Abstract: A Wi-Fi radio distribution network (RDN) station is provided for use in a wireless communications network comprising a plurality of wireless stations. The Wi-Fi RDN station comprises a multiple-input-multiple-output (MIMO) receiving system configured to operate in accordance with a channel estimation MIMO receiving scheme; and a RDN connected to the MIMO receiving system. The RDN comprises at least one beamformer arranged to be fed by two or more antennas, wherein each of the beamformers includes a combiner configured to combine signals coming from a plurality of antennas associated with the respective beamformer into a single signal. The MIMO receiving system is configured to perform one or both of channel estimation using a single antenna or beamforming. Both channel estimation and beamforming may be based on one or more packets addressed to one or more wireless stations in the communications network other than the Wi-Fi RDN station.

Abstract: A method of operating a base station in a wireless communication system supporting Frequency-Quadrature Amplitude Modulation (FQAM) and Multi-Tone FQAM (MT-FQAM) is provided. The method includes determining a modulation scheme of data to be transmitted, and modulating the data according to the determined modulation scheme, wherein if at least one resource block is included in the data and if the at least one resource block is mapped to at least one tone in a distributed manner, the MT-FQAM scheme is selected, or if one resource block is included in the data and if the one resource block is mapped to at least one tone in a continuous manner, the FQAM scheme is selected, or if multiple resource blocks are included in the data and if the multiple resource blocks are mapped to at least one tone in a continuous manner, the MT-FQAM scheme is selected.

Abstract: The present invention provides a method and modem for adjusting a modulation mode. In embodiments of the present invention, a first modem generates indication information according to a current working first modulation mode, so that the first modem can send the indication information to a second modem through a data frame. Therefore, the second modem adjusts a current working second modulation mode of the second modem according to the indication information, so that the adjusted second modulation mode is consistent with the first modulation mode. Therefore, the problem of complex operations in the prior art, caused by that an operator configures a modulation mode of a second modem as a current working modulation mode of a peer modem, that is, a first modem, can be avoided, and efficiency of network deployment can be improved.

Abstract: Methods and apparatus are provided for adaptively selecting a communications mode in high frequency systems. A first dual-mode device having capabilities of using two or more high frequency communications modes, such as OFDM and SC modulation, may transmit a signal to a second dual-mode device with the same capabilities. The second dual-mode device may compute a channel characteristic associated with a high frequency communications channel and select an optimal high frequency communications mode. The second dual-mode device may transmit information indicative of the channel characteristic or the selected communications mode to the first dual-mode device. The first dual-mode device may select and operate using the optimal high frequency communications mode based on the information received from the second dual-mode device. The first and second dual-mode devices may communicate using the selected high frequency communications mode.

Abstract: Some demonstrative embodiments include devices, systems and/or methods of communicating a wireless orthogonal-frequency-division-multiplexing (OFDM) signal. For example, a wireless communication device may communicate a wireless communication OFDM signal including a plurality of data subcarriers carrying data, at least one pilot subcarrier carrying a reference, predefined, value, and a plurality of zero subcarriers, carrying a zero value, surrounding the pilot subcarrier and separating between the pilot subcarrier and the data subcarriers.

Abstract: Provided is a near field wireless communication apparatus that uses magnetic coupling and a method for operation of the apparatus, in which the magnetic coupling is used to transmit data or clock information with low power and high efficiency. A pulse generator of the near field wireless communication apparatus generates a pulse signal corresponding to transmission digital data to be transmitted. When the transmission digital data is “1,” the near field wireless communication apparatus modulates the data into the pulse signal and transmits the pulse signal. When the data is “0,” the near field wireless communication apparatus does not output the pulse.

Abstract: Individual multipath components of digital data symbols sent from a transmitter on at least two carrier frequencies generated from a common clock signal, are received (401) with individual delays and processed by a receiver unit having at least two fingers. Successive channel estimates are determined (402) from received symbols for each finger and each carrier, and an estimated frequency error is determined (404) for each finger and each carrier. A linear equation system is constructed (405), in which each determined frequency error is expressed as a function of a first variable indicative of frequency drift and a second variable indicative of frequency error caused by Doppler effect. The equation system is solved (406) to provide a solution with estimates of the first and second variables for each finger, and an estimated frequency drift is determined (407) from the solution and utilized (408) as feedback signal for adjusting receiver clock frequency.

Abstract: The present invention relates to a method by which a terminal feeds back channel state information for downlink transmission in a wireless communication system supporting multiple antennas. More specifically, the present invention comprises a step of transmitting a first precoding matrix index (PMI) and a second PMI for each sub-band, wherein a precoding matrix preferred by the terminal is instructed to combine the first PMI and the second PMI, and a precoding codebook in which a portion of a plurality of bits forming the second PMI is additionally used to form the first PMI is applied.

Abstract: In a method for generating an orthogonal frequency division multiplexing (OFDM) symbol to be included in a PHY data unit for transmission via a communication channel, wherein the OFDM symbol includes a plurality of OFDM tones, information bits to be included in the OFDM symbol are encoded to generate encoded information bits. The encoded information bits are parsed into a plurality of spatial streams. The spatial streams, or space-time streams generated from the spatial streams, are mapped to transmit chains using a plurality of spatial mapping matrices corresponding to the plurality of OFDM tones. Additionally, one of i) reordering OFDM tones before spatial mapping is applied, or ii) reordering OFDM tones after spatial stream mapping is applied and reordering spatial mapping matrices to match the reordered OFDM tones is performed. The OFDM symbol to be included in the PHY data unit is generated.

Abstract: A transmitter circuit feeds to a transmitter coil, every time transmission data changes in logical value, a current signal in pulse form having a positive or negative polarity that is alternately inverted in response to each change in logical value; and a receiver circuit inputs induction voltage signals each being double pulses having both positive and negative polarities, which have been induced in a receiver coil by the current signal fed to the transmitter coil, to demodulate the transmission data. The receiver circuit includes: an amplifier that amplifies the induction voltage signals of double pulses induced in the receiver coil; and a signal generating unit that, when detecting first single pulses in the induction voltage signals of double pulses amplified by the amplifier, sets up an insensitive period for second single pulses therein, to generate an output signal corresponding to the transmission data, based solely on the first single pulses.

Abstract: This disclosure provides a split-path equalizer and a clock recovery circuit. More particularly, clock recovery operation is enhanced, particularly at high-signaling rates, by separately equalizing each of a data path and an edge path. In specific embodiments, the data path is equalized in a manner that maximizes signal-to-noise ratio and the edge path is equalized in a manner that emphasizes symmetric edge response for a single unit interval and zero edge response for other unit intervals (e.g., irrespective of peak voltage margin). Such equalization tightens edge grouping and thus enhances clock recovery, while at the same time optimizing data-path sampling. Techniques are also disclosed for addressing split-path equalization-induced skew.

Abstract: Aspects of the present disclosure relate to techniques that may be utilized in networks with base stations and/or mobile devices that use large number of antennas or multi-dimensional arrays of antennas. According to certain aspects, a method for wireless communications is provided. The method may be performed, for example, by a base station and generally includes mapping N physical antennas arranged in at least two dimensions to K virtual antennas, wherein K is less than N, transmitting reference signals (RS) via the K virtual antennas, and receiving, from a user equipment, feedback based on the RS transmitted on the K virtual antennas.

Abstract: The present invention relates to performance improvement in a cell edge, particularly, to a method for selecting a precoder for a terminal in a multiple antenna system, wherein the method comprises: performing channel estimation for reference signals of a serving base station and another base station; determining a minimum singular value by using the channel estimation result; and if a complete collaborative feedback structure is used, feeding back a table of the determined, minimum singular value to the base stations.

Abstract: A diversity receiver includes a first receiving channel and a second receiving channel. The receiver also includes a baseband processor that computes a difference between the received signal strengths of the signals received from the first and second channels, wherein the processor disables the signal received from the second channel if the difference is greater than a first threshold value and a BER associated with the second receiving channel is greater than a BER threshold value, and disables the signal received from the first channel if the difference is less than the negative first threshold value and the bit error rate (BER) associated with the first channel is greater than the BER threshold value. The receiver further includes a bypass circuit coupled to an input of an amplifier and a RSSI circuit that provides a conduction path between the input and a ground when the RSSI circuit detects a blocker signal.

Abstract: A method and an apparatus are provided in an OFDM receiver for detecting and compensating for long echo. The method comprises a first pilot tone interpolation mechanism and a first window placement to filter a received OFDM symbol, a long echo channel detection coupled with a second pilot tone interpolation mechanism, a pre-echo and post-echo detection wherein the pre-echo condition is associated with a second new window placement, and both pre-echo and post-echo conditions place two time windows around a first peak channel response and a second peak channel response for channel estimation. The long echo is estimated by obtaining power spectra of a subset of subcarriers in one OFDM symbol, performing an inverse Fourier transform on the power spectra and determining the long echo by measuring the time between two peaks in the power profile.

Abstract: A communication apparatus comprises an inserter that inserts an element having a value of 0 or nearly 0 into a predetermined position of a modulated signal to generate inserted data; an operator that adds a pilot signal comprising a data series of which the elements at the positions corresponding to the predetermined positions in the modulated signal are multiplied by a first amplitude coefficient and the elements other than the elements multiplied by the first amplitude coefficient are multiplied by a second amplitude coefficient to the inserted data to generate a post-operation data; an IFFT unit that performs IFFT on the post-operation data; and a transmitter that generates a baseband signal based on the post-operation data on which the IFFT is performed and transmits a transmission signal generated from the baseband signal.

Abstract: One embodiment relates to a device. The device includes reception circuitry adapted to receive a data unit from a first node of a network and a confirmation message signal from a second node of the network. Analysis circuitry is adapted to determine a failure to correctly receive the data unit. Transmission circuitry is adapted to transmit a negative acknowledgement signal to the first node in case the analysis circuitry determines the data unit has not been correctly received and the confirmation message signal from the second node is received. Other methods and devices are also disclosed.

Abstract: A communications terminal may include: a plurality of antennas; and a selection circuit configured to select at least one antenna of the plurality of antennas as a transmit antenna for a transmission to a radio communications network, wherein a selection of the transmit antenna may be based on a selection criterion.

Abstract: A base station (102), comprising a first antenna (111) for transmitting a first pilot signal; a second antenna (112) for transmitting a second a pilot signal; a third antenna (113) for transmitting a third pilot signal; and a fourth antenna (114) for transmitting a fourth pilot signal. The base station is configured to transmit pilot signal power information for indicating power values to a user equipment (104), UE, receiving the pilot signal power information. The pilot signal power information comprises: a first power value corresponding to the first pilot signal, a second power value corresponding to the second pilot signal, a third power value corresponding to the third pilot signal, and a fourth power value providing information regarding at least two demodulation pilot signals.

Abstract: A method and apparatus are provided for providing improved spectrum efficiency by triggering a ranked transmission. In this regard, a method is provided that includes causing a configuration message to be transmitted to a mobile terminal, wherein the configuration message provides interpretation information for a frequency hopping flag bit. The method also includes determining a rank for a transmission. The method may include setting a rank indication in the frequency hopping flag bit of a downlink control message based on the determined rank of the transmission.