Abstract: To maximize throughput, an optimization method includes determining at least one precoding matrix and at least one combining matrix together according to Bayesian Optimization, Causal Bayesian Optimization, or Dynamic Causal Bayesian Optimization, and outputting the at least one precoding matrix and the at least one combining matrix. The at least one precoding matrix is configured for at least one precoder of a transmitter. The at least one combining matrix is configured for at least one combiner of at least one receiver.

Abstract: According to an aspect of the present invention, there is provided a ultra-wideband (UWB) system comprising: a memory in which a UWB ranging factor definition program is embedded; and a processor which executes the program, wherein the processor predefines UWB ranging factors to define a scrambled timestamp sequence (STS) index in consideration of a characteristic of an n-byte random value that is changed every ranging.

Abstract: Devices, systems, methods, and non-transitory media facilitate image rejection for a radio frequency signal with a wideband carrier. Wideband signals from a device may be analyzed, the wideband signals corresponding to a wideband channel. Each wideband signal may correspond to a sinusoidal electrical signal with IQ amplitude and phase modulation. An in-phase component (I) of a wideband signal may be determined. A quadrature component (Q) of the wideband signal may be determined. Based on the determined I and Q, a wideband IQ imbalance may be determined. A scalar error based on the wideband IQ imbalance may be obtained. The scalar error may be mapped to a vector error plane. Orthogonal error vector points that are based on the mapping may be determined. The wideband IQ imbalance of the device may be compensated based on adjusting an IQ setting of the device with the orthogonal error vector points.

Abstract: The present invention is proposed to solve the above problems and is directed to providing a UWB system comprising: a memory in which a UWB ranging factor definition program is embedded; and a processor which executes the program, wherein the processor predefines UWB ranging factors to define an encryption key in consideration of a unique m-byte key characteristic for each set of a vehicle and a device.

Abstract: The ultra-wideband (UWB) system includes an input unit configured to receive information on a separation distance between a tag and a vehicle, a memory in which a ranging program corresponding to the separation distance is embedded and a processor which executes the program, wherein the program determines a ranging scheme and an anchor to perform ranging according to the separation distance.

Abstract: Provided are M signal processors that respectively generate modulated signals for M reception apparatuses (where M is an integer equal to 2 or greater), a multiplexing signal processor, and N antenna sections (where N is an integer equal to 1 or greater). When transmitting multiple streams, each of the M signal processors generates two mapped signals, generates first and second precoded signals by precoding the two mapped signals, periodically changes the phase of signal points in the IQ plane with respect to the second precoded signal, outputs the phase-changed signal, and outputs the first precoded signal and the phase-changed second precoded signal as two modulated signals. When transmitting a single stream, each of the M signal processor outputs a single modulated signal. The multiplexing signal processor multiplexes the modulated signals output from the M signal processors, and generates N multiplexed signals. The N antenna sections respectively transmit the N multiplexed signals.

Abstract: A constant amplitude Radio Frequency (RF) signal is created by ordering complex information bearing symbols in the frequency domain along with their complex conjugates, and performing an inverse Fourier transform. This produces an analytic real-only transformed baseband signal. The real-only baseband signal is used to linearly vary the phase angle of a carrier wave while its amplitude remains constant. After reception, multi-path distortion is canceled. A time series of recovered phase angle is un-transformed with a FFT (fast Fourier transform) to produce I (in-phase) and Q (quadrature) samples. Demodulation occurs in a receiver by recovering carrier's phase angle vs. time. Forward error correction may be applied to data if desired. This may be called PM-OFDM (Phase Modulated-orthogonal frequency division multiplexing).

Abstract: By a transmission method according to one aspect of the present disclosure, in a broadcasting system that generates a first broadcasting signal and a second broadcasting signal by performing multi-antenna encoding on program data, and wirelessly transmits a first broadcasting signal and a second broadcasting signal, a first transmit station transmits the first broadcasting signal, a second transmit station transmits the second broadcasting signal, the first transmit station and the second transmit station transmit the first broadcasting signal and the second broadcasting signal to an overlapping area at an identical time using an overlapping frequency band, polarized wave transmitted from the first transmit station differs from polarized wave transmitted from the second transmit station, and arrangement of the first transmit station differs from arrangement of the second transmit station.

Abstract: Systems and methods for wideband RF interference detection and suppression include an open-circuit stub, a first voltage peak detector, a second voltage peak detector, an analog-to-digital converter (ADC), and a controller. The open-circuit stub is configured to receive an input signal. The first voltage peak detector is coupled at the open end of the open-circuit stub and configured to output a first voltage signal based on a portion of the input signal. The second voltage peak detector is coupled a distance away from the open end of the open-circuit stub and configured to output a second voltage signal based on the portion of the input signal. The controller is configured to generate an output control signal operable to adjust a signal filter based on the first digital voltage signal and the second digital voltage signal to suppress the portion of the input signal.

Abstract: A data transmission circuit may include a plurality of data transmission lines configured to transmit a victim data signal through a victim data transmission line, and transmit an adjacent data signal through an adjacent data transmission line disposed adjacent to the victim data transmission line; and a data input/output circuit configured to control a reference voltage level reflected into the victim data signal on the basis of data pattern information of the adjacent data signal, and compare the victim data signal to the reference voltage level and output the comparison result.

Abstract: A method for designing a low-complexity linear minimum mean squared error (LMMSE) and zero-forcing (ZF) receivers for MIMO-RCP-OTFS system is disclosed. The method includes steps of: computing a received signal vector (r) and structure of a matrix (?) using a channel matrix (H); reordering the matrix (?) to reduce bandwidth of the matrix (?); computing inverse of a banded matrix (G=LU) by multiplying the matrix (?) with permutation matrix (P) and with transpose of permutation matrix (PT) using Cholskey decomposition; calculating LMSSE/ZF equalized vector ({tilde over (r)}ce) by multiplying inverse of banded matrices with Bw bandwidth (L and U), with the received signal vector (r=Pr) using forward and backward substitution algorithms; reordering the vector ({tilde over (r)}ce) to calculate vector (y); and calculating data vector ({circumflex over (d)}) representing an estimation of low-complexity LMMSE/ZF equalization by multiplying Hermitian matrix (B) with the vector (y).

Abstract: Systems and methods of reducing SNR and increasing bandwidth of received signals are disclosed. LNAs receive signals from an antenna via a common input matching network. The amplified signals are downconverted, filtered and digitized before being coherently combined at a DSP. Depending on the LO frequencies used by mixers in the different receiver paths, the combined signals reduce the SNR when the LO frequencies are the same by reducing the non-correlated noise introduced by the LNAs or increase the bandwidth processed when the LO frequencies are different. The bandwidths are contiguous or non-contiguous.

Abstract: A method for providing a self-reliant secondary network of communication nodes using resources associated with a primary network defining sector beams using corresponding resources including respective SSBs includes performing a beam search with respect to the sector beams, performing beam detection to detect neighboring beams among the sector beams, and performing geospatial beam selection to define a selected set of SSBs of respective ones of the sector beams as being geospatial white space unlikely to interfere with the primary network when utilized by the communication nodes in the secondary network. The method may further include performing power control with respect to the selected set of SSBs, and applying medium access control protocols to enable the secondary network to use the selected set of SSBs of the primary network.

Abstract: A high-frequency circuit includes a power amplifier for a communication band A, and a power amplifier for a communication band B. Transmission in the communication band A, transmission in the communication band B, and reception in the communication band C can be simultaneously used. A frequency range of intermodulation distortion generated between a second harmonic wave of a transmission signal of the communication band A and a fundamental wave of a transmission signal of the communication band B, overlaps with at least part of a reception band of the communication band C. The power amplifier includes amplifying elements and an output trans including coils. One end of the coil is connected with an output of the amplifying element, the other end of the coil is connected with an output of the amplifying element, and one end of the coil is connected with an output terminal of the power amplifier.

Abstract: Systems and methods for low-power auto-correlation antenna selection for multi-antenna systems are disclosed. In particular, a computing device, such as an Internet of Things (IoT) computing device, may include a transceiver operating with multiple antennas. For example, the computing device may operate under a low-power wireless standard such as Long Range BLUETOOTH LOW ENERGY (LR BLE). In an exemplary aspect, an antenna from amongst the multiple antennas may be selected based on which antenna is receiving a best copy of a periodic signal. The periodic signal is likely indicative of a preamble pattern and, as such, may be used to activate a cross-correlation circuit for signal detection confirmation. Power consumption is reduced by delaying activation of the cross-correlation circuit until a likely signal is detected by detection of the periodic signal.

Abstract: Systems and methods are described for connecting with LEO satellites while reducing emissions toward GEO satellite communications. A system to implement the instant techniques may include a system comprised of a user communications equipment and a LEO constellation. The user equipment (“UE”) may comprise a communications modem and an active antenna unit with a transmit and receive beamformer. In further implementations, the UE may include additional receive only beamformers. The LEO constellation can have a regenerative payload or bent pipe, and can include orbits at different altitudes. Methods as described herein may include a procedure by which the user equipment and LEO satellite work together to identify candidate serving satellites, and select the one that allows to meet the power density requirements to avoid interfering with the GEO satellites.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a first wireless communication device may transmit, to a second wireless communication device, a time and/or frequency synchronization message using a first radio frequency (RF) technology, wherein the time and/or frequency synchronization message is used to obtain synchronization information for a second RF technology. The first wireless communication device may transmit, to the second wireless communication device, a first set of ranging measurement signals associated with the second RF technology. The first wireless communication device may receive, from the second wireless communication device, a second set of ranging measurement signals associated with the second RF technology. Numerous other aspects are described.

Abstract: An antenna system having an antenna array including at least first and second phased array antennas, and a method for field-calibrating the antenna array. Before and after a handover period, communication with respective first and second external satellites or other communication systems is performed using both the first and second antennas. A first beam is formed prior to the handover period. During a first portion of the handover period: a second beam is formed for the communication with the first satellite using the first antenna; the second antenna is deactivated for external communication; and the second antenna is calibrated. During a second portion of the handover period, the second antenna is reactivated for a handed over communication with the second satellite by forming a third beam using the second antenna, while the first antenna maintains its communication with the first satellite via the second beam.

Abstract: Methods, systems, and devices for wireless communications are described that provide for receive chain selection at a user equipment (UE) with efficient switching between a reduced number of receive chains and an increased number of receive chains for downlink communications based on conditions at the UE. A UE may adaptively adjust the number of active receive chains based on downlink grant activity, channel conditions, network parameters, or any combinations thereof. An estimator block at the UE may determine to adjust the number of receive chains based on a number of downlink grants within one or more time periods. In some cases, grants for an amount of data that exceeds a threshold may be qualified in order to be counted at the estimation block. Further, a transient state may be provided where the UE may maintain a higher number of active receive chains until UE feedback is provided.

Abstract: A radio frequency module includes: a module substrate having a main surface; a conductive member to partition the main surface into regions in a plan view of the main surface, and being set to ground electric potential; a switch disposed in one of the regions and connected to an antenna connection terminal; a power amplifier disposed in one of the regions and connected to the antenna connection terminal via the switch; and a low-noise amplifier disposed in one of the regions and connected to the antenna connection terminal via the switch.