A MIMO basestation for a cellular communications system comprises a remote indoor processing facility coupled to an outdoor RF tower via optical fibers. The remote indoor processing facility includes a bank of RF modulators to modulate signal streams; a remote MIMO transmitting processor that includes a remote digital beam-forming network to transform the modulated signal streams into transmit beam signals; a pre-processor to perform a wavefront multiplexing transform on the transmit beam signals to generate wavefront multiplexed beam signals, each of the wavefront multiplexed beam signals being a linear combination of the transmit beam signals; and RF-to-optical drivers to perform optical modulating functions on the wavefront multiplexed beam signals to generate optical waveform streams.

A side information transmission method and apparatus, where data to be transmitted by a transmit end includes at least one first data sub-block and at least one second data sub-block. A first modulated signal is obtained based on a first phase rotation factor. A second modulated signal is obtained based on a second phase rotation factor. Side information is generated based on the first phase rotation factor and the second phase rotation factor. The first data sub-block is carried on a first subcarrier, and the side information is also mapped to the first carrier. The first modulated signal corresponding to the at least one first data sub-block, the second modulated signal corresponding to the at least one second data sub-block, and a modulated signal corresponding to the side information are superposed to obtain a to-be-transmitted signal.

A system and method of DFT-S-OFDM modulation is provided that uses a set of frequency domain patterns. For a given transmitter, for a set of DFT-S-OFDM symbols, the frequency domain pattern changes according to a time domain hopping pattern. Advantageously, the time domain hopping patterns are defined to allow only a certain amount of overlap, for example for only one DFT-S-OFDM symbol, between any two time domain hopping patterns. This functions to reduce the effect of a collision, when two transmitters use the same frequency pattern, they will do so only for part of the overall transmission. Optionally, frequency domain spectral spreading is used in the transmitter. This can further reduce the PAPR. In the receiver, successive interference cancellation may be employed to reduce the effect of colliding transmissions.

A terminal device (2) according to the present disclosure includes a control unit (203). The control unit (203) acquires, from a base station apparatus (1), information about a signal waveform for use, of a plurality of signal waveforms including a single carrier signal, the signal waveform for use being used for downlink communication with the base station apparatus (1), the information being transmitted by using a predetermined signal waveform of the plurality of signal waveforms. The control unit (203) performs the downlink communication with the base station apparatus (1) by using the signal waveform for use, on the basis of the information.

A method for measuring channel quality in a wireless transceiver is disclosed, comprising: receiving, at a wireless transceiver, an analog signal from a user equipment (UE); converting the analog signal to a plurality of digital samples at an analog to digital converter (ADC); performing a fast Fourier transform (FFT) on the plurality of digital samples to generate frequency domain samples; identifying an uplink demodulation reference signal (DMRS) symbol; performing channel estimation on the DMRS symbol to identify an estimate of channels; creating a noise covariance matrix from the estimate of channels; and deriving an interference measure from the noise covariance matrix.

A leakage detection instrument may receive an electromagnetic signal radiated from a leakage location within a cable network system. The instrument may determine the leak based on spectral analysis and without the use of tagged or test signals.

A transmitting method includes: configuring a frame using a plurality of orthogonal frequency-division multiplexing (OFDM) symbols, by allocating time resources and frequency resources to a plurality of transmission data; and transmitting the frame, wherein the frame includes a first period in which a preamble which includes information on a frame configuration of the frame is transmitted, and a second period in which the plurality of transmission data are transmitted by at least one of time division and frequency division, and among the plurality of OFDM symbols, OFDM symbols included in the second period include pilot symbols arranged along a time axis with a predetermined spacing therebetween, and a predetermined number of data symbols.

An apparatus performs a discrete Fourier transform process on M×N received signal components included in a received signal, by a unit of N received signal components; and estimates an estimated signal containing M×N estimated signal components, which are estimated values of M×N transmission signal components, on the basis of the received signal on which the discrete Fourier transform process is performed. When the estimated signal xe is newly estimated, the apparatus performs an exclusion operation of excluding an estimated value xe.sup.(k) of the M transmission signal components that constitute a k-th transmission signal group from the estimated signal xe newly estimated, and updates the estimated value xe.sup.(k) based on an intermediate signal xt.sup.(k) obtained by the exclusion operation and the received signal, thereby re-estimating the estimated signal xe.

A method of controlling a signal power of a received signal received by a wireless communication device, the method including: measuring the signal power of the received signal at a plurality of time points in response to a gain control signal; calculating a variance of the signal power of the received signal at at least some time points of the plurality of time points; and controlling the signal power of the received signal based on a gain level determined according to the variance of the signal power of the received signal.

A transmitter in a wireless communication network comprises a Carrier Interferometry (CI) coder and a multicarrier modulator communicatively coupled to the CI coder. The CI coder encodes a plurality of data symbols with a plurality of CI codes to produce a plurality of CI symbol values, wherein each of the plurality of CI symbol values equals a sum of information-modulated CI code chips. Each information-modulated CI code chip equals a CI code chip multiplied by one of the plurality of data symbols. The modulator modulates each CI symbol value onto a different subcarrier frequency to produce a multicarrier signal.