The present application provides a spatial layered transmission method and a spatial layered transmission device. The spatial layered transmission method includes steps of: dividing to-be-transmitted data into at least two layers of spatial data; determining a symbol rate for each layer of spatial data, to enable an error between SERs for the layers of spatial data to be smaller than a predetermined error threshold; and encoding each layer of spatial data in accordance with the determined symbol rate, and transmitting the encoded layer of spatial data.

A decoder for determining an estimate of a vector of information symbols carried by a signal received through a transmission channel represented by a channel matrix is provided. The decoder includes a block division unit configured to divide the vector of information symbols into two or more sub-vectors, each sub-vector being associated with a block level; two or more processors configured to determine, in parallel, candidate sub-vectors and to store the candidate sub-vectors in a first stack. Each processor is configured to determine at least a candidate sub-vector by applying a symbol estimation algorithm and to store each candidate sub-vector with a decoding metric and the block level associated with the candidate sub-vector. The decoding metric is lower than or equal to a decoding metric threshold. A processor among the two or more processors is configured to determine at least a candidate vector from candidate sub-vectors stored in the first stack, the candidate vector being associated with a cumulated decoding metric and to update the decoding metric threshold from the cumulated decoding metric.

Systems and methods for OFDM channelization are provided that allow for the coexistence of sub-band channels and diversity channels. Methods of defining diversity sub-channels and sub-band sub-channels are provided and systematic channel definition and labeling schemes are provided.

A multiple-input multiple-output (MIMO) communication system that addresses three major challenges in airborne MIMO communications, namely, antenna blockage due largely to the movement and orientation of the airborne platforms, the presence of unknown interference inherent to the intended application, and the lack of channel state information (CSI) at the transmitter. The system is implemented on a Diagonal Bell-Labs Layered Space-Time (D-BLAST) MIMO architecture and includes spatial spreading to counter antenna blockage, temporal spreading to mitigate signal to interference and noise ratio degradation due to intended or unintended interference, and a simple low rate feedback scheme to enable real time adaptation in the absence of full transmitter CSI.

Multistream transmissions are provided for user equipment (UE) including a transceiver configured to receive an L-layer data transmission that includes at least one codeblock (CB). The CB includes a length-N cyclic redundancy code (CRC). The transceiver is also configured to receive a downlink control information (DCI) associated with the data transmission. The UE further includes a processor operably connected to the transceiver. The processor is configured to decode the data transmission, the CRC, and the DCI. The data transmission includes one codeword (CW) when L is less than or equal to a threshold and two CWs when L is greater than the threshold.

A multiple-input multiple-output (MIMO) communication system that addresses three major challenges in airborne MIMO communications, namely, antenna blockage due largely to the movement and orientation of the airborne platforms, the presence of unknown interference inherent to the intended application, and the lack of channel state information (CSI) at the transmitter. The system is implemented on a Diagonal Bell-Labs Layered Space-Time (D-BLAST) MIMO architecture and includes spatial spreading to counter antenna blockage, temporal spreading to mitigate signal to interference and noise ratio degradation due to intended or unintended interference, and a simple low rate feedback scheme to enable real time adaptation in the absence of full transmitter CSI.

A decoder for determining an estimate of a vector of information symbols carried by a signal received through a transmission channel represented by a channel matrix is provided. The decoder includes a block division unit configured to divide the vector of information symbols into two or more sub-vectors, each sub-vector being associated with a block level; two or more processors configured to determine, in parallel, candidate sub-vectors and to store the candidate sub-vectors in a first stack. Each processor is configured to determine at least a candidate sub-vector by applying a symbol estimation algorithm and to store each candidate sub-vector with a decoding metric and the block level associated with the candidate sub-vector. The decoding metric is lower than or equal to a decoding metric threshold. A processor among the two or more processors is configured to determine at least a candidate vector from candidate sub-vectors stored in the first stack, the candidate vector being associated with a cumulated decoding metric and to update the decoding metric threshold from the cumulated decoding metric.

Multistream transmissions are provided for user equipment (UE) including a transceiver configured to receive an L-layer data transmission that includes at least one codeblock (CB). The CB includes a length-N cyclic redundancy code (CRC). The transceiver is also configured to receive a downlink control information (DCI) associated with the data transmission. The UE further includes a processor operably connected to the transceiver. The processor is configured to decode the data transmission, the CRC, and the DCI. The data transmission includes one codeword (CW) when L is less than or equal to a threshold and two CWs when L is greater than the threshold.

Automatic retransmission in communications systems. In one embodiment, a portion of data is identified to be retransmitted based on feedback information indicating a negative acknowledgement (NACK) during a cyclic redundancy check (CRC) on a previous transmission of the portion of data. A retransmission mode is selected for the portion of data, from at least a first mode that retransmits the portion of data on at least a first transmitter antenna while transmitting new data on at least a second transmitter antenna, based on first desired transmission characteristics; and a second mode that retransmits the portion of data simultaneously on at least the first and second transmitter antennas, based on second desired transmission characteristics.

A method of serving a given data stream to a target mobile terminal, in a cellular communications network that includes a plurality of transmitting sites wherein each transmitting site including at least one antenna, is provided. The method includes designating at least two of the plurality of transmitting sites as cooperating sites; assigning tones to each transmitting site from a sub-band associated with the cooperating sites; dividing the data stream into at least two sub-data streams, each of the sub-data streams for transmission over selected tones; and interlacing tones of the cooperating sites in accordance with a selected one of a time switching and a frequency switching transmit diversity technique. Other techniques for multi-site MIMO cooperation are also provided.