摘要:
A system and method for improving bit-loading in discrete multitone (DMT)-based digital subscriber line (DSL) modems. In one embodiment, the system includes: (1) a model generator configured to generate a model containing a calculated total bit loading for an assumed gross coding gain and estimated total bit loadings for a other plurality of assumed gross coding gains and (2) a bit loader associated with the model generator and configured to load bits in accordance with the model.
摘要:
A method for changing the data rate over an interleaved latency path overcomes shortfalls of the ADSL2 seamless rate adaptation (SRA) and dynamic rate repartitioning (DRR). The interleaver depth is allowed to change during either a rate charge or rate repartioning so that the interleaver delay is constant before and after the change. The transmitter pauses its transmission for a time approximately equal to the delay of the interleaver so that there are approximately no errors introduced at the receiver.
摘要:
A method for Orthogonal Frequency Division Multiplexing Access (OFDMA) ranging is provided. The method includes receiving a signal having OFDMA symbols. An FFT is performed on this signal. Matching ranging codes are found. The power for a given hypothesized ranging code is determined and compared to a power threshold to determine if the code was transmitted. The timing offset and power are reported as the result of ranging.
摘要:
Improved approaches to provide flexibility in setting user data rates and managing delay in data transmission systems using a superframe structure and Time Division Duplexing (TDD) are disclosed. These improved approaches operate to provide intelligent insertion of dummy words (bits or bites) into a data stream to be transmitted. By inserting the dummy words, the invention is able to render codewords, symbols and superframes independent from user data rates. As a result, a wide range of user data rates are available in data transmission systems using a superframe and TDD.