Patent classifications
H04L27/367
RF SYSTEM USING PR-ASK WITH ORTHOGONAL OFFSET
An RF system using PR-ASK with orthogonal offset is disclosed. In some embodiments, the system includes a PR-ASK signal generator and an orthogonal offset generator. The PR-ASK signal generator can produce a signal representing a sequence of symbols, for example, RFID symbols. The orthogonal offset generator can shift the PR-ASK signal trajectory away from the origin while maintaining the time domain requirements for an RFID signal, such as waveform edge rise and fall times. In some embodiments stored waveforms incorporating the controlled orthogonal offset are used to synthesize a sequence of symbols. The stored waveforms may also include nonlinear and/or linear predistortion to reduce computational complexity. The waveforms can be represented in Cartesian coordinates for use in a direct conversion transmitter or polar coordinates for use in a polar modulation transmitter. An RFID system can also include a receiver to receive incoming RFID signals.
RECURSIVE LINEARIZATION OF A NON-LINEAR MODEL FOR AN ELECTRONIC DEVICE
There is provided mechanisms for enabling linearization of a non-linear electronic device. A method is performed by a linearizer device. The method comprises receiving an input signal destined to be input to the non-linear electronic device. Input-output characteristics of the non-linear electronic device is represented by a model. The model is defined by a mathematical expression, and wherein input-output characteristics of the linearizer device is given by the linearization function. The linearization function is determined by applying a function recursion to the mathematical expression of the model. The method comprises obtaining an output signal by subjecting the input signal to the linearization function. The method comprises providing the output signal, instead of the input signal, as input to the non-linear electronic device, thereby enabling linearization of the non-linear electronic device.
NON-LINEARITY ESTIMATION FOR ENVELOPE TRACKING PA
A base station may identify one or more signaling messages or pilots usable for identifying a combined PA and ET non-linearity model associated with the base station. The combined PA and ET non-linearity model may be associated with a PA circuitry and an ET circuitry. The PA circuitry and the ET circuitry may be associated with the base station. The base station may transmit, to the UE, and the UE may receive, from the base station, the one or more signaling messages or pilots. The UE may identify a combined PA and ET non-linearity model associated with the base station based on the one or more signaling messages or pilots. The UE may compensate for a distortion in one or more subsequent signals from the base station based on the identified combined PA and ET non-linearity model.
ENHANCED DPD METHOD TO CORRECT GAIN FLATNESS FOR WIRELESS COMMUNICATIONS SYSTEMS
In a dynamic signal traffic scenario, a narrowband to wideband transition in a DPD system results in a tilt in the output spectrum until the next DPD adaptation cycle occurs. To address this problem, regularization term is applied with a weighing factor when performing DPD coefficient estimation and adaptation. The regularization term can be obtained from in a variety of ways: using pre-stored waveforms, through factory or in-situ calibration, or through an adaptive or opportunistic update by observing the system. Application of the regularization term improves the spectrum flatness for a narrow to wideband signal transition, and does not require transmitting additional calibration tones to correct the gain flatness.
DIGITAL PREDISTORTION WITH HYBRID BASIS-FUNCTION-BASED ACTUATOR AND NEURAL NETWORK
Systems, devices, and methods related to hybrid basis function, neural network-based digital predistortion (DPD) are provided. An example apparatus for a radio frequency (RF) transceiver includes a digital predistortion (DPD) actuator to receive an input signal associated with a nonlinear component of the RF transceiver and output a predistorted signal. The DPD actuator includes a basis-function-based actuator to perform a first DPD operation using a set of basis functions associated with a first nonlinear characteristic of the nonlinear component. The DPD actuator further includes a neural network-based actuator to perform a second DPD operation using a first neural network associated with a second nonlinear characteristic of the nonlinear component. The predistorted signal is based on a first output signal of the basis-function-based actuator and a second output signal of the neural network-based actuator.
TRAFFIC MANAGEMENT TECHNIQUE FOR VARIABLE BANDWIDTH NETWORKS USING RSVP
An example system comprises a router configured to receive a bandwidth update associated with a change in bandwidth over a wireless channel, determine if the change in bandwidth identified in the bandwidth update results in bandwidth being over-reserved at at least one priority level, previously reserved bandwidth of the wireless channel being associated with a plurality of different priority levels, the previously reserved bandwidth being previously reserved based on a plurality of path requests from a head end router, each path request including at least one priority level and a bandwidth reservation request, if the change in bandwidth results in bandwidth being over-reserved, then preempt a lowest priority path request, based in the preemption of the lowest priority path request, update reserved bandwidth of the wireless channel of at least one priority level, and provide a message to the head end router regarding the change of bandwidth.
Digital pre-distortion compensation using combined direct and indirect learning
A wireless communications system includes a pre-distortion actuator configured to receive a carrier-modulated signal and convert the carrier-modulated signal into an output signal. The system includes one or more antennas configured to receive the output signal and transmit the output signal, one or more power amplifiers electrically coupled between the pre-distortion actuator and the one or more antennas and a receiver configured to receive the output signal over-the-air and generate feedback based on the output signal. The pre-distortion actuator is configured to generate the output signal by applying a correction to the carrier-modulated signal that cancels out nonlinearities associated with the one or more antennas and/or the one or more power amplifiers. The pre-distortion actuator is configured based on the feedback.
DPD TRAINING AND CALIBRATION
Methods, apparatuses, and computer-readable medium for DPD are provided. An example method may include receiving, from a base station, an uplink grant associated with one or more resources. The example method may further include transmitting, to the UE via the one or more resources, a DPD training signal at a first port of a plurality of ports. The example method may further include receiving, at a second port of the plurality of ports, the DPD training signal.
Reduction of peak to average power ratio
A method for Peak to Average Power Ratio (PAPR) reduction at an input of analog to digital converter (ADC) of the receiver, the method includes mapping, by a mapper, an input symbol to an output symbol that maintains a peak power constraint at the input of the ADC; wherein the mapping is responsive to (a) previously transmitted symbols and (b) a state of the channel following a transmission of the current output symbol; transmitting the output symbol by the transmitter; receiving, by the receiver, a received symbol that represents the output symbol; and de-mapping the received symbol, by a de-mapper of the receiver, to a de-mapped symbol that represents the input symbol.
Method for gateway signaling for MISO operation and apparatus therefor
Disclosed herein are a gateway-signaling method for Multiple-Input Single-Output (MISO) operation and an apparatus for the same. An apparatus for transmitting a broadcast signal according to an embodiment of the present invention includes a predistortion unit for performing predistortion for decorrelating signals corresponding to transmitters using the number of transmitters used for MISO and a transmitter coefficient index that are identified using a timing and management packet transmitted through a Studio-to-Transmitter Link (STL), thereby generating a pre-distorted signal; and an RF signal generation unit for generating an RF transmission signal using the pre-distorted signal corresponding to the transmitter coefficient index.