A method and apparatus for allowing a UE to transmit uplink signals using a MIMO scheme are disclosed. In order to maintain good Peak power to Average Power Ratio (PAPR) or Cubic Metric (CM) properties when the UE transmits uplink signals using the MIMO scheme, the UE uses a precoding scheme based on a precoding matrix established in a manner that one layer is transmitted to each antenna in specific rank transmission.

The present disclosure provides a terminal device that allows constraints on user allocation to be prevented and spread codes to be allocated in a scheduler when non-adaptive HARQ is employed using a PHICH. A codeword generator generates code words by encoding data, a layer mapping unit places each CW in one or a plurality of layers, a DMRS generator generates a reference signal for each layer in which a CW is placed by using any resource among a plurality of resources defined by a mutually orthogonal plurality of OCCs, and an ACK/NACK demodulator receives a response signal indicating a retransmission request. When a response signal requesting retransmission of only a CW placed in a plurality of layers is received, the DMRS generator uses each resource having the same OCC among the plurality of resources for the reference signals generated in the corresponding layers.

Methods, systems, and devices for wireless communications are described. In some systems, a device, such as an internet of things (IoT) device, may include a configuration or software (e.g., in baseband) that is common for multiple applications of the device. In some aspects, the device may select a setting for at least some if not each of a set of parameters associated with or defining a device profile of the device based on an application of the device. The device may perform a mapping procedure to map the settings for the parameters associated with the device profile to one or more baseband configurations or baseband handles and the device may customize the baseband of the device using the one or more baseband configurations. As such, the device may operate or communicate using the baseband that is customized based on the device profile and application of the device.

An apparatus for mapping data in a wireless communication system. The apparatus includes circuitry for generating a precoding matrix for multi-antenna transmission based on a precoding matrix indicator (PMI) feedback from at least one remote receiver where the PMI indicates a choice of precoding matrix derived from a matrix multiplication of two matrices from a first code book and a second codebook. The apparatus further includes circuitry for precoding one or more layers of a data stream with the precoding matrix and transmitting the precoded layers of data stream to the remote receiver.

An apparatus for mapping data in a wireless communication system. The apparatus includes circuitry for generating a precoding matrix for multi-antenna transmission based on a precoding matrix indicator (PMI) feedback from at least one remote receiver where the PMI indicates a choice of precoding matrix derived from a matrix multiplication of two matrices from a first code book and a second codebook. The apparatus further includes circuitry for precoding one or more layers of a data stream with the precoding matrix and transmitting the precoded layers of data stream to the remove receiver.

The disclosed subject matter relates to employing modulation layer mapping to improve the performance of multiple-input and multiple-output (MIMO) communication systems. In one embodiment, a method comprises determining, by a device comprising a processor, codeword information in association with establishment of a wireless communication link with a network device of a wireless communication network, wherein the device and the network device are configured to communicate via the communication link using a MIMO communication scheme. The determining the codeword information comprises determining a code rate and determining a number of modulation indexes for the code rate based on signal-to-noise ratios respectively associated with channel layers included in the MIMO communication scheme. The method further comprises sending, by the device, the codeword information to the network device via a control channel of the wireless communication link.

The present disclosure provides a terminal device that allows constraints on user allocation to be prevented and spread codes to be allocated in a scheduler when non-adaptive HARQ is employed using a PHICH. A codeword generator generates code words by encoding data, a layer mapping unit places each CW in one or a plurality of layers, a DMRS generator generates a reference signal for each layer in which a CW is placed by using any resource among a plurality of resources defined by a mutually orthogonal plurality of OCCs, and an ACK/NACK demodulator receives a response signal indicating a retransmission request. When a response signal requesting retransmission of only a CW placed in a plurality of layers is received, the DMRS generator uses each resource having the same OCC among the plurality of resources for the reference signals generated in the corresponding layers.

The present invention provides a terminal device that allows constraints on user allocation to be prevented and spread codes to be allocated in a scheduler when non-adaptive HARQ is employed using a PHICH. A codeword generator (103) generates code words (CW) by encoding data, a layer mapping unit (108) places each CW in one or a plurality of layers, a DMRS generator (110) generates a reference signal for each layer in which a CW is placed by using any resource among a plurality of resources defined by a mutually orthogonal plurality of OCCs, and an ACK/NACK demodulator (102) receives a response signal indicating a retransmission request. When a response signal requesting retransmission of only a CW placed in a plurality of layers is received, the DMRS generator (110) uses each resource having the same OCC among the plurality of resources for the reference signals generated in the corresponding layers.

A method for adaptive coding and modulation. The method includes generating a set of mapping functions and transmitting a t.sup.th set of transmit symbols where 1≤t≤T and T is a maximum number of symbol transmissions. Transmitting the t.sup.th set of transmit symbols includes transmitting each transmit symbol in the t.sup.th set of transmit symbols. Each transmit symbol is transmitted by a respective transmitter. Transmitting each transmit symbol includes generating a t.sup.th set of mapped symbols, generating each transmit symbol from the t.sup.th set of mapped symbols, and transmitting each transmit symbol. Generating the t.sup.th set of mapped symbols includes applying a mapping functions subset of the set of mapping functions on a respective data vector. Each mapping function in the mapping functions subset depends on a respective mapped symbol in an r.sup.th set of mapped symbols where 0≤r≤T.

Apparatuses, methods, and systems are disclosed for determining a TPMI for a codebook set. One method includes receiving information indicating a transmission capability of a remote unit. The method includes determining a transmit precoding matrix indication based on a rank and a codebook corresponding to the transmission capability and the rank, wherein the transmit precoding matrix indication corresponding to a rank of one includes a maximum of five bits, and the transmit precoding matrix indication corresponding to a rank of two includes a maximum of four bits. The method includes transmitting the transmit precoding matrix indication to the remote unit.