Abstract: An OFDM transmitter and an OFDM receiver respectively transmit and receive N (N?2, N is an integer) control symbols. For each control symbol, a guard interval time-domain signal is, for example, identical to a signal obtained by frequency-shifting at least a portion of a useful symbol time-domain signal by an amount different from any other symbol, or to a signal obtained by frequency-shifting one or both of a portion and a span of a useful symbol interval time-domain signal different from any other symbol by a predetermined amount.

Abstract: A communication apparatus includes a PHY frame generating circuit that generates a PHY frame including either of a short Sector Sweep frame and a Sector Sweep frame; and an array antenna that selects, based on the PHY frame, any sector from among a plurality of sectors and transmits the PHY frame. In a case where, in the PHY frame including the short Sector Sweep frame, a Direction field of the short Sector Sweep frame indicates Initiator Sector Sweep, the PHY frame generating circuit replaces a Short Sector Sweep Feedback field indicating a number of a selected best short Sector Sweep with a Short Scrambled Basic Service Set ID field indicating an abbreviated address generated from an address of a destination communication apparatus.

Abstract: Some embodiments enable improved packet error rate (PER), signal to noise ratio (SNR), channel capacity, aggregated throughput, and communication range in wireless communication systems. For example, an electronic device includes a buffer that stores a first descrambled bit estimate sequence. The electronic device further includes an encoder that receives a descrambling sequence and generates an encoded descrambling sequence and a multiplier circuit that receives a bit estimate sequence and the encoded descrambling sequence and generates a second descrambled bit estimate sequence. The electronic device also includes an adder circuit that combines the first descrambled bit estimate sequence and the second descrambled bit estimate sequence and a decoder that decodes the combined descrambled bit estimate sequence.

Abstract: Systems and methods are disclosed herein for selectively compensating for a specific Intermodulation Distortion (IMO) product(s) of an arbitrary order in a transmitter system. In some embodiments, a method of compensating for one or more specific IMO products in a concurrent multi-band transmitter system comprises generating an IMO correction signal for a specific IMO product as a function of two or more frequency band input signals for two or more frequency bands of a concurrent multi-band signal, the IMO product being an arbitrary order IMD product. The method further comprises frequency translating the IMD correction signal to a desired frequency that corresponds to a Radio Frequency (RF) location of the specific IMO product and, after frequency translating the IMO correction signal to the desired frequency, utilizing the IMO correction signal to compensate for the specific IMO product.

Abstract: A communication system uses multiple communications links, preferably links that use different communications media. The multiple communications links may include a high latency/high bandwidth link using a fiber-optic cable configured to carry large volumes of data but having a high latency. The communications links may also include a low latency/low bandwidth link implemented using skywave propagation of radio waves and configured to carry smaller volumes of triggering data with a lower latency across a substantial portion of the earth's surface. The triggering data may be sent in a data stream as data frames without headers, security information, or error checking codes. The two communications links may be used together to coordinate various activities such as the buying and selling of financial instruments.

Abstract: The present application discloses an information indicating and determining method and apparatus, and a computer storage medium, being used for indicating QCL group information of a DMRS port, enabling a terminal to determine the QCL group information of the DMRS port. The embodiments of the present application provide an information indicating method, comprising: determining QCL group information of a demodulation reference signal DMRS port; and notifying a terminal of the QCL group information.

Abstract: An envelope tracking system includes an instantaneous amplitude circuitry, an instantaneous frequency circuitry, and a two-dimensional (2D) bias voltage selection circuitry. The instantaneous amplitude circuitry is configured to determine an instantaneous amplitude of a transmit signal. The instantaneous frequency circuitry is configured to determine an instantaneous frequency of the transmit signal. The two-dimensional (2D) bias voltage selection circuitry is configured to determine a bias voltage based on both the instantaneous amplitude and the instantaneous frequency of the transmit signal, and control power supply circuitry to supply the determined bias voltage to a power amplifier that is configured to amplify the transmit signal.

Abstract: A communication system is provided, which includes a power amplifier, a receive-end filter, an ADC, an output simulation circuit, and a predistortion circuit. The power amplifier amplifies a RF input signal to generate a RF output signal. The RF input signal is generated according to a baseband signal. The receive-end filter filters a feedback signal generated according to the RF output signal to output a filtered feedback signal. A bandwidth of the filtered feedback signal is at least 3 to 5 times a bandwidth of the RF input signal. The ADC converts the filtered feedback signal to a digital input signal. The output simulation circuit generates, according to the digital input signal and the baseband signal, a reference signal simulating the RF output signal. The predistortion circuit builds a predistortion model according to the reference signal.

Abstract: A method and apparatus provide equal energy codebooks for coupled antennas with transmission lines. A plurality of precoders can be received from a codebook in a transmitter having an antenna array. Each precoder of the plurality of precoders can be transformed to a transformed precoder such that the transmit power for each transformed precoder is equal to the transmit power for each of other transformed precoders of the plurality of precoders. The transmit power can be expressed as a quadratic form with respect to the corresponding precoder. The quadratic form can be based on a transmission line impedance of a transmission line between a signal source and the antenna array. A signal can be received from the signal source. A transformed precoder of the plurality of transformed precoders can be applied to the signal to generate a precoded signal for transmission over a physical channel. The precoded signal can be transmitted.

Abstract: A method and device for power adjustment in a user equipment and a base station are disclosed in the present disclosure. The user equipment receives first information which is used to trigger a first operation, and then receives K piece(s) of target information and transmits a first wireless signal. A transmission power value of the first wireless signal is a first power value; the first power value is irrelevant to all piece(s) of target information received prior to triggering the first operation. The K piece(s) of target information is(are) received after triggering the first operation. The sum of K power offset value(s) is used to determine the first power value. The K power offset value(s) are respectively indicated by the K piece(s) of target information.

Abstract: A massive multiple-input multiple-output (MIMO) robust precoding transmission method under imperfect channel state information (CSI), wherein the imperfect CSI obtained by the base station (BS) side of the massive MIMO system is modeled as an a posteriori statistical channel model including channel mean and channel variance information. The model considers the effects of channel estimation error, channel aging and spatial correlation. The BS performs the robust precoding transmission by using the a posteriori statistical channel model, so that the universality problem of the massive MIMO to various typical moving scenarios can be solved, and high spectral efficiency is achieved.

Abstract: A first branch group circuit includes a first branch circuit receiving a first RF input signal and first control information; and a second branch circuit receiving the first input signal and second control information. Each of the first and second branch circuits includes a power amplifier. The second control information enables the second branch circuit to be switched on or off while the first branch circuit remains on. A second branch group circuit includes: a third branch circuit receiving a second RF input signal and third control information; and a fourth branch circuit receiving the second input signal and fourth control information. Each of the third and fourth branch circuits includes a power amplifier. The fourth control information enables the fourth branch circuit to be switched on or off while the third branch circuit remains on. A combiner combines output signals of the power amplifiers to produce an output signal.

Abstract: Apparatus and methods for beamforming communication systems with sensor aided beam management are provided. In certain embodiments, a beamforming communication system includes an antenna array including a plurality of antenna elements. The beamforming communication system further includes a plurality of signal conditioning circuits operatively associated with the antenna elements, one or more sensors that generate sensor data, and a beam management circuit that controls the signal conditioning circuits to manage beamforming. The beam management circuit provides beam management based on the sensor data.

Abstract: Systems and methods are described, and one method includes acquiring a frequency offset for a demodulator receiving one symbol rate in combination with acquiring another frequency offset for another demodulator, based on sweeping the other frequency offset until detecting a qualifying symbol pattern or acquiring the frequency offset for the demodulator receiving one symbol rate, whichever occurs first. Associated with acquiring the other frequency offset based on acquiring the frequency offset for the demodulator receiving one symbol rate, setting the other frequency offset includes adjusting the frequency offset for the demodulator receiving one symbol rate.

Abstract: Physical layer processing methods for network acquisition by remote nodes in wireless communication systems are described herein. New methods for wireless network discovery and synchronization by remote nodes are described herein that utilize spatial (e.g., antenna array) processing algorithms which may achieve enhanced functioning in challenging radio frequency environments, such as those containing interference and multipath distortion effects. These methods may include advantageous use of spatial whiteners and associated pluralities of adaptive beamformers to detect network reference and synchronization signals and estimate their parameters.

Abstract: A wireless transmitter comprises a massive transmit antennas arrangement, a set of modulators, an analog precoder, and a codebook storing candidate predefined beam configurations corresponding to specific phase pattern configurations of the analog precoder. Transmissions of frames by the wireless transmitter are performed by using combinations of concurrent beam configurations stored in the codebook.

Abstract: Apparatus and methods related to multipath bandpass filters with passband notches are provided herein. In certain configurations, a multipath bandpass filter includes multiple filter circuit branches or paths that are electrically connected in parallel with one another between an input terminal and an output terminal. The input terminal receives an input signal, and each filter circuit branch includes a downconverter that downconverts the input signal to generate a downconverted signal, a filter network that generates a filtered signal by filtering the downconverted signal, and an upconverter that upconverts the filtered signal to generate a branch output signal. The filter network includes at least one low pass filter and at least one notch filter to provide a passband with in-band notches. The branch output signals from the filter circuit branches are combined to generate an output signal at the output terminal.

Abstract: Methods, systems, and devices for wireless communications are described in which measurements of a number of beams that are transmitted from a first device, measured at a second device are provided in a beam switch metric report from the second device. The beam switch metric report may provide the first device with information that is otherwise unavailable to the first device and that may be used for setting beam management parameters.

Abstract: A circuit may include a transmitter for generating a signal indicative of input data, an on-chip channel for transmitting the signal from the transmitter, and a receiver comprising a receiving terminal that has a negative resistance value as input resistance of the receiving terminal, the receiver generating a signal indicative of recovered data based on the transmitted signal through the on-chip channel. The circuit may recycle a portion of charge stored in the on-chip channel using charge recycling, and the charge recycling is associated with the negative resistance value of the input resistance.

Abstract: A transition detector includes a first integrator configured to provide a first integral signal by integrating a first training pattern signal according to a first compensation clock signal, a second integrator configured to provide a second integral signal by integrating the first training pattern signal according to a second compensation clock signal, and a third integrator configured to provide a third integral signal by integrating the first training pattern signal according to a third compensation clock signal, wherein occurrence of a transition of the first training pattern signal is detected when the first integral signal and the second integral signal are larger than, and the third integral signal is smaller than, a first reference voltage.