Abstract: A memory interface may include a transmitter that generates multi-level signals made up of symbols that convey multiple bits of data. The transmitter may include a first data path for a first bit (e.g., a least significant bit (LSB)) in a symbol and a second data path for a second bit (e.g., the most significant bit (MSB)) in the symbol. Each path may include a de-emphasis or pre-emphasis buffer circuit that inverts and delays signals received at the de-emphasis or pre-emphasis buffer circuit. The delayed and inverted data signals may control de-emphasis or pre-emphasis drivers that are configured to apply de-emphasis or pre-emphasis to a multi-level signal.

Abstract: Phased array antenna systems and methods for operating phased array antenna systems to efficiently generate multiple beams from a single phased array aperture are disclosed. Elements included in a phased array antenna are randomly assigned to generate one of first or second beams. A phase index for the first set of elements is iterated n times, and a total difference in phase amounts for neighboring elements belonging to different ones of the first and second sets is calculated for each of the n iterations. The phase index resulting in the smallest calculated difference is applied to generate the first beam. The first and second beams are generated from the single phased array aperture simultaneously.

Abstract: Systems and methods for iterative distributed beam selection include a device including at least one of a first head wearable display (HWD), a second HWD, a first console or a second console. The device detects a predefined condition. The device performs a first distributed beam selection responsive to detecting the predefined condition. Performing the first distributed beam selection includes performing beamforming to provide a first plurality of beams for a first link between the first HWD and the first console, selecting a first beam of the first link with a highest signal-to-interference-plus-noise ratio (SINR) from the first plurality of beams, performing beamforming to provide a second plurality of beams for a second link between the second HWD and the second console while the first beam of the first link is active, and selecting a second beam of the second link with a highest SINR from the second plurality of beams.

Abstract: This application provides a beam training method and apparatus. The method includes: A first access point AP determines first information. The first information is used to indicate an association beamforming training A-BFT time period, the A-BFT time period is used to perform A-BFT between a plurality of APs and a station STA within coverage of the plurality of APs, and the plurality of APs include the first AP and at least one second AP. The first AP sends the first information. A first STA receives the first information, and determines, based on the first information, a time period for performing sector sweep. The beam training method and apparatus in embodiments of this application can be used to control the plurality of APs and a plurality of STAs to perform association beamforming training.

Abstract: Methods, systems, and devices for wireless communications are described. A user equipment (UE) may transmit a random access preamble to a base station as part of a two-step random access procedure. The UE may generate the preamble by identifying a discrete Fourier transform (DFT) matrix and generating a set of sequences based on the DFT matrix. Each sequence of the set of sequences may be generated by selecting a column of the DFT matrix and performing deterministic sampling of respective entries from the selected column in accordance with a sampling function. The UE may then select a sequence from the set of sequences based on generating the set of sequence. The UE may transmit the selected sequence to a wireless device (e.g., a base station).

Abstract: A method is disclosed for a transmitter apparatus configured to transmit signals to a receiver apparatus using a beam selected from a plurality of available beams, wherein a set of the plurality of available beams is for beam selection measurements by the receiver apparatus. The method comprises determining a collection of linear combinations of beams of the set, wherein the cardinality of the collection is lower than a cardinality of the set, and transmitting each of the linear combinations of beams for beam selection measurements by the receiver apparatus. A method is also disclosed for a receiver apparatus configured to receive signals from a transmitter apparatus via a beam selected from a plurality of available beams.

Abstract: The present disclosure provides a beam failure recovery method and a UE. The beam failure recovery method includes: performing beam failure recovery using non-contention-based random access; and performing the beam failure recovery using contention-based random access in the case that the non-contention-based random access fails.

Abstract: Various embodiments disclosed herein provide for a low complexity transmitter structure for active antenna arrays by reducing the number of digital predistortion extraction loops that need to be performed. Digital predistortion (DPD) corrects any non-linearities in a power amplifier. By determining which power amplifiers have similar characteristics in an array, and thus may use similar predistortion coefficients, once the DPD coefficients are determine for one of the grouped power amplifiers, DPD can be performed on each of the grouped power amplifiers based on the DPD coefficients.

Abstract: A wireless communication device transmits beam sweeping information that indicates a beam sweeping property of the device, and a network node in an associated wireless communication network configures transmission or reception beamforming with respect to the device at one or more Transmission/Reception in the network, based on the beamforming property. Among the various advantages flowing from configuring network-side beamforming for the device in view of the beamforming property, the network need not configure its beamforming operations according to worst-case or minimum-capability assumptions for the device, and, instead tailors its transmission or reception beamforming in dependence on the beamforming property of the device.

Abstract: Embodiments of the present disclosure provide a method, apparatus and computer program products for DC offset degradation. A method implemented in a massive multi-input multi-output (MIMO) system, which comprises a plurality of receiver branches, includes receiving a radio frequency (RF) signal in the plurality of receive branches. The method further includes configuring different local frequencies of a plurality of local oscillators respectively in the plurality of receiver branches according to a carrier frequency of the RF signal, to enable direct current (DC) offsets in the plurality of receiver branches to be distinguishable from each other in frequency.

Abstract: A radio frequency (RF) control circuit is provided. The RF control circuit includes power amplifier (PA) circuitry for amplifying an RF signal and control circuitry configured to improve linearity of the PA circuitry based on a PA signature(s) already available and utilized to perform digital pre-distortion (DPD) in the RF control circuit. In examples discussed herein, the control circuitry determines a performance deviation of the PA circuitry based on the PA signature and continuously adjusts a bias voltage(s) supplied to the PA circuitry until the performance deviation is reduced to a predetermined performance deviation threshold. By continuously monitoring the performance deviation based on the PA signature(s) and adjusting the bias voltage(s), the control circuitry can detect and correct an operation abnormality of the PA circuitry in a timely manner. As a result, it is possible to maintain linearity in the PA circuitry for enhanced PA performance.

Abstract: An apparatus, method and computer readable medium for special thermal density reduction by antenna thinning. A system comprises N transmit/receive (TX/RX) chains, where each TX/RX chain comprises an RFFE and each RFFE comprises one or more thermal sensors configured to measure heat in the RFFE. An antenna array coupled to the plurality of TX/RX chains. A codebook that comprises a plurality of code words configured to respond to real-time heat measurements from the thermal sensors in each TX/RX chain is configured to switch off selected TX/RX chains to reduce thermal density at the antenna array while maintaining M RFFEs switched on, where M<N and the desired beamforming gain is 10 log 10(M).

Abstract: A method and system/circuit for multi-beamforming signal processing are provided. The circuit includes a plurality of basic modules associated with a plurality of transducers. Each basic module includes a first and second processing stages operative for introducing time delays of higher and lower temporal resolutions to the signals processed thereby respectively, and a path selector multiplexer module managing the signal coupling between the first and second stages. The first processing stage is connectable to one of the transducers via a first port and includes a network of first type time delay channels defining L signal paths operative at a relatively high sampling rate and adapted for providing L respectively different time delays of high temporal resolution. The second processing stage includes an array of N second type time delay channels operable for shifting signals processed thereby by any number up-to K samples of a lower sampling rate.

Abstract: This transmitter is provided with: a digital delay circuit which delays a 1-bit digital RF signal on the basis of another 1-bit digital RF signal; an amplifier which amplifies a signal output by the digital delay circuit; and a band-pass filter which allows signals in a prescribed frequency band, from among signals output by the amplifier, to pass. A signal output by the band-pass filter is input into a corresponding one antenna element from among a plurality of antenna elements, and controls the directionality of a beam formed by the plurality of antenna elements.

Abstract: This application provides a beam training method and apparatus. The method includes: generating and sending a set up frame, where the set up frame includes M pieces of time information, each piece of time information corresponds to one receiving device in the M receiving devices, each piece of time information is used to indicate a feedback information sending moment of the corresponding receiving device, each piece of time information is further used to indicate an acknowledgment information receiving moment of the corresponding receiving device; receiving a sector sweep SSW frame, generating feedback information based on the SSW frame; sending the feedback information at a feedback information sending moment indicated by corresponding time information; receiving, at an acknowledgment information receiving moment indicated by the corresponding time information, acknowledgment information. Therefore, a training time can be shortened and signaling overheads can be reduced.

Abstract: A receiver device implements enhanced data reception with edge-based clock and data recovery such as with a flash analog-to-digital converter architecture. In an example embodiment, the device implements a first phase adjustment control loop, with for example, a bang-bang phase detector, that detects data transitions for adjusting sampling at an optimal edge time with an edge sampler by adjusting a phase of an edge clock of the sampler. This loop may further adjust sampling in received data intervals for optimal data reception by adjusting the phase of a data clock of a data sampler such a flash ADC. The device may also implement a second phase adjustment control loop with, for example, a baud-rate phase detector, that detects data intervals for further adjusting sampling at an optimal data time with the data sampler.

Abstract: A method includes, at a first node: transmitting a first synchronization signal at a first time according to a first clock of the first node; back-coupling the first synchronization signal to generate a first self-receive signal; calculating a time-of-arrival of the first self-receive signal according to the first clock; and calculating a time-of-arrival of the second synchronization signal according to the first clock. The method also includes, at the second node: transmitting the second synchronization signal at a second time according to a second clock of the second node; back-coupling the second synchronization signal to generate a second self-receive signal; calculating a time-of-arrival of the second self-receive signal according to the second clock; and calculating a time-of-arrival of the first synchronization signal according to the second clock. The method S100 further includes calculating a time bias and a propagation delay between the pair of nodes based on the time-of-arrivals.

Abstract: Methods and apparatus for facilitating the use of a plurality of antenna beams for communications purposes are described. In at least some embodiments beam priority information is periodically exchanged. Multiple timers are used to ensure beam information is exchanged at intervals intended to facilitate reliable beam synchronization and to control switching to one or more alternative beams in a predictable manner in the event beam change information or beam synchronization information is lost. In some but not all embodiments a wideband beam is used to communicate beam synchronization information when synchronization using narrower beams used for normal data communication is lost.

Abstract: A wireless device switches from a first downlink bandwidth part (BWP) to a second downlink BWP identified with a downlink BWP index. Based on the second downlink BWP being configured with beam failure recovery (BFR), a first uplink BWP is switched to a second uplink BWP identified with a uplink BWP index that is the same as the downlink BWP index. The second downlink BWP is switched to a third downlink BWP. Based on the third downlink BWP not being configured with BFR, the second uplink BWP is kept as an active uplink BWP.

Abstract: A base station receives, from a wireless device, at least one first measurement report of at least one synchronization signal of a cell. One or more channel state information reference signals (CSI-RSs) of the cell are selected based on: the at least one first measurement report; and a first antenna port of the one or more CSI-RSs being quasi-collocated with a second port of the at least one synchronization signal. At least one second measurement report of the one or more CSI-RSs is received. At least one first CSI-RS of the one or more CSI-RSs is selected based on the at least one second measurement report. A downlink control information initiating a random access procedure of the cell is transmitted. The random access procedure is based on the at least one first CSI-RS.