Patents by Inventor Liqian Yao

Liqian Yao has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6760847
    Abstract: To identify interference from other data carrying subscriber loops (i.e., from loop disturbers), a power spectral density sample may be obtained from the subscriber loop under consideration based on at least one measurement while the loop is not transmitting data. The sample power spectral density may then be correlated with each one of a set of known power spectral densities. Each known power spectral density represents a power spectral density in a loop which is not transmitting data in the presence of one of (i) no subscriber loop disturbers, (ii) a particular subscriber loop disturber, and (iii) particular subscriber loop disturbers. Based on the correlations, subscriber loop disturbers may be recognized.
    Type: Grant
    Filed: April 13, 2000
    Date of Patent: July 6, 2004
    Assignee: Nortel Networks Limited
    Inventors: Gin Liu, Liqian Yao, Michael A. Campbell, Gary T. Stone
  • Patent number: 6181676
    Abstract: A radio communication network comprising a plurality of communication terminals and a plurality of repeaters intermediate the communication terminals, with wayside communication paths being established between pairs of the repeaters via two radio channels carrying the same data. Protection switching of a wayside path is determined, in a preferred embodiment, by using one common wayside path to calculate the FEC (Forward Error Correction) and PEC (Parity Error Count). Switching to the better of said two channels is effected if FEC or PEC exceed predetermined thresholds. The common wayside path is defined as follows: (a) &Sgr; wayside A path+&Sgr; wayside B path −&Sgr; (wayside A ||wayside B), if waysides A and B are overlapped (||indicates overlapped portions of the two parameters.) (b) wayside A path OR wayside B path, if waysides A and B are not overlapped.
    Type: Grant
    Filed: January 30, 1998
    Date of Patent: January 30, 2001
    Assignee: Nortel Networks Limited
    Inventors: Liqian Yao, Martin d'Anjou