摘要 |
In a multicarrier modulation system, the NTR signal is inserted and transported at the modulation layer by sending the NTR bits, for example, as specified in the ADSL standard, on a set of carriers of a specified DMT symbol in a superframe. For example, the NTR bits can be sent on the first DMT symbol of the superframe. Thus, for the other DMT symbols in the superframe, the set of carriers used for transporting the NTR can be used to transport other data, such as information data. |