A method of transmitting downlink data in a mobile communications system, wherein the mobile communications system comprises a base station configured to communicate wireless signals to one or more terminal devices. The method comprises receiving an indicator of a maximum number of downlink repetitions “Nmax” currently accepted by a terminal device, wherein a number of downlink repetitions indicates a number of times that the same signal is transmitted to the terminal device; setting an actual number of downlink repetitions “Ntx” so that the actual number of downlink repetitions meets the condition Ntx≤Nmax; and transmitting the downlink data, to the terminal device, wherein the downlink data is transmitted via a signal transmitted a number of times equals to the actual number of downlink repetitions.

A method in a packet-based network like the Internet is provided, which is directed towards packet loss recovery for transmission of a data stream, DS.sub.0 in a packet-based network. The method comprises transmitting data packets associated with the data stream, and upon receiving a retransmission request of missing data, retransmitting the missing data applying a selective retransmission of missing data, which may be based on a priority ranking of data types to be retransmitted, performing retransmission if it is determined that missing data will be received in time for display, or performing retransmission with a rate control.

A data transmitting method, includes: generating, by a first device, data messages based on a to-be-sent data stream; transmitting, by the first device, the data messages to a second device based on a packet transmission rate; recording, by the first device, the number of transmitted data messages; when the number of the transmitted data messages reaches a preset number for one batch, transmitting, by the first device, a verification message to the second device; receiving, by the first device, a verification acknowledgement returned by the second device, and determining, by the second device, a packet loss rate of the batch of data messages; updating, by the first device, the packet transmission rate based on packet loss rates of multiple batches of data messages.

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may adaptively switch between hybrid automatic repeat request (HARQ) monitoring modes to support power savings. In a first HARQ skipping mode, the UE may transmit an uplink message corresponding to a HARQ identifier and may receive a positive acknowledgment (ACK) message in a HARQ monitoring occasion associated with the HARQ identifier. Upon receiving the ACK message, the UE refrains from monitoring a subsequent HARQ monitoring occasion associated with the HARQ identifier while in the first HARQ skipping mode (e.g., an aggressive HARQ skipping mode). The UE may periodically enter a periodic evaluation mode from the first HARQ skipping mode, in which the UE monitors a subsequent HARQ monitoring occasion after receiving an ACK message to check for false ACK messages. If a false ACK message is detected, the UE enters a first HARQ skipping prohibited mode.

A method implemented in a first communication node for communicating with a second communication node over an acknowledged connection, comprising: receiving a stream of code blocks from the second communication node, wherein each code block is associated with a check value enabling error detection and belongs to a predefined group of code blocks; detecting errors in received code blocks using respective associated check values; and transmitting to the second communication node an acknowledgement in respect of each of said predefined groups of code blocks, wherein a negative value of the acknowledgment signifies that an error was detected for at least one of the code blocks in the predefined group, wherein the acknowledgement for a predefined group of two or more code blocks is based on a combination of error detection results for a subset of the code blocks in the predefined group.

There may be situations in which it is beneficial for a user equipment to switch between grant-free uplink wireless transmissions and grant-based uplink wireless transmissions. Systems and methods are disclosed that help facilitate grant-based and grant-free uplink wireless communications, and the switching between the two. For example, systems and methods for mitigating collision between a granted uplink wireless transmission and a grant-free uplink wireless transmission are disclosed herein.

Provided is a user equipment method of transmitting and receiving data in a wireless communication system, comprising receiving a request for a packet data convergence protocol (PDCP) data recovery from an upper layer, determining at least one PDCP packet data unit (PDU), previously submitted to a re-established radio link control (RLC) entity, for which a successful delivery has not been confirmed by a lower layer, and performing a retransmission of the determined at least one PDCP PDU.

A system and method for increasing reliability for media data distribution using an unreliable protocol within a network of devices is provided. A preemptive packet recovery (PPR) module is provided within a receiver to organize any correctly received payload packets and recover any missing payload packets using a plurality of forward error correction packets. The forward error correction packets include redundant payload data corresponding to the payload packets. If the PPR module is not able to recover a missing payload packet, the PPR module sends a Negative Acknowledgment (NACK) to the provider requesting that the provider resend the missing packet. The system relies on the recovery logic enabled by a packet reconstruction module to recover any missing packets and only requests the resending of missing packets when packets are not recoverable, thus maintaining the increased speed of UDP while increasing the reliability of the data being sent and received.

Systems and methods are described for streaming content to multiple devices from a shared sliding window buffer in kernel space, thereby reducing memory resource use and minimizing context/mode switching between kernel space and user space. For example, concurrent streaming sessions may be seen, e.g., as a live multimedia stream. If a live video is being transmitted as a multicast stream to many devices, rather than each device having a corresponding sliding window buffer in kernel space, each device will share a shared sliding buffer in kernel space. The sliding window buffer size will be at least large enough to stream the slowest connection speed and can be, e.g., multiple times as large as necessary, in case of the issues beyond the worst-case scenario. The system then transmits chunks of the content from the shared sliding window buffer to each of the plurality of client devices.

Devices, computer-readable media, and methods for selecting a type of packet loss protection for a network-based communication based upon a latency estimate are disclosed. For example, a processing system including at least one processor may obtain a latency estimate for a network-based communication, determine whether the latency estimate exceeds a latency threshold for selecting a type of packet loss protection, and select, the type of packet loss protection for the network-based communication from among a first type of packet loss protection and a second type of packet loss protection based upon the determining. When the latency estimate is determined to not exceed the latency threshold, the first type of packet loss protection is selected. When the latency estimate is determined to exceed the latency threshold, the second type of packet loss protection is selected.