Space-time coded massive (STCM) and space-frequency coded (SFC) massive multiple-input multiple-output (MIMO) wireless communication systems and methods of making and using the same are disclosed. The STCM-MIMO system utilizes two massive MIMO antenna arrays that transmit data over two or more channel vectors to a user with at least one receive antenna. This configuration permits the system to use the asymptotic orthogonal qualities of massive MIMO pre-coding to eliminate the interference from other users' channel vectors and signals. The system also maintains the diversity of space-time codes to recover lost data through treating each transmitting massive MIMO array similarly to a 21 Alamouti space-time code. The STCM-MIMO wireless system can significantly outperform those using space-time coding techniques only. The SFC massive MIMO wireless system may be similar to the STCM-MIMO wireless system, except for the encoder block. In the exemplary SFC massive MIMO architecture, instead of spreading the code across the time slots, the code is spread across the subcarriers.

In this work, we present a novel receiving device design for communications systems that incorporates multiple antennas at the transmitting device/receiving device. Unlike existing systems, the new system does not require prior knowledge of the channel state information (CSI) at the receiving device side to extract the information symbols from the received signal. Consequently, complexity reduction and bit error rate improvement can be jointly achieved. Moreover, the new system may offer spectral efficiency enhancement since it does not require nulling to prevent the pilot symbols as in the case of conventional systems. The results obtained show that in certain scenarios the proposed system can offer up to 15 dB of bit error rate improvement over conventional systems. Moreover, the new system can provide about 16.6% of the spectral efficiency improvement.

Modulated signal A is transmitted from a first antenna, and modulated signal B is transmitted from a second antenna. As modulated signal B, modulated symbols S2(i) and S2(i+1) obtained from different data are transmitted at time i and time i+1 respectively. In contrast, as modulated signal A, modulated symbols S1(i) and S1(i) obtained by changing the signal point arrangement of the same data are transmitted at time i and time i+1 respectively. As a result the reception quality can be changed intentionally at time i and time i+1, and therefore using the demodulation result of modulated signal A of a time when the reception quality is good enables both modulated signals A and B to be demodulated with good error rate performances.

For example, a station may generate a plurality of space-time streams including at least a first space-time stream and a second space-time stream, the first space-time stream including, in a first interval, a first data sequence followed by a first Guard Interval (GI) sequence, the first space-time stream comprising, in a second interval subsequent to the first interval, a second data sequence followed by the first GI sequence, the second space-time stream comprising, in the first interval, a sign-inverted and time-inverted complex conjugate of the second data sequence followed by a second GI sequence, the second space-time stream comprising, in the second interval, a time-inverted complex conjugate of the first data sequence followed by the second GI sequence; and transmit a Single Carrier (SC) Multiple-Input-Multiple-Output (MIMO) transmission based on the plurality of space-time streams.

This application discloses a data sending method, a data receiving method, a device, and a system, and belongs to the field of communications technologies. The data sending method includes: precoding a plurality of spatial flows to obtain a plurality of precoded data streams, where the plurality of spatial flows include at least two first preprocessed spatial flows, and the at least two first preprocessed spatial flows are obtained by preprocessing a first original spatial flow; and transmitting the plurality of precoded data streams. This application resolves a problem of relatively low scheduling flexibility and improves scheduling flexibility. This application is used for data transmission.

Disclosed herein is a station (STA) device of a wireless LAN (WLAN) system. The STA device includes a radio frequency (RF) unit sending and receiving a radio signal and a processor controlling the RF unit. The processor may generate a physical protocol data unit (PPDU) including a physical preamble and a data field and send the PPDU using the RF unit.

This application provides a data transmission method and an apparatus. The method includes: obtaining, by user equipment, to-be-sent user data; performing, by the user equipment, channel encoding on the to-be-sent user data to obtain N sets of encoded data; performing, by the user equipment, codebook mapping on each of the N sets of encoded data by using a codebook, to obtain N sets of codebook-mapped data, where different sets of encoded data use codebooks that occupy mutually different non-zero physical REs, the non-zero physical RE means a non-zero waveform obtained after mapped data is mapped to a physical RE, and N is a positive integer greater than or equal to 2; and sending, by the user equipment, the N sets of codebook-mapped data to a base station.

A transmission method simultaneously transmitting a first modulated signal and a second modulated signal at a common frequency performs precoding on both signals using a fixed precoding matrix and regularly changes the phase of at least one of the signals, thereby improving received data signal quality for a reception device.

In an aspect of the present invention, a method for a user equipment to report channel state information (CSI) in a multi-antenna wireless communication system may include the steps of receiving first configuration information about a non-precoded first channel state information-reference signal (CSI-RS) configuration from a base station, receiving the first CSI-RS, reporting, to the base station, the first CSI generated based on the first CSI-RS, and reporting, to the base station, codebook configuration information about a codebook configuration which is a basis for generating the first CSI.

The present disclosure relates to a method and apparatus for beamformed transmission in a wireless local area network. According to one aspect of the present disclosure, a method for transmitting a Physical layer Protocol Data Unit (PPDU) frame to a plurality of stations (STAs) by an Access Point (AP) in a wireless local area network may be provided. The method may include transmitting a SIGNAL field of the PPDU frame, the SIGNAL field including beamforming information indicating whether beamforming is applied to respective data units of the PPDU frame, and transmitting the data units of the PPDU frame, the data units being individually beamformed or not beamformed according to the beamforming information.