Methods, systems, and devices for satellite operations are described. A satellite communications system may include a transmitter that applies multiple spreading codes to a data signal to obtain multiple spread data signals. The transmitter may transmit the multiple spread data signals from multiple antenna elements in a composite signal. The satellite communications system may also include a receiver that receives the composite signal and applies multiple despreading codes to the composite signal to obtain multiple despread data signals. The receiver may combine the multiple despread data signals to obtain a combined data signal that corresponds to the data signal processed by the transmitter. To combine the multiple despread data signals, the receiver may estimate coefficients for each of the despread data signals.

Provided is a transmitter which improves the flexibility of SRS resource allocation without increasing the amount of signaling for notifying the cyclic shift amount. In the transmitter, with regard to each basic shift amount candidate group having a basic shift amount from 0 to N−1, a transmission control unit (206) specifies the actual shift amount imparted to a cyclic shift sequence used in scrambling a reference signal transmitted from each antenna port, said specification being performed based on a table in which cyclic shift amount candidates correspond to each antenna port, and based on setting information transmitted from a base station (100). With regard to basic shift amount candidates for shift amount X, the table differentiates between an offset pattern comprising offset values for cyclic shift amount candidates corresponding to each antenna port and an offset pattern corresponding to basic shift amount candidates of X+N/2.

The present disclosure relates to a communication method and system for converging a 5th-Generation (5G) communication system for supporting higher data rates beyond a 4th-Generation (4G) system with a technology for Internet of Things (IoT). The present disclosure may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety services. The present invention presents a method for efficiently estimating a physical channel and, according to the present invention, a terminal of a communication system receives a synchronization signal from a base station, receives a broadcast channel from the base station, and can estimate the broadcast channel on the basis of the synchronization signal.

A base station transmits a layered data signal to multiple devices that are in close proximity to each other where the layered data signal includes at least first data on a first data layer directed to a first device and second data on a second data layer directed to a second device. The base station also transmits a single control message to both devices where the control message comprises location dependent control information directed to both devices. The control message also comprises data layer control information arranged in multiple fields where data layer control information in a field is associated with a device and allows the associated device to recover the data from a data layer assigned to the device.

A base station transmits a layered data signal to multiple devices that are in close proximity to each other where the layered data signal includes at least first data on a first data layer directed to a first device and second data on a second data layer directed to a second device. The base station also transmits a single control message to both devices where the control message comprises location dependent control information directed to both devices. The control message also comprises data layer control information arranged in multiple fields where data layer control information in a field is associated with a device and allows the associated device to recover the data from a data layer assigned to the device.

A system and method for identifying at least one aggressor cell are described. The method comprises transmitting at least one subframe from at least one base station of a first set of base stations to a second set of base stations, wherein the at least one subframe further comprises of at least one downlink subframe, at least uplink subframe and at least one special subframe. The second set of base stations decodes the at least one received subframe, and maps each of the at least one received downlink subframe, at least one received uplink subframe and at least one received special subframe of the at least one received subframe to at least one expected subframe. Lastly, at least one aggressor cell is determined based on a mismatch of the at least one received subframe and the at least one expected subframe.

In a multiuser (MU) multiple antenna system (MAS), a central processing unit is communicatively coupled to multiple distributed wireless terminals (WTs) via a network. The central processing unit processes channel measurements indicative of channel conditions between the multiple distributed WTs and a plurality of user devices and selects a plurality of WTs from the multiple distributed WTs to enhance channel space diversity within the MU-MAS. The central processing unit calculates (Multiple Input, Multiple Output) MIMO weights from the channel measurements for precoding a plurality of data streams that are transmitted concurrently from the plurality of WTs to the plurality of users, wherein the MIMO weights provide for a plurality of independent MIMO channels.

In an example method, a first device determines a first Zadoff-Chu sequence having a first root value, and a second Zadoff-Chu sequence having a second root value, where the first root value is an inverse modulus of the first root value. Further, the first device generates a wireless signal including (i) a first preamble generated based, at least in part, on the first Zadoff-Chu sequence, (ii) a second preamble generated based, at least in part, on the second Zadoff-Chu sequence, and (iii) a payload. Further, the first device transmits the wireless signal from the first device to a second device.

A method apparatus and system for efficiently transmitting and receiving channels are provided in a wireless communication system based on Orthogonal Frequency Division Multiplexing (OFDM). A multiplexing scheme differs according to a channel when a transmitter transmits a packet data channel, a common control channel and a control channel designated for a particular user. Uncoded 1-bit information is broadly dispersed in frequency and time domains using multiplexing technology for maximizing diversity gain in a channel for transmitting information of at least one bit to a particular user like an acknowledgement (ACK) channel. The transmitter converts a sequence obtained by multiplexing multiple bits to be transmitted to a plurality of users to parallel signals, and broadly disperses the parallel signals in the time and frequency domains. When the uncoded 1-bit information is transmitted, reception reliability is improved because channel coding and transmission are efficiently performed using a small amount of resources.

A transmitting apparatus is disclosed. The transmitting apparatus includes an encoder to perform channel encoding with respect to bits and generate a codeword, an interleaver to interleave the codeword, and a modulator to map the interleaved codeword onto a non-uniform constellation according to a modulation scheme, and the constellation may include constellation points defined based on various tables according to the modulation scheme.