Pulse or digital communications – Repeaters – Testing
Patent
1995-03-07
1997-09-02
Chin, Stephen
Pulse or digital communications
Repeaters
Testing
375230, 375232, 375233, H04B 1500, H04K 100, H04L 2730
Patent
active
056639830
ABSTRACT:
A differentially matched filter for spread spectrum or code division multiple access communication systems comprises a delay line, a multiplication stage, two adders, and an additional delay element. In one embodiment, the delay line comprises elements of delay T with taps therebetween connected to respective elements of the multiplication stage. In another embodiment, the delay line comprises elements of delay T/M with taps after each Mth element connected to respective elements of the multiplication stage. The multiplication stage is connected to a first adder connected in turn to a first input of a second adder. The output of the second adder is the output of the filter and is also connected through the additional delay element to a second input of the second adder, to produce an output sequence. Also disclosed is a method of filtering spread signals at a receiving side of a transmission system comprising the steps of fixing a received sequence of spread signals in a delay line; multiplying successive or predetermined values of the received sequence by respective weighting coefficients constituting a second code sequence that is a replica to a first code sequence used for coding a base band signal at a transmitting side of the system; adding together products of the multiplication, to produce an output sequence; delaying the output sequence for a time of delay equal to delay of one element of the delay line to produce a delayed output sequence; and adding the output sequence to the delayed output sequence.
REFERENCES:
patent: 4016410 (1977-04-01), Eggermont
patent: 5224123 (1993-06-01), Iga et al.
patent: 5418817 (1995-05-01), Richter
patent: 5436928 (1995-07-01), Fukuawa et al.
patent: 5499268 (1996-03-01), Takahashi
"Spread Spectrum Communications" by M.K. Simon, J.K. Omura, R.A. Scholtz, and B.K. Levitt, vol. III, 1 printed by Library of Congress Cataloging in Publication Data 1985, pp. 66-75.
"Simplified Matched Filter Receiver Design for Spread Spectrum Communications Application" by G.J.R. Povey and P.M. Grant, Electronics & Comm. Engineering Journal, Apr. 1993, pp. 59-64.
"Digital Communications and Spread Spectrum Systems" by R.Z. Ziemen and R.L. Peterson, 1985, pp. 385-387.
Chin Stephen
Ghayour Mohammad
Industrial Technology Research Institute
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