Patent ID: 6714529
Filing Date: 2004-03-30
Classification: G01L,H04J

Abstract:
A digital signal demultiplexer having a band-separation filter bank comprising serially-connected 2-demultiplexing filter banks; whereina 2-demultiplexing filter bank comprises band-pass filters and down-samplers for culling sampling frequencies of filter output signals to 1/2; and when said 2-demultiplexing filter bank includes four types of filters designated as A, B, C and D in an ascending order in band-pass frequency fs, where fs is a sampling frequency of input signals into each 2-demultiplexing filter bank; then said 2-demultiplexing filter bank is either a first 2-demultiplexing filter bank containing at least filter A or filter B, or a second 2-demultiplexing filter bank containing at least filter C or filter D; and is connected to a next 2-demultiplexing filter bank such that signals processed through said filter A are processed in a next-stage by a first 2-demultiplexing filter bank in said next-stage; signals processed through said filter B are processed in said next-stage by a second 2-demultiplexing filter bank in said next-stage; signals processed through said filter C are processed in said next-stage by another first 2-demultiplexing filter bank in said next-stage; and signals processed through said filter D are processed in said next-stage by another second 2-demultiplexing filter bank in said next-stage.