Abstract: Multi-drop communications channels can have significantly deep notches in their frequency response causing a corresponding limitation of the effective data transmission rate. A special time-ordered coding method is described which results in the emitted spectrum of the data stream transmitted into the channel having a notch at the same frequency as the notch in the channel frequency response, permitting channel receivers to successfully decode the transmitted data stream. The described coding method may be applied at various multiples of the channel notch frequency to support different throughput rates, and may be combined with other coding techniques such as group or vector signaling codes.

Abstract: The present invention relates to the field of communications technologies, and discloses a method, an apparatus, and a system for suppressing interference in a massive multiple-input multiple-output system, which overcome a disadvantage of sensitivity to a backhaul delay during an inter-cell interference cancellation process in an existing massive multiple-input multiple-output system. A specific embodiment of the present invention includes: obtaining channel correlation matrixes of all links, and further calculating a combined outer precoder set according to the channel correlation matrixes, where each combined outer precoder includes at least one outer precoder, and the outer precoder is a semi-unitary matrix and is not sensitive to a backhaul delay. Technical solutions of the present invention are mainly applied to a process of processing interference in a massive multiple-input multiple-output system.

Abstract: Apparatuses (and methods of manufacturing same), systems, and methods for channel interpolation/estimation and/or frequency tracking suitable for a receiver in a high speed single frequency network (HS-SFN) scenario are described. In one aspect, an estimated frequency offset (FO) correction is calculated for a received signal using at least an FO estimation provided by an automatic frequency control (AFC) in a first feedback loop and a channel estimate is calculated using at least the estimated FO and one or more channel parameter estimates from the AFC in a second feedback loop. In another aspect, a phase locked loop (PLL) receives an lth orthogonal frequency division multiplexing (OFDM) symbol and produces a per-tap phase value for each tap i of the lth OFDM symbol. The per-tap phase values of the lth OFDM symbol are used to generate the PLL output, which is also used as input to a feedback loop.

Abstract: In some example implementations, there may be provided methods for beamforming calibration of active electronically steered arrays (AESA). In some implementations, one or more adders may generate a phase offset by adding phase calibration data from non-volatile memory and phase command data from static memory, and/or generate a gain offset by adding gain calibration data from the non-volatile memory and gain command data from the static memory. Further, a phase-shift circuit can modify, based on the phase offset, a phase of a first output signal, and an amplitude gain circuit can modify, based on the gain offset, an amplitude of the first output signal. In accordance with these implementations, the modified phase of the first output signal and the modified amplitude of the first output signal are provided to enable pre-calibration of the first output signal and/or a first antenna. Related systems, methods, and articles of manufacture are also described.

Abstract: An adaptive analog parallel combiner circuit for receiver data recovery from a communication signal is provided. The circuit includes a summer that sums outputs of a plurality of filter taps in parallel, including zeroth and first through Nth filter taps, each filter tap having as input the communication signal or a version thereof, wherein N is a finite integer greater than or equal to two. The zeroth filter tap has an amplifier with gain controlled by a zeroth adaptive gain control coefficient, and each of the first through Nth filter taps having an all pass filter and gain controlled amplification, with gain controlled by a corresponding one of a first through Nth adaptive gain control coefficients and the all pass filter implementing a transfer function having a zero and a pole equaling each other and at a base frequency divided by a corresponding integer from one through N.

Abstract: Briefly, in accordance with one or more embodiments, a base transceiver station having a first set of antennas and a second set of antennas geographically separated from the first set of antennas transmits a reference signal to a first device, and receives feedback from the first device. The feedback represents information that can be used to construct a weight adjustment vector. The base transceiver station selects a precoding vector from a codebook based at least in part on the feedback received from the first device, calculates the weight adjustment vector based at least in part on the feedback, and applies the weight adjustment vector to the selected precoding vector to provide an adjusted precoding vector. The base transceiver station then may transmit data to the first device using the adjusted precoding vector.

Abstract: A frequency synthesizer with microcode control that allows one or more programmable circuits of a frequency synthesizer system to be programmed using a plurality of microcode instructions. A method includes, setting a frequency synthesizer system to operate in a microcode mode, programming the frequency synthesizer system for microcode execution of a plurality of microcode instructions and executing the plurality of microcode instructions at the frequency synthesizer system to control one or more behaviors of one or more programmable circuits of the frequency synthesizer system.

Abstract: Disclosed herein are system and method embodiments for selection of transmission parameters for transmit diversity terminals. According to an aspect, a method for controlling wireless receive/transmit unit transmission parameters may include configuring a WRTU to transmit dual stream when a first stream is using a predetermined transport format (TF) or subset of the TF. The method may also include applying the configuration to the WRTU.

Abstract: In the subject system, a receiver includes a feed forward circuit, a phase recovery circuit, and a feedback circuit. The feed forward circuit compensates for near reflections and provides an input to the phase recovery circuit and the feedback circuit. The phase recovery circuit performs phase recovery and provides phase recovery information to the feedback circuit. The feedback circuit adjusts and/or corrects a received symbol based at least in part on the received phase recovery information.

Abstract: Pre-distorted transmitters operable over a wide range of frequencies including a plurality of predetermined frequency bands are provided. The transmitters include a programmable digital up-converter and a programmable digital down-converter, an ADC, a DAC, a power amplifier and at least one analog filter arranged along a transmit signal path and a feedback signal path.

Abstract: The teachings herein present a method and apparatus that implement and use a factorized precoder structure that is advantageous in terms of performance and efficiency. In particular, the teachings presented herein disclose an underlying precoder structure that allows for certain codebook reuse across different transmission scenarios, including for transmission from a single Uniform Linear Array (ULA) of transmit antennas and transmission from cross-polarized subgroups of such antennas. According to this structure, an overall precoder is constructed from a conversion precoder and a tuning precoder. The conversion precoder includes antenna-subgroup precoders of size NT/2, where NT represents the number of overall antenna ports considered. Correspondingly, the tuning precoder controls the offset of beam phases between the antenna-subgroup precoders, allowing the conversion precoder to be used with cross-polarized arrays of NT/2 antenna elements and with co-polarized arrays of NT antenna elements.

Abstract: A wireless communication terminal apparatus wherein CoMP communication can normally be performed without increasing the overhead of an upstream line control channel. In this apparatus, a spreading unit primarily spreads a response signal by use of a ZAC sequence established by a control unit. A spreading unit secondarily spreads the response signal, to which CP has been added, by use of a block-wise spread code sequence established by the control unit. The control unit controls, in accordance with sequence numbers and a hopping pattern established therein, the circular shift amount of the ZAC sequence to be used for the primary spread in the spreading unit and the block-wise spread code sequence to be used for the secondary spread in the spreading unit. The hopping pattern established in the control unit is a hopping pattern common to a plurality of base stations that CoMP-receive the response signal.

Abstract: A wireless local area network (WLAN) transmitter includes a baseband processing module and a plurality of radio frequency (RF) transmitters. The processing module selects one of a plurality of modes of operation based on a mode selection signal. The processing module determines a number of transmit streams based on the mode selection signal. The processing of the data further continues by converting encoded data into streams of symbols in accordance with the number of transmit streams and the mode selection signal. A number of the plurality of RF transmitters are enabled based on the mode selection signal to convert a corresponding one of the streams of symbols into a corresponding RF signal such that a corresponding number of RF signals is produced.

Abstract: The present invention is directed to communication systems. According to embodiments of the present invention, a communication system includes at least two communication lanes and a skew management module. The skew management module generates a control current based on output test patterns of the two communication lanes. The control current is integrated and compared to a reference voltage by a comparator, which generates an analog offset signal. A PLL of one of the communication lanes generates a corrected clock signal that is adjusted using the analog offset signal to remove or adjust the skew between the communication lanes. The corrected clock signal is used for output data. There are other embodiments as well.

Abstract: Embodiments include systems and methods for applying a controllable early/late offset to an at-rate clock data recovery (CDR) system. Some embodiments operate in context of a CDR circuit of a serializer/deserializer (SERDES). For example, slope asymmetry around the first precursor of the channel pulse response for the SERDES can tend to skew at-rate CDR determinations of whether to advance or retard clocking. Accordingly, embodiments use asymmetric voting thresholds for generating each of the advance and retard signals in an attempt to de-skew the voting results and effectively tune the CDR to a position either earlier or later than the first precursor zero crossing (i.e., h(?1)=0) position. This can improve link margin and data recovery, particularly for long data channels and/or at higher data rates.

Abstract: An OFDM system uses a normal mode which has a symbol length T, a guard time TG and a set of N sub-carriers, which are orthogonal over the time T, and one or more fallback modes which have symbol lengths KT and guard times KTG where K is an integer greater than unity. The same set of N sub-carriers is used for the fallback modes as for the normal mode. Since the same set of sub-carriers is used, the overall bandwidth is substantially constant, so alias filtering does not need to be adaptive. The Fourier transform operations are the same as for the normal mode. Thus fallback modes are provided with little hardware cost. In the fallback modes the increased guard time provides better delay spread tolerance and the increased symbol length provides improved signal to noise performance, and thus increased range, at the cost of reduced data rate.

Abstract: The present disclosure relates to a communication method and system for converging a 5th-Generation (5G) communication system for supporting higher data rates beyond a 4th-Generation (4G) system with a technology for Internet of Things (IoT). The present disclosure may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety services. Provided are a method and user equipment for sending feedback information to a base station.

Abstract: A system and method are described for calibrating a clock used in data transmission. In one example, dynamic phase adjustment circuitry can be used for any of a variety of different protocols to shift the clock phase with respect to a data signal. In the most typical example, the clock phase is shifted 90 degrees relative to a transmission data signal. The dynamic phase adjustment circuitry can use two cascaded programmable delay lines coupled in series. Each programmable delay line represents a half phase delay of 90 degrees. A controller can monitor an output of the programmable delay lines and incrementally add or subtract programmable delay line elements until a 180 degree phase is detected relative to a data transmission. An output clock can then be used by applying the result of the calibration delay element to the clock under discussion.

Abstract: Disclosed herein are a terminal and an operation method thereof in a MIMO system. The terminal may use a reference signal for channel state measurement from a base station to calculate a first value that is a ratio of a signal transmitted from the base station to noise and a second value that is a ratio of interference from the base station and the noise. Further, the terminal may generate bit information by comparing a ratio of the second value and the first value with a predetermined threshold value and feedback the first value and the bit information to the base station.

Abstract: Circuits, devices, methods for decision feedback equalization are described. A decision feedback circuit can include L N-tap decision feedback equalizer (DFE) branch input lines and an unfolding multiplexer array network. The network is configured to generate at least one unfolded output based on inputs from a subset of the branch input lines and includes a plurality of multiplexer arrays wherein outputs from a first multiplexer array in the plurality of multiplexer arrays are connected to selection lines of a second multiplexer array in the plurality of multiplexer arrays.