Communications: directive radio wave systems and devices (e.g. – With particular circuit – For correlation
Reexamination Certificate
2003-01-17
2004-12-21
Tarcza, Thomas H. (Department: 3662)
Communications: directive radio wave systems and devices (e.g.,
With particular circuit
For correlation
C342S194000, C342S195000
Reexamination Certificate
active
06833810
ABSTRACT:
TECHNICAL FIELD OF THE INVENTION
This invention relates generally to communications systems, and more specifically to combining signals exhibiting multiple types of diversity.
BACKGROUND OF THE INVENTION
Signals from multiple receivers may be combined to determine content included in the signals. Known techniques for signal combining, however, may not be able to combine signals that exhibit multiple types of diversity such as temporal, frequency, polar, or spatial diversity. Consequently, known techniques for signal combining are unsatisfactory in certain situations.
SUMMARY OF THE INVENTION
In accordance with the present invention, disadvantages and problems associated with previous techniques for combining signals may be reduced or eliminated.
According to one embodiment of the present invention, combining signals includes receiving first signals having a first frequency and second signals having a second frequency. A first weight reflecting a signal-to-noise ratio associated with a first signal is determined for each first signal, and a first signal output is generate from the first signals in accordance with the first weights. A second weight reflecting a signal-to-noise ratio associated with a second signal is determined for each second signal, and a second signal output is generate from the second signals in accordance with the second weights. The first signal output and the second signal output are combined to yield a combined signal output.
Certain embodiments of the invention may provide one or more technical advantages. A technical advantage of one embodiment may be that signals are combined in accordance with the signal-to-noise ratios associated with the signals, such that maximal ratio combining gain may be substantially realized. Accordingly, signals that exhibit multiple types of diversity such as temporal, frequency, polar, or spatial diversity may be combined.
Certain embodiments of the invention may include none, some, or all of the above technical advantages. One or more other technical advantages may be readily apparent to one skilled in the art from the figures, descriptions, and claims included herein.
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Bortnyk George P.
Lupia David J.
Baker & Botts L.L.P.
Raytheon Company
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