摘要:
A power control system in a TDMA radio communication system has traffic channels which are associated with a set of speech/channel encoding modes. Each mode has a different mix of speech encoder bit rate and data protection bit rate but the same total available gross bit rate. The transmitter includes a power control unit that replaces a mode allocated to a channel by another mode having either a higher or a lower data protection bit rate and either a lower or a higher speech encoder bit rate if the sound to be encoded requires either a lower or a higher speech encoding bit rate. The power control unit also controls a power adjustment unit that either reduces or increases the output power of the transmitter to a lower or a higher level such that an estimated decoded speech quality measure at the receiver is substantially constant.
摘要:
Techniques for discontinuous transmission (DTX) and fast in-band signaling of configuration changes and protocol messages in speech communications systems provide cost efficiency in terms of radio transmission capacity, in terms of fixed line transmission, and in terms of implementation effort. An exemplary method for performing discontinuous transmission (DTX) in a communications system in which source data is interleaved for transmission from a first component in the system to a second component in the system includes the steps of detecting periods of source data inactivity, and transmitting silence descriptor (SID) frames from the first to the second component during the periods of source data inactivity, certain of the transmitted SID frames being interleaved using a different interleaving algorithm as compared to that used for source data. For example, the source data can be block diagonally interleaved, and certain of the SID frames can be block interleaved. An exemplary method for effecting configuration changes in a communications system includes the step of transmitting an escape frame in place of a speech data frame, the escape frame including a gross bit pattern to distinguish the escape frame from speech data frames and conveying a configuration change indication. The escape frame can further include a data field to indicate a particular configuration change to be made. For example, where the communications system is an AMR system, an escape frame can be used to change an active codec mode set. Alternatively, an escape frame can be used to change a phase of codec information.
摘要:
In a radio communication system in a mobile to mobile call with one good (AMR102) and bad (AMR515) radio link, the good radio (AMR102) link is forced by the poor (AMR515) link to use a more robust AMR coded mode (AMR515) and thereby using excessive power (232). A capacity loss in such system is avoided by adjusting the power level (212) for the connection with the good link (AMR102).
摘要:
In a radio communication system in a mobile to mobile call with one good (AMR102) and bad (AMR515) radio link, the good radio (AMR102) link is forced by the poor (AMR515) link to use a more robust AMR coded mode (AMR515) and thereby using excessive power (232). A capacity loss in such system is avoided by adjusting the power level (212) for the connection with the good link (AMR102).
摘要:
The invention relates to a method and a device for avoiding interruptions in voice transmission in a cellular communication system. Voice data are thereby divided into segments, and the segments are associated with transmission quanta, so-called bursts. A number of segments is coded in a first transmission mode and is made available for transmission. Said first transmission mode is, for instance, for a transmission at full rate. Additional segments, which follow, are subsequently coded in a second transmission mode and are made available for transmission. The second transmission mode is, for instance, for transmission at half rate. Through the change from a first transmission mode to a second transmission mode, parts of the associated transmission quanta remain unused by applying the so-called interleaving. Said unused transmission quanta are used for performing additional functions, such as initiating a hand-over or FACCH signaling.
摘要:
A scalable decoder device (50) for signals representing audio comprises a primary decoder (21) connected to an input (40). The primary decoder (21) is arranged to provide a primary decoded signal (23) based on received parameters (4). A primary postfilter (31) is connected to the primary decoder (23) to provide a primary postfiltered signal (32). A secondary enhancement decoder (45) is connected to the input (40) and arranged to provide a secondary decoded enhancement signal (44). The device further comprises a combiner arrangement (55), arranged for combining the primary postfiltered signal (32) and a signal (53) based on the secondary decoded enhancement signal (44) into an output signal (6) to be provided at an output (6). The combining is made with an adaptable strength relation between contributions from the two signals. A method for decoding coded signals representing audio operates in analogy with the scalable decoder device (50).
摘要:
The invention relates to a method and an arrangement for encoding of signals in teleconferencing. The method involves receiving (502) signals from a plurality of nodes participating in a teleconference and analyzing (504) said signals. The method further involves appointing (506) one of the received signals as being a dominant signal and adapting (508) an encoder based on information related to the dominant signal. At least two of the received signals are mixed and then encoded (512), using the adapted encoder. The encoded mixed signal is then provided (514) to at least one of the nodes participating in the teleconference.
摘要:
Method and arrangement in a network node for adapting a property of source coding to the quality of a communication link in packet switched conversational services in a communication system. The method comprises obtaining (404) information related to the quality of a communication link. The method further comprises selecting (406) a source coding mode with an associated source coding delay, based on the obtained information and the associated source coding delay. The selected source coding mode is selected from a set of at least two source coding modes associated with different source coding delays, and is to be used when source coding voice data to be transmitted over the communication link.
摘要:
A network processing node (e.g., MGW, MRFP) and method are described herein that can: (1) receive packets on a first heterogeneous link (e.g., wireless link); (2) manipulate the received packets based on known characteristics about a second heterogeneous link (e.g., “Internet” link); and (3) send the manipulated packets on the second heterogeneous link (e.g., “Internet” link). For example, the network processing node can manipulate the received packets by adding redundancy, removing redundancy, frame aggregating (re-packetizing), recovering lost packets and/or re-transmitting packets.
摘要:
The present invention relates to an improved scheme for coding of audio. In particular, the present invention relates to an encoder device and a method for coding an input signal in an encoder system. The method comprises applying a first mode to the input signal to form a first output and applying a second mode to the input signal to form a second output. A first processed output is then formed from at least a part of the first output, and a second processed output is formed from at least a part of the second output. Forming a second processed output comprises estimating a part of the input signal from at least a part of the second output. Then, an optimum mode is determined based on the firstprocessedoutput and the secondprocessedoutput, and the output according to the optimum mode is selected.