals from the second input, wherein the correlator is configured to process the first signal in the first buffer, while the second buffer receives the second signal.

Preamble detection in wireless systems with intermittent reception

An acquisition detector and method include a preamble detector configured to search in a plurality of symbols for a preamble match with a known preamble pattern when a power level of the input signal exceeds a determined noise threshold. The acquisition detector further includes a frame delimiter detector configured to search in the plurality of symbols for a frame delimiter match with a known frame delimiter pattern when the preamble match is identified and the power level of the input signal exceeds a determined noise threshold.

Acquisition of a data packet having a short preamble

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Austin, TX, United States of America

Khurram Waheed