Samsung Electronics Co., Ltd.

Cambridge Silicon Radio Limited

Qualcomm Technologies International, Ltd.

Fei Tong

Jacob Christopher Sharpe

Erik David Lindskog

Andrei Popescu

Hong Wan

Paul Nicholas Fletcher

Myeong-Cheol Shin

Ziming He

Jeongtaek Lee

Mark Gorthorn Rison

Chunyang Yu

Ian K Appleton

Michael John Cowell

Donald G Guy

Paul C McFarthing

Mark Gothorn Rison

A communication device, including a receiver configured to receive a signal comprising a plurality of training symbols and a data symbol; and at least one processor configured to: select, from among the plurality of training symbols, a first training symbol and a second training symbol based on a first parameter and a second parameter; obtain a first symbol difference corresponding to the first training symbol, and a second symbol difference corresponding to the second training symbol; estimate a carrier frequency offset based on the first symbol difference and the second symbol difference; obtain a compensated data symbol corresponding to the data symbol based on the estimated carrier frequency offset; and demodulate and decode the compensated data symbol to obtain decoded data.

Low complexity carrier frequency offset estimation algorithm using known symbols

A one way ranging method estimates a distance between first and second wireless devices using a technique that involves exchanging dual tone RF signals between the devices and, at each of the first and second devices, maintaining 'baseband coherence' between baseband signals carried by the RF signals transmitted and received by each respective device.

Ranging measurement employing baseband coherence

A method for detecting a modification, due to an interferer, of a wireless channel between a transmitting device and a receiving device. First and second samples of channel frequency response (CFR) of the wireless channel are measured within a time interval less than or equal to a pre-established static time interval throughout which the wireless channel is expected to exhibit a static characteristic in an environment without any interferer. An interferer is detected to have modified the wireless channel when a similarity condition reflecting a degree of similarity between the first and second CFR samples is not satisfied.

Detection of spoofing or jamming attacks in wireless communication system

One or more aspects of the techniques and models described herein provide for bidirectional recurrent neural network (BiRNN)-based digital pre-distortion techniques for radio frequency (RF) power amplifiers (PAs). As an example, a digital pre-distorter (DPD) system may implement residual learning and long short-term memory (LSTM) projection layer features to reduce computational complexity and memory requirements. Implementing the described unconventional techniques of applying residual learning in RNN (e.g., in BiLSTM), using LSTM projection to develop a DPD structure, or both, may provide several advantages over preexisting techniques. For instance, the complexity in training and pre-distortion may be reduced and significantly less memory may be required to store the DPD neural network coefficients (e.g., while achieving similar or better linearization performance compared to other LSTM models). Further, faster training convergence speed may be achieved (e.g., compared to other LSTM models).

Residual neural network models for digital pre-distortion of radio frequency power amplifiers

A method of digital memoryless pre-distortion includes receiving an input digital signal from a signal source, calculating a look-up table (LUT) address from the input signal and a power scale, updating an LUT value associated with the LUT address based on the input signal and an output signal that is output from a power amplifier to a wireless communications channel, linearizing the output signal with the updated LUT value, and outputting the output signal to the wireless communications channel. The steps of updating an LUT value associated with the LUT address and linearizing the output signal with the updated LUT value are repeated until a level of linearization is achieved that meets a pre-defined standard.

High performance low complexity memoryless digital pre-distortion

The present disclosure describes systems and methods for time-of-arrival (TOA) estimation techniques. Some embodiments of the disclosure provide for estimating radio propagation path parameters based on a training signal received over a set of active frequencies. The radio propagation path parameters (e.g., fading coefficients for each path) are used to reconstruct a channel frequency response on null frequencies (e.g., frequencies that did not include or carry the received training signal). A time-of-arrival parameter can then be estimated based on the estimated channel frequency response and the reconstructed channel frequency response (e.g., the channel frequency response estimated using both active frequencies and null frequencies).

Channel frequency response reconstruction assisted time-of-arrival estimation method

A measurement method performed at a receiving device involves sequentially receiving RF signals, each comprising a different set of at least first and second tones at differing frequencies. Complex gain responses (CGRs) for each of the first and second tones of each of the RF signals are measured. A phase offset is determined between: i) a phase of the CGR of the second tone of a first RF signal, and ii) a phase of the CGR of the first tone of a second RF signal. A coherent channel frequency (CCF) response of the second tone of the second RF signal is computed by adjusting a phase of the CGR of the second tone of the first RF signal by the phase offset. A processor executes a signal paths calculation algorithm using the CCF response of the second tone of the second RF signal to determine an angle or time of arrival of the first RF signal.

Time / angle of arrival measurement using narrowband signals

An apparatus and method are provided for Doppler estimation of a signal received over a time-varying transmission medium, the method including receiving the signal over a channel of the time-varying transmission medium; sampling a magnitude of the received signal repeatedly over time; identifying unidirectional threshold crossings of the sampled magnitude about a threshold magnitude relative to a mean magnitude; measuring differences between the sampled magnitude and the threshold magnitude for the identified crossings; analyzing the measured differences over time; estimating the time-varying nature of the channel based on the analyzed differences; and transmitting a signal indicative of the estimated time-varying nature.

Low-complexity doppler estimator

A page scanning device configured to generate a sequence mask for an expected frequency hopping sequence, select a first tone among a plurality of detected tones, first determine whether the first tone is included within an expected hop sequence, generate a first tone template in response to determining that the first tone is included within the expected hop sequence, align the first tone template with the plurality of detected tones based on the first tone, second determine whether the first tone template matches the plurality of detected tones, and detect a valid frequency hopping sequence in response to determining that the first tone template matches the plurality of detected tones.

Page scanning devices, computer-readable media, and methods for bluetooth page scanning using a wideband receiver

A wireless communication device configured to select a spatial stream among a plurality of spatial streams, the plurality of spatial streams being included in a received signal vector, the received signal vector being associated with a symbol constellation, calculate a plurality of distance values, each distance value representing a distance between the selected spatial stream and a different hypothesis symbol among a plurality of hypothesis symbols, the plurality of hypothesis symbols corresponding to the symbol constellation, repeat the selection and the calculation for all spatial streams among the plurality of spatial streams not previously selected, and determine a detected symbol of each spatial stream among the plurality of spatial streams based on the plurality of distance values calculated for the plurality of spatial streams.

Apparatuses, computer-readable media, and methods for single dimension maximal likelihood symbol detection

A receiver configured to receive a frequency-modulated transmission having a preamble and a corresponding method are provided, the receiver having a buffer coupled to an input terminal for receiving the transmission, a time-to-frequency transformer coupled to the buffer, an energy aggregator coupled to the transformer, a preamble detector coupled to the aggregator, and a symbol synchronizer coupled to the detector; the method including receiving a sequence of time-domain frequency-modulated samples, transforming the sequence of time-domain samples into a spectrum of frequency-domain data, and matching an actual energy distribution over a plurality of discrete frequencies in the frequency-domain data with an expected energy distribution of the preamble to determine frequency error.

Synchronization for low-energy long-range communications

A method of determining a time of arrival (ToA) of a wireless transmission includes: sampling a signal received in a wireless transmission to generate first data in a time domain, performing a FFT on the first data to generate second data in a frequency domain, dividing the second data by a reference signal to obtain a channel frequency response, performing and IDFT on the channel frequency response to obtain a channel impulse response, determining a peak in the channel impulse response; and determining the ToA based on the peak.

Apparatus, system and method of estimating an arrival time of a wireless transmission

A unified device for adjacent and non-adjacent channels/carriers for processing Physical layer Protocol Data Units (PPDUs) includes a dual-use configuration capable of processing either 80+80 Megahertz (MHz) PPDUs with a single spatial stream (160/80+80 MHz 1&#xd7;1) or 80 MHz PPDUs with two spatial streams (80 MHz 2&#xd7;2).

Unified device for adjacent and non-adjacent channels for processing physical layer protocol data units

Managing access to a time-slotted communications medium by masking interrogatory codes that are contained in signals demarcating time slots of the medium and comparing the masked interrogatory codes against masked response codes. Access to the medium is dependent on the outcome of these comparisons.

Growing community of inventors

Bassingbourn, United Kingdom

Fei Tong