Telephonic communications – Substation or terminal circuitry – Conversion of signal form
Reexamination Certificate
2005-02-08
2005-02-08
Isen, F. W. (Department: 2644)
Telephonic communications
Substation or terminal circuitry
Conversion of signal form
C379S387020, C379S399010, C379S399020, C379S398000, C379S413020, C379S413030, C379S413040
Reexamination Certificate
active
06853724
ABSTRACT:
Cascade low-pass filters are useful in attenuating the xDSL band in a POTS splitter. The design of the low-pass filter is a sixth-order filter having two stages. A first stage includes a fourth-order filter, preferably with a stop-band frequency of approximately 48 kHz. A second stage includes a second-order filter in cascade with the fourth-order filter. For this filter, the stop-band frequency is preferably approximately 29 kHz. The inductance value of the second stage is relatively small in comparison to the inductance values of the first stage. In this manner, improvements in xDSL band attenuation are facilitated with little or no eroding of the voice band performance such as insertion loss, pass-band attenuation and return loss.
REFERENCES:
patent: 4447679 (1984-05-01), Kojima et al.
patent: 4620069 (1986-10-01), Godwin et al.
patent: 4766402 (1988-08-01), Crane
patent: 4791659 (1988-12-01), Ross
patent: 4823383 (1989-04-01), Cardot et al.
patent: 5195232 (1993-03-01), Frederick
patent: 5528630 (1996-06-01), Ashley et al.
patent: 5539820 (1996-07-01), Pistilli
patent: 5559854 (1996-09-01), Suzuki
patent: 5598455 (1997-01-01), Bliven et al.
patent: 5623543 (1997-04-01), Cook
patent: 5757803 (1998-05-01), Russell et al.
patent: 5764727 (1998-06-01), Toumani et al.
patent: 5883941 (1999-03-01), Akers
patent: 5956385 (1999-09-01), Soto et al.
patent: 5974139 (1999-10-01), McNamara et al.
patent: 6067316 (2000-05-01), Amrany et al.
patent: 6069899 (2000-05-01), Foley
patent: 6137880 (2000-10-01), Bella
patent: 6144399 (2000-11-01), Manchester et al.
patent: 6144735 (2000-11-01), Bella
patent: 6178080 (2001-01-01), Wilken et al.
patent: 6192109 (2001-02-01), Amrany et al.
patent: 6201227 (2001-03-01), Tomita
patent: 6208637 (2001-03-01), Eames
patent: 6259676 (2001-07-01), Kellock et al.
patent: 6278769 (2001-08-01), Bella
patent: 6282204 (2001-08-01), Balatoni et al.
patent: 6285754 (2001-09-01), Sun et al.
patent: 6295343 (2001-09-01), Hjartarson et al.
patent: 6298037 (2001-10-01), Sharifi
patent: 6301337 (2001-10-01), Scholtz et al.
patent: 6314102 (2001-11-01), Czerwiec et al.
patent: 6324212 (2001-11-01), Jenness
patent: 6373923 (2002-04-01), Williamson et al.
patent: 6424627 (2002-07-01), Sorhaug et al.
patent: 6470046 (2002-10-01), Scott
patent: 6477238 (2002-11-01), Schneider et al.
patent: 6496566 (2002-12-01), Posthuma
patent: 6532216 (2003-03-01), Tennyson
patent: 6574309 (2003-06-01), Chea, Jr. et al.
patent: 6584148 (2003-06-01), Zitting et al.
patent: 6621831 (2003-09-01), Linz
patent: 20010033650 (2001-10-01), Wilson et al.
patent: 0317852 (1989-05-01), None
patent: 0814620 (1997-12-01), None
patent: 0891067 (1999-01-01), None
patent: 0909102 (1999-04-01), None
patent: 0923221 (1999-06-01), None
patent: 1117217 (2001-07-01), None
Budak, ARAM, Passive and Active Network Analysis and Synthesis, Page(s) 543-545, Publisher: Houghton Mifflin Company, Published in: Boston, MA. 1974.
Williams, Electronic Filter Design, , vol. Chapter 3, No. 3-1 to 3-7, Publisher: McGraw-Hill Book Company, Published in: Chapter 8, 8-9 to 9-20, 1981.
ADC DSL Systems Inc.
Fogg and Associates LLC
Isen F. W.
Powers Jon M.
Singh Ramnandan
LandOfFree
Cascade low-pass filter to improve xDSL band attenuation for... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Cascade low-pass filter to improve xDSL band attenuation for..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cascade low-pass filter to improve xDSL band attenuation for... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3473773