Multiplex communications – Generalized orthogonal or special mathematical techniques – Particular set of orthogonal functions
Reexamination Certificate
2001-03-26
2002-05-28
Marcelo, Melvin (Department: 2663)
Multiplex communications
Generalized orthogonal or special mathematical techniques
Particular set of orthogonal functions
C370S343000, C370S482000
Reexamination Certificate
active
06396803
ABSTRACT:
BACKGROUND OF THE INVENTION
Wireless communication systems have typically selected like transmission processes for both upstream and downstream carrier signals. In these systems, therefore, a single selection is chosen as a trade-off between cost and effectiveness and such trade-offs have not generally realized optimum utilizations of existing communication technologies.
SUMMARY OF THE INVENTION
The present invention is directed to wireless communication methods and structures that enhance communication robustness while reducing cost. These goals are realized by communicating downstream data with orthogonal frequency division multiplexing (OFDM) transmission processes and upstream data with single carrier transmission processes.
This combination of transmission processes is configured with various signal modulations (e.g., quadrature phase shift keying (QPSK), m-ary phase shift keying (MPSK) and n-quadrature amplitude modulation (QAM)) to provide lower cost upstream communication from customer services equipments (CPEs) and more robust downstream communication from headends than has been achieved in conventional communication systems.
In system embodiments, signal diversity is enhanced by receiving communication signals with multiple antennas that are spatially separated and potentially have different polarizations to thereby enhance signal diversity. Signal diversity is further enhanced by combining the received signals in ways that maximize the ratio of desired to undesired signals.
The novel features of the invention are set forth with particularity in the appended claims. The invention will be best understood from the following description when read in conjunction with the accompanying drawings
REFERENCES:
patent: 5282222 (1994-01-01), Fattouche et al.
patent: 5379289 (1995-01-01), DeSouza et al.
patent: 5485456 (1996-01-01), Shtayer et al.
patent: 5524023 (1996-06-01), Tsujimoto
patent: 5548582 (1996-08-01), Brajal et al.
patent: 5613191 (1997-03-01), Hylton et al.
patent: 5933421 (1999-08-01), Alamouti et al.
patent: 5953311 (1999-09-01), Davies et al.
patent: 5973642 (1999-10-01), Li et al.
patent: 6011799 (2000-01-01), Kerstein et al.
patent: 6088398 (2000-07-01), Wahlqvist et al.
patent: 6091932 (2000-07-01), Langlais
Hornsby James J.
Kelkar Kris
California Amplifier, Inc.
Koppel, Jacobs Patrick & Heybl
Marcelo Melvin
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