Waveforms may be shaped in a wireless communications device by processing head tones of a multi-tone carrier using a head tone waveform shaping characteristic to provide a first sub-symbol, processing tail tones of the multi-tone carrier using a tail tone waveform shaping characteristic to provide a second sub-symbol, and processing center tones of the multi-tone carrier using a center tone waveform shaping characteristic to provide a third sub-symbol. The first, second, and third waveform shaping characteristics may be different from each other, i.e., the waveform shaping may be asymmetric. The first, second, and third sub-symbols may be combined to provide an output symbol.

Various methods and systems are provided for edge windowing of orthogonal frequency division multiplexing (OFDM) systems. In one example, among others, a method includes obtaining an edge windowing portion by reducing a cyclic prefix size for a quantity of edge subcarriers in an OFDM symbol and reducing side lobes by applying a windowing function to the edge subcarriers. In another example, a device includes a separator capable of dividing subcarriers of an OFDM symbol into first and second subcarrier groups, a first CP adder capable of obtaining a windowing portion by adjusting a cyclic prefix size of the first subcarrier group, and a first windower capable of reducing side lobes by applying a windowing function to the first subcarrier group. In another example, a method includes determining a RMS delay spread of a mobile station and scheduling a subcarrier based at least in part upon the RMS delay spread.

A semiconductor device capable of communicating with a host apparatus includes a symbol generation unit, a coding unit, and a transmission unit. The symbol generation unit includes a random number generation circuit and generates a symbol according to a random number generated by the random number generation circuit. The coding unit performs 8b/10b coding for the symbol. The transmission unit transmits the symbol coded by the 8b/10b coding unit to the host apparatus.

A processing module for a transmitter device configured to provide for generation of a signal comprising at least one frame for transmission by the transmitter device to a receiver device, the processing module configured to provide for processing of an input pulse stream comprising a stream of pulses representative of data, to provide an output pulse stream, each pulse of the pulse streams having one of two states defining the phase with which a carrier wave is modulated; the processing module configured to; divide the input pulse stream into consecutive groups of pulses; and for each group of pulses, based on determination that the first two or more consecutive pulses of the group have the same polarity, provide for addition of at least one dummy pulse to the group directly after the first two or more consecutive pulses, with an opposite polarity.

Embodiments of a noise-shaping crest factor reduction method for a carrier signal (and a device that performs the method) include (a) clipping the carrier signal by selecting at least one carrier signal peak that has a magnitude exceeding a predetermined crest factor reduction threshold, (b) subtracting the resulting clipped signal from the carrier signal, (c) confining, by a noise shaping filter, the resulting clipping noise signal in a frequency band corresponding to that of the carrier signal, and (d) subtracting the resulting spectrally shaped clipping noise signal from a delayed version of the carrier signal. The confining process includes selecting first sub-areas of the noise shaping filter response at one or more guard bands, selecting at least one second sub-area of the noise shaping filter response elsewhere in the frequency band, and setting the first sub-areas to a first predetermined magnitude higher than the magnitude of the second sub-area.

The present invention provides for an improved application of signal strength weightings in a SDMA sectorized cellular network. The improved signal strength weightings application is conducted through the improved selection of weightings from a new codebook subset or by the selection of weightings from a larger codebook subset. In a further embodiment, an antenna beam index or bit map can be used to select the best beam(s) in a SDMA sectorized cellular network. In another embodiment, a field or factor in an uplink or downlink transmission packet can designate which directional transmission beam is best suited for the transmission or when the directional transmission beam should be activated.

The present invention discloses a method and an apparatus to automatically remove crosstalk, which can automatically mask G.fast frequencies that will produce crosstalk between an existing transmission line and each port of a DPU/DSLAM equipment without unnecessary manual operation, to automatically remove crosstalk interference between G.fast and the existing transmission line, and is applicable for various generic interfaces. According to the present invention, the installation time is greatly reduced, human errors are also reduced, and the installation can be done correctly by ordinary technicians, which is advantageous to the promotion of G.fast systems.

Embodiments relate to a receiver (310) for receiving a multicarrier signal. The multicarrier signal comprises a first frequency block with a first group of subcarriers, the first frequency block being filtered with a first frequency block specific sideband suppression filter (106-1) for sideband suppression outside of said first frequency block, and at least a second frequency block with at least a second group of subcarriers, the second frequency block being filtered with a second frequency block specific sideband suppression filter (106-2) for sideband suppression outside of said second frequency block. The receiver (310) comprises a filter module (320) operable to perform an inverse sideband suppression filter operation for the first and at least the second frequency block.

A transmission apparatus includes a symbol arrangement unit to receive multiple symbols constituting a block, duplicate a first symbol of a block one block previous to the block, and output a block symbol being the present block with the duplicated duplicate symbol inserted at a first position thereof, a frequency conversion unit to convert the block symbol into a frequency domain signal, a frequency component removal unit to remove one or more frequency components from the frequency domain signal, a time conversion unit to convert, after interpolation on the frequency domain signal with the frequency components removed, the interpolated frequency domain signal into a time domain signal, and a cyclic prefix insertion unit to duplicate, in the time domain signal, a signal from a position based on the first position through an end as a cyclic prefix, and insert the cyclic prefix at a beginning of the time domain signal.

A plurality of information bits are mapped to: (i) a first plurality of constellation symbols corresponding to a first plurality of OFDM subcarriers in an OFDM symbol, and (ii) a second plurality of constellation symbols corresponding to a second plurality of OFDM subcarriers in the OFDM symbol. A first time-domain signal is generated by performing an IDFT based on the first plurality of constellation symbols. A second time-domain signal is generated by performing an IDFT based on the second plurality of constellation symbols. The first time-domain signal is modified by applying a first windowing function corresponding to a first transition width 1. The second time-domain signal by applying a second windowing function having a second transition width 2. An output signal is generated to include a sum of the first time-domain signal and the second time-domain signal, the output signal corresponding to the OFDM symbol.