| 摘要 |
A method of providing a high bit rate DMT signal includes providing information on a plurality of DMT tones, with at least two of the plurality of DMT tones sending information in parallel. Of the tones sending information in parallel, at least one has a SNR too low to be individually used for the number of bits it is transmitting. Accordingly, the tones are coherently "combined" at the receiver in order to generate a SNR sufficient together to carry, at the desired BER, the number of bits being transmitted in parallel. Two or more tones which alone cannot carry a single bit of information may be used together to provide a sufficient SNR at the receiver to transmit one or more bits. Similarly, two or more tones which alone cannot carry two bits of information, may be used together via parallel transmission to provide a sufficient SNR at the receiver. Further, the bit-carrying capacity of a first tone which can carry one or more bits may be increased by transmitting an increased number of bits in parallel with one or more additional tones which cannot carry any bits of information. According to another embodiment of the invention, rather than sending two or more DMT tones in parallel, one or more DMT tones are repeated over a plurality of DMT symbols, and "combined" coherently in order to generate a SNR sufficient together to carry the number of bits being carried by the repeated tone. |
