Patent ID: 6744824
Filing Date: 2004-06-01
Classification: H04L

Abstract:
A multiple access method for use in a communications network wherein a central station (CS) is coupled to a plurality of network terminals (T1, . . . , Ti, . . . , Tn) in a point to multipoint way via the cascade connection of a common link (L) and respective individual network terminal links (L1, . . . , Li, . . . , Ln), said method includes a step of allocating a respective unique variable (&rgr;1, . . . , &rgr;i, . . . , &rgr;n) to each respective network terminal of said plurality (T1, . . . , Ti, . . . , Tn), said method includes a first filtering operation on at least one oversampled symbol which is derived from upstream information to be transmitted by a terminal (T1;Ti) of said plurality to said central station (CS), said method includes a next step of filtering a received oversampled symbol stream at said central station (CS) for enabling said central station to discriminate therefrom said at least one oversampled symbol that was earlier transmitted by said network terminal (T1;Ti) to said central station (CS),characterized in that said first filtering operation comprises an all-pass filtering operation of said at least one oversampled symbol, said all-pass filtering operation having a z-transform transfer function ({overscore (c)}i(z)) such that the zeroes thereof correspond to said respective unique variables assigned to all other network terminals, except the unique variable (&rgr;1;&rgr;i) assigned to said network terminal (T1;Ti), said next step of filtering comprises performing the z-transform on said received oversampled symbol stream, and evaluating said z-transform at the unique variable (&rgr;1;&rgr;i) assigned to said network terminal (T1;Ti).