摘要:
Control signalling for systems employing link adaptation and incremental redundancy is described. A link adaptation/incremental redundancy message can be transmitted from a receiving entity to a transmitting entity to inform the transmitting entity of the receiving entity's incremental redundancy status or preference. Another message, which indicates whether resegmentation should be performed for retransmitted blocks can also be transmitted from a receiving entity to a transmitting entity. Both of these messages can be used by the transmitting entity to determine an appropriate modulation/coding scheme for subsequent transmissions of both original data blocks and retransmitted data blocks. The messages can be used together or independently in either link (uplink or downlink) between a base station and a mobile station in a radiocommunication system.
摘要:
An apparatus and method for recursive filtering of time discrete measurement data relating to a measurable time-varying attribute to generate an estimated magnitude for the attribute at a particular time instant. Each measurement has an associated reliability indicator representing a relative reliability of the measurement. Using the individual reliability indicators and a time-weighted filtered reliability indicator for a prior time instant, a filtered reliability indicator for the current time instant is generated. The filtered reliability indicator for the current time instant is then used to reliability-weight a weighted average of the plurality of measurements and to reliability-weight a time-weighted estimated magnitude for the prior time instant. The weighted values are then used to generate an estimated magnitude of the time-varying attribute for the current time instant.
摘要:
A wireless communications system, transmitter, receiver and method are provided that are capable of supporting incremental redundancy error handling schemes using available gross rate channels. More specifically, the transmitter includes a coding circuit for coding a digital data block and generating a mother code word, and a reordering circuit for reordering the mother code word and generating a reordered mother code word. The transmitter also includes a modulating circuit for modulating at least one subsequence each of which has a desired number of bits taken from the reordered mother code word to fill the available bandwidth of at least one available gross rate channel. The transmitter continues to forward the modulated subsequences to the receiver until the receiver successfully decodes the digital data block.
摘要:
In a telecommunications system, such as a cellular radio telecommunications system, transmission information, such as modulation scheme selection information, coding information or power level control commands, is efficiently conveyed from the transmitter to the receiver without increasing the bandwidth requirements and without introducing additional transmission delays. This can be accomplished by employing a data symbol phase rotation technique, wherein a sequence of data symbols, for example, a sequence of training symbols used for estimating the propagation characteristics of a given channel, are phase-rotated in accordance with a phase rotation factor that uniquely corresponds to the information being conveyed to the receiver. At the receiver, the symbols are de-rotated until the receiver recovers the training sequence. This allows the receiver to determine the phase rotation factor used to rotate the symbols at the transmitter. This, in turn, identifies the corresponding transmission information.
摘要:
A Decision Feedback Sequence Estimator (DFSE) metric is determined by storing one or more tables of Decision Feedback Estimation (DFE) hypotheses in a memory, and then using values of the DFE hypotheses that are retrieved from storage to determine the DFSE metric. The DFE hypotheses may be precalculated and stored into the memory prior to performance of any retrieval operation. Alternatively, the table may start out empty, and the DFE hypotheses may be determined as needed for a particular DFSE metric computation. The determined DFE metric may then be stored into a table for later retrieval if the metric is needed again. The DFE hypotheses may be stored into a single table or, to reduce memory requirements and computational complexity, may be stored into corresponding ones of plural tables. MLSE hypotheses, which are also used in the DFSE metric determination, may similarly be stored into one or more tables for later retrieval as needed.
摘要:
The present invention relates to a method and an arrangement for demodulating data symbols (d1-dN) having been transmitted through a communication channel, particularly a channel suffering from one or more impairments. Received signal samples ({overscore (&rgr;)}), representing the sent data symbols (d1-dN), are stored (310) and demodulated in both the forward (320) and the backward direction (330), via a demodulator/equaliser. In course of the demodulations are produced a first (SF) and a second (SB) respective set of soft values (skF; skB), which each is associated with a certain data symbol (dk). (340) From every pair of soft values (skF; skB) is then determined a joint soft value (SkJ), which e.g. may be utilised for deriving a resulting set of data symbols ({circumflex over (d)}1-{circumflex over (d)}N) or for directly decoding the payload information contained in the data symbols (d1-dN).