Method, apparatus and system for eliminating aliasing noise in multi-carrier modulation system

摘要

A method, an apparatus and a system for eliminating aliasing noise in a multi-carrier modulation system are disclosed. The method includes: acquiring a first power spectrum density template; acquiring information of in-band subcarriers whose aliasing noise is greater than background noise, and acquiring a difference between the aliasing noise and the background noise of the in-band subcarriers; adjusting the first power spectrum density template according to the information of the in-band subcarriers and the corresponding difference to obtain a second power spectrum density template; and sending signals according to the second power spectrum density template. The method, the apparatus, and the system disclosed herein eliminate the aliasing crosstalk noise, improve the performance and stability of in-band services without involving upgrade or modification of the Customer Premises Equipment (CPE), and are easy to implement.

主权项

1. A method for eliminating aliasing noise in a multi-carrier modulation system, wherein: a range covered by frequency of subcarriers of the multi-carrier modulation system is divided into at least two non-overlapping bands which comprise a first band and a second band, each band comprises one or more subcarrier frequencies, and the method comprises:
acquiring a first power spectrum density template of the one or more subcarriers in the second band; acquiring carrier information of the one or more subcarriers in the first band; acquiring a number (N) of the one or more subcarriers in the first band that can carry bit data in the first band; acquiring background noise of an Nth subcarrier in the first band; acquiring a number (N) of the one or more subcarriers in the second band that can carry bit data in the second band; calculating crosstalk noise generated by the Nth subcarrier in the second band; acquiring the aliasing noise of the Nth subcarrier in the first band according to the calculated crosstalk noise of the Nth subcarrier in the second band and a preset aliasing attenuation coefficient; judging whether the aliasing noise of the Nth subcarrier is greater than the background noise of the Nth subcarrier, and, if so, calculating a difference between the aliasing noise of the Nth subcarrier in the first band and the background noise of the Nth subcarrier in the first band; adjusting the first power spectrum density template according to the carrier information of the one or more subcarriers in the first band and the corresponding difference to obtain a second power spectrum density template; and sending one or more subcarrier signals in the second band according to the second power spectrum density template.