A method and device for detecting a signal of an LTE uplink system in an interference condition. The method comprises: receiving baseband signals of M receiving antennas, and after fast Fourier transform, conducting demapping to obtain frequency-domain baseband signals; extracting a DMRS inserted in a received signal of each antenna, and then, calculating a channel gain h.sub.l,k of each receiving antenna; combining the baseband signals and the channel gains of the M receiving antennas to obtain a signal matrix Y.sub.k and a gain matrix H.sub.k; calculating an interference noise covariance matrix R.sub.k on each subcarrier; conducting interference pre-processing on a received signal on each combined subcarrier to obtain the received signal (1) and the channel gain (2) after the interference pre-processing, where D=R.sub.k.sup.−1/2; and according to (3), conducting frequency-domain balancing on the received signal after the interference pre-processing.

A method for receiving an Orthogonal Frequency Division Multiplexing (OFDM) signal transmitted by a user device in a wireless network comprises determining which subcarrier frequencies are allocated to the user device; converting the OFDM signal to a frequency-domain values corresponding to the subcarrier frequencies; and decoding the frequency-domain values to recover data symbols encoded by the user device on the subcarrier frequencies. The decoding employs codes that are inverse to, complex-conjugate of, or complementary to a set of complex-valued codes employed by the user device to shape the OFDM signal into a superposition of cyclic-shifted pulse waveforms, wherein each of the pulse waveforms has one of the data symbols modulated thereon.

A method of separating a desired signal from an undesired signal includes obtaining a total input signal comprising the desired signal and the undesired signal in a time domain occupying a time duration from time t.sub.1 to time t.sub.2 of a single symbol in the desired signal. A transform is performed of the total input signal wherein an output of the transform is a time domain signal representing the desired signal.

Embodiments of this application provide a signal transmission method and a communication apparatus in a multi-waveform scenario, and are applied to a scenario in which a single-carrier waveform and a multi-carrier waveform coexist. In this method, a network device indicates, via first indication information, a terminal device to transmit a signal by using transmission parameters corresponding to the first indication information, so that the terminal device transmits the signal by using the specified transmission parameters. Transmission parameters includes at least two of a transmission bandwidth, an extended bandwidth, or a total bandwidth. According to the embodiments of this application, a transmit end may perform sending by using the single-carrier waveform, and a receive end may perform receiving by using the multi-carrier waveform; or a transmit end may perform sending by using the multi-carrier waveform, and a receive end may perform receiving by using the single-carrier waveform.

A method performed by a communication node for transmission of a signal according to a single- or multiple carrier modulation scheme in a wireless communications network. The communication node modulates at least a first part of the signal into at least a first symbol with a shorter duration than a complete symbol according to the modulation scheme. The communication node modulates at least a second part of the signal into at least a second symbol with a shorter duration than a complete symbol according to the modulation scheme. The duration of the at least first and second symbols are equal to the duration of a complete symbol according to the carrier modulation scheme. Then, the communication node transmits the at least first and second symbol as a complete symbol according to the modulation scheme without time domain separation.

The present disclosure relates to a 5G or pre-5G communication system to be provided for supporting a higher data transmission rate beyond 4G communication systems such as LTE. A method for modulation in a transmitter for transmitting a signal in a wireless communication system according to an embodiment of the present invention comprises: a step for determining a modulation scheme; a step for, if the determined modulation scheme corresponds to a specific modulation scheme, converting encoded information bits to quadrature amplitude modulation (QAM) symbols in accordance with a predetermined QAM modulation order, selecting a sequence corresponding to an element of an integer vector in a predetermined sequence set, repeating the converted QAM symbols for a predetermined sequence length, and outputting signals by multiplying the repeated QAM symbols and the selected sequence; and a step for transmitting the outputted signals to a receiver.

A method for transmitting a signal is described, wherein the method has transforming a signal into a frequency domain to obtain a spectrum, forming a filtered spectrum according to a filter spectrum and occupying a set of subcarriers of a frequency domain representation of an Orthogonal Frequency Division Multiplex (OFDM) signal with the filtered spectrum. A temporary signal is obtained by transforming the frequency domain representation of the OFDM signal into a time domain. The temporary signal is subjected to a phase modulation.

A cooperative multi-user multiple input, multiple output (MIMO) antenna array comprises a MIMO subspace processing system communicatively coupled by a fronthaul network to a set of antennas residing on multiple ones of a plurality of geographically distributed wireless terminals in a Radio Access Network. The MIMO subspace processing system can comprise a distributed computing system. The MIMO antenna array is adapted by updating the set of antennas to produce a second set of antennas; reconfiguring the fronthaul network; selecting an updated set of distributed computing resources to perform MIMO subspace processing; and reconfiguring the MIMO subspace processing to employ channel state information of the second set to enable multiple non-interfering subspace channels occupying a common frequency.

Wireless communication techniques for transmitting and receiving reference signals is described. The reference signals may include pilot signals that are transmitted using transmission resources that are separate from data transmission resources. Pilot signals are continuously transmitted from a base station to user equipment being served. Pilot signals are generated from delay-Doppler domain signals that are processed to obtain time-frequency signals that occupy a two-dimensional lattice in the time frequency domain that is non-overlapping with a lattice corresponding to data signal transmissions.

Aspects relate to reconstructing a received non-linearly distorted (e.g., clipped) signal. A transmitting device may non-linearly distort a signal to be transmitted (e.g., by clipping peaks of the signal). A receiving device uses a signal reconstruction procedure to reconstruct the original signal. For example, the receiving device may estimate the non-linear distortion (e.g., due to clipped peaks) in the received signal by slicing the received signal, and applying a non-linear distortion to (e.g., clipping) the sliced signal using a threshold that corresponds to a threshold (e.g., a clipping threshold) used by the transmitting device. The receiving device may thereby generate a reconstructed signal based on this estimate of the non-linear distortion.