Embodiments can provide a precoding matrix indicating method, a precoding matrix determining method, a receive end device, and a transmit end device. In the precoding matrix indicating method, component matrices of an ideal precoding matrix and a weight of each component matrix can be determined based on at least one basic codebook. A dimension of each component matrix is the same as a dimension of the ideal precoding matrix, and a column vector of each component matrix is selected from column vectors of one of the at least one basic codebook. A precoding matrix indicator can be sent. The precoding matrix indicator can indicate the component matrices and the weight of each component matrix. With this, an ideal precoding matrix is approximately represented in a form of a weighted sum of a plurality of component matrices so that feedback overheads caused by feeding back a precoding matrix can be reduced.

Provided is a frame configuration usable for both SISO transmission and MISO and/or MIMO transmission. A frame configurator of a transmission device configures a frame by gathering data for SISO and configures a frame by gathering data for MISO and/or MIMO data, thereby to improve the reception performance (detection performance) of a reception device.

A multipath communication system forms a complex weighted compound signal for transmission through a channel environment wherein the compound signal includes a complex variable weighted compound signal related to a count of available antennas, a power constraint related to each said antenna, and a channel state characteristic.

Provided is a frame configuration usable for both SISO transmission and MISO and/or MIMO transmission. A frame configurator of a transmission device configures a frame by gathering data for SISO and configures a frame by gathering data for MISO and/or MIMO data, thereby to improve the reception performance (detection performance) of a reception device.

A transmission method for transmitting a first modulated signal and a second modulated signal in the same frequency at the same time. Each signal has been modulated according to a different modulation sheme. The transmission method applies precoding on both signals using a fixed precoding matrix, applies different power change to each signal, and regularly changes the phase of at least one of the signals, thereby improving received data signal quality for a reception device.

Provided is a precoding method for generating, from a plurality of baseband signals, a plurality of precoded signals to be transmitted over the same frequency bandwidth at the same time, including the steps of selecting a matrix F[i] from among N matrices, which define precoding performed on the plurality of baseband signals, while switching between the N matrices, i being an integer from 0 to N?1, and N being an integer at least two, generating a first precoded signal z1 and a second precoded signal z2, generating a first encoded block and a second encoded block using a predetermined error correction block encoding method, generating a baseband signal with M symbols from the first encoded block and a baseband signal with M symbols the second encoded block, and precoding a combination of the generated baseband signals to generate a precoded signal having M slots.

Precoding coefficients can be compressed based on user equipment signal interference to noise ratio or path loss in front haul cloud radio access network systems. For example, a baseband unit can compute a precoder matrix from an estimated channel associated with an uplink signal. Once the baseband unit computes the channel, it can determine the coefficients for the linear combination of the basis vectors, which are known at the baseband unit and the radio unit as well. The baseband unit can estimate the path loss and the signal interference to noise ratio and determine the basis vectors. The baseband unit can then compress the coefficients and transmit the coefficients to the radio unit. When the radio unit receives the compressed coefficients, the radio unit can reconstruct the precoder matrix and apply to reference signals and data traffic channels.

Methods and systems are provided for transmitting data using an orthogonal pules shape multiplexing scheme. A transmitter can receive a vector comprising a plurality of symbols. A plurality of continuous pulses can be designed, with each of the continuous pulses corresponds to one of the plurality of symbols in the received vector. Any two pulses selected from the plurality of continuous pulses can be orthogonal. The plurality of continuous pulses can be sampled to produce a corresponding plurality of discrete pulses. The received vector can be transformed based on a transform matrix constructed using on the plurality of discrete pulses. The transformed vector can be transmitted to a receiver.

A method implemented in a base station used in a wireless communications system is disclosed. The method comprises having 1-layer, 2-layer, 3-layer, and 4-layer codebooks for 4 transmit antenna (4TX) transmission, each codebook including a plurality of precoding matrices, precoding data with one of the plurality of precoding matrices, and transmitting, to a user equipment, the precoded data, wherein each of the 1-layer and 2-layer codebooks comprises a first codebook and a second codebook, and wherein each precoding matrix in the first codebook comprises a first index and a second index. Other apparatuses, systems, and methods also are disclosed.

The invention relates to an encoder for encoding a vector comprising channel state information and/or a pilot sequence, the encoder comprising a determining unit configured to determine a cell of a sphere mesh, wherein the cell includes the vector, a mesh refinement unit configured to determine a refined sphere mesh based on an initial sphere mesh, and a representation unit configured to determine a binary representation of a first identifier of an initial cell of the initial sphere mesh that includes the vector and a second identifier of a refined cell of the refined sphere mesh that includes the vector.