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US 6,639,955 B1Granted
Generator for complex fading signals
AssigneeAgere Systems Inc.
InventorXiao-An Wang
Life of this patent
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AssigneeAgere Systems Inc.
InventorXiao-An Wang
Estimating the term…
A system employs a modified Jakes' fading model to generate a fading signal having substantially equivalent autocorrelation values for in-phase (I) and quadrature-phase (Q) components. A Walsh transform may be applied to generate multiple, uncorrelated I and Q components, for multiple fading signals. A complex Rayleigh fading signal according to the modified complex Jakes fading model is provided by a generator having M pairs of I and Q paths. Each pair of I and Q paths includes a corresponding complex carrier generator 201 (M an integer and 1≦n≦M) generating a complex carrier signal with frequency, ωn, where ωn is cos ((4n−3π)/4M). Each of the I paths has a circuit that separates the real component of the corresponding carrier signal to provide a real carrier signal cos (ωnt). Similarly, each of the Q paths has a circuit that separates the imaginary component of the corresponding complex carrier signal to provide an imaginary carrier signal sin (ωnt). The M output signals of the circuits for the I-paths may be summed in a corresponding adder to provide in-phase component rI(t) of the fading signal r(t). Similarly, the M output signals of the circuits for the Q-paths may be summed in a corresponding adder to provide the quadrature component rQ(t) of the fading signal r(t).
A method of generating a complex fading signal comprising the steps of:
A circuit for generating a complex fading signal comprising:
A computer-readable medium having stored thereon a plurality of instructions, the plurality of instructions including instructions which, when executed by a processor, cause the processor to implement a method for generating a complex fading signal, the method comprising the steps of:
A simulator for simulating the characteristics of signals passing through a transmission channel, the simulator including a circuit for generating a complex fading signal comprising:
Dependencies are inferred from the claim text.