Multiplex communications – Communication over free space – Combining or distributing information via time channels
Reexamination Certificate
2000-04-28
2008-03-25
Olms, Douglas (Department: 2661)
Multiplex communications
Communication over free space
Combining or distributing information via time channels
C375S134000
Reexamination Certificate
active
07349381
ABSTRACT:
A method of obtaining coarse synchronization in a frequency hopped/direct sequence spread spectrum (FH/DSS) time division multiple access (TDMA) data link network includes tuning the receiver to a first frequency used in the data link network. Then, signal strength of signals received on the first frequency during a sample time period is observed to obtain a sample energy pattern. An expected energy pattern during a time uncertainty window is determined based upon a known hopping pattern. Then, the sample energy pattern is compared to a first portion of the expected energy pattern, with the first portion of the expected energy pattern corresponding to a first time period within the time uncertainty window. A determination is then made as to whether the first time period is a coarse synchronization candidate based upon the comparison. If it is determined that the time period is a coarse synchronization candidate, one or more additional comparisons on different frequencies can be used to verify the hypothesis.
REFERENCES:
patent: 4267592 (1981-05-01), Craiglow
patent: 4937822 (1990-06-01), Weddle et al.
patent: 4970479 (1990-11-01), Landt et al.
patent: 5204855 (1993-04-01), Bebee et al.
patent: 5204856 (1993-04-01), Bebee et al.
patent: 5359595 (1994-10-01), Weddle et al.
patent: 5428647 (1995-06-01), Rasky et al.
patent: 5521533 (1996-05-01), Swanke
patent: 5563918 (1996-10-01), Waldschmidt et al.
patent: 5564097 (1996-10-01), Swanke
patent: 6490262 (2002-12-01), Hogger
Bernard Sklar, “Digital Communications Fundamentals and Applications”, 1988, PTR Prentice Hall, pp. 562-570.
Text book synchronization solutions for synchronization to a FH/DSS data link, “Principles of Secure Communication Systems”, pp. 148-173; D.J. Torrieri; Artech House; 1991.
Spread Spectrum Communications Handbook, Ch. 3, pp. 956-991; M. Simon, J. Omura, R. Scholtz and B. Levitt; McGraw-Hill, 1994.
Clark Stephen M.
Golubiewski Terry J.
Zogg Scott J. F.
Eppele Kyle
Jensen Nathan O.
Olms Douglas
Rockwell Collins
Wilson Robert W.
LandOfFree
Synchronization technique for spread spectrum frequency... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Synchronization technique for spread spectrum frequency..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Synchronization technique for spread spectrum frequency... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3967473