A method of operating a signal processing apparatus (110) comprises receiving a first signal representing a received data bit, determining from the first signal a first soft data bit, storing the first soft data bit in a leaky storage device (130), receiving a second signal representing the received data bit, and determining from the second signal a second soft data bit. The stored first soft data bit is read from the leaky storage device (130), an elapsed leakage time of the stored first soft data bit is measured, and a third soft data bit is generated dependent on the stored first soft data bit read from the leaky storage device (130) and on the elapsed leakage time. A fourth soft data bit is generated by combining the second soft data bit and the third soft data bit, and the received data bit is decoded dependent on the fourth soft data bit and on a selected plurality of further received data bits.

A transmitter (110), a receiver (120) and a method (700) for communicating data packets. The method (700) comprises receiving (701) a data packet and determining (702) if it is a re- or new transmission; and, when it is a retransmission: combining (703) the received (701) data packet with oldest unsuccessfully decoded data packet stored in a second memory (850), and decoding (704) the combined (703) data packet; when it is a new transmission: decoding (704) the received (701) data packet; checking (705) if the decoding (704) is successful; deleting (706) the oldest stored data packet in the first memory (840); storing (707) the decoded (704) data packet in the first memory (840) when the decoding (704) is successful or storing (707) the decoded (704) data packet in the second memory (850) when the decoding (704) is not successful; and transmitting (708) feed-back information to the transmitter (110).

Hybrid ARQ is employed in a multi-carrier communication system for retransmission of erroneous packets by taking advantage of time/frequency/space diversity and by combining ARQ functions at physical layer and MAC layers, making the multi-carrier system more robust in a high packet-error environment.

Aspects of the disclosure provide an apparatus that includes a receiving circuit and a baseband processing circuit. The receiving circuit is configured to receive signals transmitted from another apparatus to the apparatus and generate digital samples in response to the received signals. The received signals have a plurality of frequency sub-bands allocated as transmission resources. A specific frequency sub-band is allocated to the apparatus to carry data and control information to the apparatus. The baseband processing circuit is configured to receive the digital samples, process the digital samples to generate symbols in the respective frequency sub-bands, and decode the symbols in the respective frequency sub-bands to determine the specific frequency sub-band that is allocated to the apparatus.

Systems and methods are disclosed for performing hybrid automatic repeat request (HARQ) for grant-free uplink transmissions. Some of the systems and methods disclosed herein may address problems such as how to perform acknowledgement (ACK) and/or negative acknowledgement (NACK), how to determine and signal retransmission timing, how to determine the transmission/retransmission attempt and the redundancy version (RV), and/or how to perform the HARQ combining.

A user apparatus communicates with a base station in a mobile communication system which includes cells including a first cell and a second cell which uses a TTI different from that of the first cell, includes a reception unit with a buffer for, in the case where decoding of downlink data received from the base station has failed, storing the downlink data in the buffer, and combining the downlink data stored in the buffer and retransmitted data transmitted from the base station based on acknowledgment information for the downlink data, and decoding the combined result; and a transmission unit for transmitting the acknowledgment information for the downlink data to the base station. The reception unit includes a buffer control unit for dividing the buffer with a dividing number based on the TTIs of the first and second cells, and storing the downlink data in divided areas of the buffer.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive, from a base station, an indication of a first search space for control messages from the base station, an indication of a first downlink beam for the first search space, an indication of a second search space for control messages from the base station, and an indication of a second downlink beam for the second search space. The UE may monitor the first search space, using a spatial filter based at least in part on the first downlink beam, for an initial transmission of data from the base station. Additionally, the UE may monitor the second search space, using a spatial filter based at least in part on the second downlink beam, for re-transmission of the data from the base station. Numerous other aspects are provided.

The present disclosure provides methods and apparatus for detecting when a data transmission has been preempted or punctured by detecting inconsistency in the modulation or other signal characteristic of a received signal. If an inconsistency is detected, measures can be taken to mitigate potential problems caused by the inconsistent data. In one example, the receiving device (30) may identify soft bits in a soft buffer that may have been corrupted and flush the corrupted parts from the soft buffer.

A user equipment (UE) is described. The UE includes receiving circuitry configured to receive a radio resource control message including first information used for configuring a number of more than one code block groups (CBGs) in a transport block (TB). The receiving circuitry is also configured to receive the more than one CBGs, the more than one CBGs comprising first CBGs and second CBGs. The UE also includes processing circuitry configured to determine a number of code blocks (CBs) from the TB. A first number, a second number, a third number, and a fourth number are given based on the number of more than one CBGs and the number of CBs. The first number is a number of the first CBG(s). The second number is a number of CB(s) comprised of each of the first CBG(s). The third number is a number of the second CBG(s). The fourth number is a number of CB(s) comprised of each of the second CBG(s).

The present disclosure relates to a 5G or pre-5G communication system which will be provided in order to support a higher data transmission rate than in 4G communication systems such as LTE. A method at a relay node according to one example of the present invention is a hybrid automatic repeat request method at the relay node in a relay wireless communication system using a compress-and-forward (CF) scheme, and may comprise the steps of: when receiving data from a previous node, performing mesh quantization so as to have redundant information at the time of quantization for transmitting, to a next node, the data received from the previous node; transmitting to the next node by channel-coding only an amount transmittable to a channel set for transmitting to the next node from upper information among the quantized information; and when receiving negative acknowledgement (NACK) from the next node, retransmitting to the next node by channel-coding only an amount transmittable to the set channel among the other information which is not transmitted among the quantized information.