摘要:
A system and method to measure channel quality in terms of signal to noise ratio for the transmission of coded signals over fading channels. A Viterbi decoder metric for the Maximum Likelihood path is used as a channel quality measure. This Euclidean distance metric is filtered in order to smooth out short term variations. The filtered or averaged metric is a reliable channel quality measure which remains consistent across different coded modulation schemes and at different mobile speeds. The filtered metric is mapped to the signal to noise ratio per symbol using a threshold based scheme. Use of this implicit signal to noise ratio estimate is used for the mobile assisted handoff and data rate adaptation in the transmitter.
摘要:
A system and method to measure channel quality in terms of signal to interference plus noise ratio for the transmission of coded signals over fading channels in a communication system. A Viterbi decoder metric for the Maximum Likelihood path is used as a channel quality measure for coherent and non-coherent transmission schemes. This Euclidean distance metric is filtered in order to smooth out short term variations. The filtered or averaged metric is a reliable channel quality measure which remains consistent across different coded modulation schemes speeds. The filtered metric is mapped to the signal to interference plus noise ratio per symbol using a threshold based scheme. Use of this implicit signal to interference plus noise ratio estimate is used for the mobile assisted handoff in a cellular system, power control and data rate adaptation in the transmitter.
摘要:
A system and method of implementing a radio link protocol and dynamic partial echo management for a transaction oriented packet data communication system. A data backlog is described with a media access control layer controller and transmitting a BEGIN protocol data unit transmitted to a receiver. A media access control layer transaction is initiated in response to the transmitting of the BEGIN frame.
摘要:
A method and communication device for media access control feedback over a packet channel divided in channel time slots is provided. The channel time slots are divided into sub-channel time slots. A packet channel feedback field associated with each sub-channel time slot is defined. Acknowledgments are indicated using the packet channel feedback field. An active mobile identity associated with an active mobile station may be assigned which would then be included in the packet channel feedback field. A plurality of active mobile identities may be assigned and some of the active mobile identities may be reserved for special functions. The assigned active mobile identity is used, among other things, to identify an active mobile station to receive packet data signals. The active mobility identity is invalidated after one transaction of packet data signals or invalidated after a short number of such transactions. One or more of the assigned active mobile identities may be used to indicate a time slot assignment for the active mobile station. A sub-channel feedback field in the packet channel feedback field is used to indicate acknowledgments. A sub-channel assignment field in the packet channel feedback field is used to indicate time slot assignments. The sub-channel assignment field is substantially independent of the sub-channel feedback field.
摘要:
A system and method is provided for communicating in a wireless communication system which supports link adaptation or link adaptation and incremental redundancy. The invention provides link adaptation at multiple code rate by dividing fixed length RLC blocks into coded sub-blocks. CRC code may be appended to the RLC blocks for error detection. The sub-blocks are then grouped into transmission units for transmission. The number of sub-blocks in each group is varied to provide multiple code rates. Headers are used to identify the transmission units being transmitted. In the case of retransmission, the transmission units may be expressly identified through extended headers. One or more of the originally transmitted sub-blocks are dropped and replaced by the extended headers in the retransmission. Accordingly, the present invention provides for a retransmission code rate which may be different from the code rate at which the transmission units were originally transmitted.
摘要:
A system and method for incremental redundancy transmission in a communication system. A time slot is provided having at least one sub-slot with a fixed size, and a data block sized to fit in the sub-slot, a header having a one data block sequence number in the header for the time slot. A parity block is sized smaller than the data block such that the parity block and the data block sequence number fit within the sub-slot. The data block and parity block are transmitted in the sub-slot within the time slot. In the header for the time slot the number of data blocks and parity blocks transmitted are identified.
摘要:
A system and method of implementing a radio link protocol completion oriented packet data communication system. A data backlog is described with a media access control layer controller and transmitting a BEGIN protocol data unit containing a flag transmitted to a receiver. A media access control layer transaction is initiated in response to the transmitting of the BEGIN protocol data unit.
摘要:
A system includes a generator component that determines a plurality of portions that comprise an entirety of error-indicating acknowledgement information. The system includes a generator component that cycles through the plurality of portions that comprise the entirety of the error-indicating acknowledgement information to send the error-indicating acknowledgement information.
摘要:
The retransmission of signaling messages that data terminals (e.g., modems) might exchange prior to exchanging user data is controlled by arranging a data terminal that receives multiple copies of the same signaling message so that it saves only the first copy thereof, but transmits a response to the sending terminal following receipt of each such copy. The sending terminal terminates its transmission of the signaling message upon receipt of a response from the receiving terminal. The inventive procedure is especially advantageous for controlling the retransmission of signaling messages during a n-way handshake between two terminals.
摘要:
The throughput of a radio transmission link is enhanced by arranging a transmitter of data packets so that it responds to the transmission window closing by repeatedly retransmitting all unacknowledged data packets and doing so until the window reopens or a receiver status message acknowledges receipt of a retransmitted data packet.