公开(公告)号：EP1157475B1

公开(公告)日：2008-07-16

申请号：EP00903326.7

申请日：2000-01-18

Applicant: Silicon Laboratories, Inc.

Inventor： OKUNEV, Yuri ,  DRUCKER, Vitaly ,  WANG, Qin ,  GOLDSTEIN, Yuri

IPC: H04B1/38 ,  H04B14/04 ,  H04L23/02 ,  H04L27/10 ,  H04L27/04 ,  H04L27/36 ,  H04L27/20 ,  H04L23/00 ,  H04J3/12

CPC classification number: H04J3/125 ,  H04B14/048 ,  H04L25/4927

Abstract: A method in a modem having a frame having a plurality of slots, for determining whether incoming DIL sequence information contains A-law or mu-law is provided. From the DIL sequence information, an ordered table of levels for each slot is generated. The levels of all non-robbed-bit slots are averaged, and average levels are subjected to an A-law/mu-law separation function. The separation function F1(n1,n2)=sum from i=n1 to i=n2 {L(i) - 2* [L(i-16]} effectively compares values of a first plurality of levels L(i) to twice the values of a second plurality of levels sixteen levels removed from the first plurality of levels (420). The sum is compared to a threshold (430), as the sum will be small for A-law values and large for mu-law values.