2619 results about "Retransmission" patented technology

Transmitters, receivers, and coding schemes to increase data rate and decrease bit error rate of an optical data link are disclosed. Data is transmitted across the link with a less than nominal bit error rate (BER), by encoding the data using a forward error correction (FEC) code or by requesting retransmission of transmitted packets in error. Data is transmitted at a speed that introduces errors at a rate that is in excess of the nominal BER but that may be corrected using the FEC code or retransmission so that the data may be received with less than the nominal BER. The data rate is increased as the link operating speed is increased beyond the overhead required by the FEC codes or retransmission. High speed FEC encoders and decoders facilitating such transmission are disclosed.

The present invention relates to a method and system of transmissions and retransmissions of packet data in a communications system, where the communications system uses switched channels, switching between rates or channels of different characteristics, and connection control and management in such a system. Particularly, the invention relates to radio resource management in a Universal Mobile Telecommunications System, UMTS, or WCDMA system allowing for use of compatible protocols for non-switched and switched channels.

A method and device for determining a parameter (RTO) associated with a retransmission time-out feature in a data unit transmitter implementing a protocol (TCP) that provides an acknowledgment feature and a retransmission time-out feature, where according to one aspect decreasing values of the round trip time (RTT) are treated differently with respect to their influence on a mean deviation parameter (RTTVAR) than increasing values of the round trip time, where according to another aspect weight values (g, h, w) used in the determination of the parameter (RTO) are chosen such that at least one of them is time variable, and where according to a further aspect the parameter (RTO) is also calculated on the basis of a value (SR) indicative of the number of spurious time-outs in the communication.

The present disclosure includes systems and methods for direct packet communications and store and forward packet communications including packets which have attributes which determine the lifetime of the packet contents and these lifetimes are optionally a function of the recipient. Example methods are given featuring the transmission of packets with limited lifetime, the storing and retransmission of packets to one or more recipients and confirmation of deletion of packet contents. It is also shown that cryptography may be employed to ensure that timed presentation of packet contents to recipients takes place and is authenticated by the sender.

The invention relates to a method for retransmitting a transmission unit (12) via an air interface in a wireless access system employing fragmentation for transmissions, wherein the available transmission capacity on said air interface is variable, and wherein said transmission unit (12) was transmitted a first time together with fragmentation information. In order to enable such a retransmission, it is proposed that the transmission unit (12) is retransmitted after a refragmentation with information FC, FSN on this refragmentation and with at least some of the fragmentation information FC′, FSN′, TSN that was transmitted before with said transmission unit (12) in the first transmission. The invention equally relates to a corresponding wireless access system and to a corresponding transmitting unit for such a wireless access system.

A wireless local area network includes transmission of data packets between endpoints in which packet frames are divided into sub-frames. On reception of a frame, the integrity of each individual sub-frame is checked. Sub-frames that pass the integrity check are acknowledged and retransmission is requested only for sub-frames that failed the integrity check. Consequently, only the affected sub-frames require retransmission instead of the whole frame.

An OFDM communication apparatus comprises subcarrier selecting means for selecting subcarriers to be transmitted for each branch in accordance with the number of retransmissions of transmitting signals and transmitting means for providing TIFFT processing to transmitting signals arranged in said subcarriers for each branch to transmit the resultant.

The invention discloses an embedded system capable of upgrading software on line and an online upgrading method. The system comprises an embedded terminal, and a remote master station, a short range master station and a local master station which can respectively transmit data with the embedded terminal, wherein the embedded terminal comprises a master control chip, a program memory, a data memory, a remote communication interface and a local/close communication interface; the program memory of the embedded terminal is divided into a region A and a region B which have equal structures, when the master station transmits a software package to the embedded terminal, a bootstrap process of a system of the embedded terminal is sequentially performed from the region A to the region B in turn, and a bootstrap region is converted when the software of the system is upgraded each time; and double backups of system program are saved in the program memory, and if the upgrading process is failed, the system program can be recovered from a region in which the system program is successfully started last time. By the method, various abnormal situations in the online upgrading process can be effectively identified, and corresponding measures are taken for repair, such as error retransmission, resume from break point, invalid abandon or failure recovery, so that the correctness and robustness of online upgrading can be ensured.

A transmission/reception method and apparatus for a mobile communication system supporting uplink MIMO is provided. In the transmission method, a User Equipment (UE) transmits two transport blocks according to a predetermined number of layers and respective precoding indices, an evolve Node B (eNB) transmits, when one of the transport blocks is lost, a negative acknowledgement for the lost transport block, and the UE sets a precoding index for the lost transport block to a predetermined value to retransmit the lost transport block while maintaining the number of layers.