Silicon Laboratories Inc.

St-ericsson Sa

Nxp B.v.

Guner Arslan

Yan Zhou

Shaojie Chen

Robert Mark Gorday

Wentao Li

Jake Gordon Wood

Charles Anthony Weinberger

He Gou

David S Trager

Vitor Pereira

David Anderton

Jeffrey A Tindle

Pascal Blouin

Marc Leroux

Chester Yu

Trenton John Grale

Bryan K Murawski

Yi Shen Yeh

Xushuai Qu

J A Bolton

John B Youngblood

Amey Naik

Casey Ryan Weltzin

Logan A Lucas

Mehmood Ur Rehman Awan

A wireless communications device includes a receiver having a phase detector configured to extract frequency offset and provide a corresponding error signal generated based on a baseband version of a received radio frequency signal and an expected transmitted data signal. The receiver has a phase-locked loop configured to generate an error correction signal based on a phase of the error signal and a predicted instantaneous phase of the error signal. The receiver has a correction circuit configured to provide a corrected baseband version of the received radio frequency signal based on the baseband version of the received radio frequency signal and the error correction signal. The receiver may have a re-encoding-based processing circuit configured to provide the expected transmitted data signal based on a preliminarily decoded symbol.

Kalman filter based phase-locked loop with re-encoding based phase detector

A system and method to improve the accuracy of the measurement of round trip delay in a high accuracy distance measurement (HADM) is disclosed. In one embodiment, the traditional parabolic estimation is used. However, an estimation error is used to compensate for the inaccuracy of the parabolic estimation. This correction may reduce the standard deviation of a measurement by 50% or more. In another embodiment, the parabolic estimation is not used; rather, a different estimation is used, such as an absolute value estimation. In some tests, the absolute value estimation improved the mean measurement value and reduced the standard deviation by 50%.

Improving accuracy of round-trip time (RTT) in high accuracy distance measurements (HADM)

A system that is capable of detecting a Man in the Middle attack is disclosed. The system includes a receive circuit for receiving incoming packets. The system also includes a digitized model of at least part of the receive circuit and optionally part of the transmit circuit. The system compares the output from the digitized model with the output from the read circuit to determine the likelihood of a Man in the Middle Attack. In certain embodiments, the digitized model is a finite impulse response filter with multiple taps. The system correctly identifies Man in the Middle attacks more than 90% of the time when the signal to noise ratio is greater than 20 dB.

Man in the middle attack detection in BLE high accuracy distance measurement

In one embodiment, an apparatus includes: a low noise amplifier (LNA) to receive and amplify a radio frequency (RF) signal, the LNA having a first controllable gain; a mixer to downconvert the RF signal to a second frequency signal; a programmable gain amplifier (PGA) coupled to the mixer to amplify the second frequency signal, the PGA having a second controllable gain; a digitizer to digitize the second frequency signal to a digitized signal; a demodulator coupled to the digitizer to demodulate the digitized signal; an automatic gain control (AGC) circuit to control one or more of the first controllable gain and the second controllable gain; and an AGC settling circuit to cause the demodulator to begin operation in response to determining that the AGC circuit has settled.

Apparatus for determining when an automatic gain control circuit has settled

A system that includes a Viterbi Equalizer having adaptive signal levels is disclosed. Each branch metric of the Viterbi Equalizer compares the value of the incoming bit to one of a plurality of different expected signal levels. A set of default signal values may be used by the Viterbi Equalizer. The system is also configured to determine whether these default expected signal levels are acceptable by monitoring the incoming data bits. If it is determined that the actual signal levels of the incoming data bits differ from the default expected signal levels by more than a predetermined amount, the signal levels used by the Viterbi Equalizer may be changed from default signal levels to the adaptive signal levels. The adaptive signal levels may be determined using the synchronization pattern.

Signal level tracking and application to Viterbi equalization

A wireless device may include: a radio frequency (RF) front end circuit to receive and process an RF signal; a mixer to downconvert the RF signal to a second frequency signal; a digitizer to digitize the second frequency signal; a channel filter to channel filter the digitized signal; a selection circuit having a first input coupled to the channel filter and a plurality of outputs each to couple to one of a plurality of demodulators; and the plurality of demodulators coupled to the selection circuit. The selection circuit may route the channel filtered digitized signal to a first demodulator of the plurality of demodulators based on a first configuration setting. The wireless device may also include a non-volatile storage with a configuration file including the first configuration setting. The configuration file may be automatically generated by a hardware configurator in response to a plurality of user input parameters.

System, apparatus and method for automatically determining configuration parameters for wireless devices

A system and method for detecting the presence of a Bluetooth or Zigbee signal within a short period of time is disclosed. The signal identification circuit has two stages, a first stage that processes windows to determine whether noise is present, and a second stage that processes long windows to determine whether the signal is a particular lower-power network protocol. The signal identification circuit can be configured to detect Bluetooth at 1 Mbps, Bluetooth at 2 Mbps or Zigbee. The signal identification signal may be used to allow a lower-power network controller to coexist with a high duty cycle WiFi controller. The signal identification circuit may also be used for other functions, such as powering on a lower-power network controller, determining CCA, or determining which channel a packet is being transmitted on.

Fast signal identification of Bluetooth, ZigBee and other network protocols

A Viterbi Equalizer having a limited number of stages is disclosed. In some embodiments, the Viterbi Equalizer may have only four stages. The Viterbi Equalizer produces soft decisions, which comprise a final decision and reliability information related to that final decision. The Viterbi Equalizer is able to provide reliability information even if all paths do not converge on the final decision at the last stage. The reliability information is calculated based on if and when the paths in the trellis converge on a final decision. This reliability information can be used downstream, such as by another Viterbi Algorithm block to perform forward error correction. The use of soft decision provides gains of up to several dB in performance. Additionally, the Viterbi Equalizer is low cost and readily implemented in hardware or software.

Viterbi equalizer with soft decisions

A system and method for detecting and receiving packets that are transmitted over a network that utilizes a plurality of channels is disclosed. The system includes a radio circuit, which can be configured to receive packets over a plurality of channels, a processing unit, and a memory in communication with the processing unit. The processing unit loads a set of operating parameters in the radio circuit, which enables the radio circuit to detect and receive packets on a particular channel. If a preamble is not detected within a predetermined time period, the system hops to a different channel by loading a second set of operating parameters in the radio circuit. This process can be repeated for an arbitrary number of channels.

Software emulation of parallelized packet detection across channels

A system and method for detecting and receiving Z-Wave Beams that are transmitted over a plurality of channels is disclosed. The system includes a radio circuit, which includes a Digital Signal Arrival (DSA) circuit and a read channel. The DSA circuit is able to detect the presence of a valid signal on a particular channel, based on received signal power, detected frequency deviation, the magnitude of phase spikes and/or other characteristics. The read channel is able to decode incoming packets. Software is used to control the DSA circuit and the read channel so that, during each wake up period, the FLiRS device monitors all available channels to determine if a Z-Wave Beam is present. If a Z-Wave Beam is detected, the read channel receives the Z-Wave Beam. Otherwise, the FLiRS device returns to sleep mode.

System and method for low power Z-wave beaming detection

A wireless receiver including a front end circuit, an adaptive threshold circuit, and a correlator. The front end circuit converts a wireless signal into a series of digital symbols. The adaptive threshold circuit provides an adaptive correlation threshold that is adapted based on a sync word. The correlator correlates the digital symbols with the sync word using the adaptive correlation threshold. The adaptive correlation threshold may be based on amplitude attenuation of the digital symbols that correspond to transitions of the sync word. The adaptive threshold circuit may be a lookup table that stores different threshold values each corresponding to one of multiple different sync words. Alternatively, the adaptive threshold circuit may be implemented as an evaluation circuit that determines the adaptive correlation threshold based on expected amplitude attenuation of the digital symbols that correspond to transitions of the sync word.

System and method of adaptive correlation threshold for bandlimited signals

In one aspect, a method includes: iteratively, for each of a plurality of code maps each formed based on one of a plurality of base spreading codes: determining, in a computing system, a plurality of metrics for the code map; and computing, in the computing system, a weighted sum for the code map based on at least some of the plurality of metrics. After this iterative operation, a first base spreading code associated with the weighted sum having an optimal value may be selected. This first base spreading code may be used to configure one or more wireless devices with the first base spreading code to cause the one or more wireless devices to communicate coded symbols using the first base spreading code.

Base spreading code determination for a wireless communication protocol

In one aspect, a method includes: receiving, in a configurator for a wireless receiver, a plurality of user-defined parameters for configuring the wireless receiver for wireless communication, the user-defined parameters including pulse shaping information of a pulse shaper of a wireless transmitter to be in communication with the wireless receiver and channel filter information of a channel filter of the wireless receiver; generating a plurality of frequency signals based on a corresponding plurality of predetermined bit sequences and at least two of the plurality of user-defined parameters including the pulse shaping information and the channel filter information; setting a first nominal symbol value based at least in part on an oversampling rate for a demodulator of the wireless receiver; and configuring the wireless receiver with the first nominal symbol value to cause the demodulator of the wireless receiver to operate using the first nominal symbol value.

Growing community of inventors

Austin, TX, United States of America

Guner Arslan