US5987076A — Coherent signal processing for CDMA communication…

Claim 1

Independent Claim 122 words

A method for receive processing a set of multipath signals comprising the steps of: a) calculating a set of phase references corresponding to the set of multipath signals; b) projecting said set of multipath signals using said set of phase references yielding a set of projected multipath signals; and c) combining said set of projected multipath signals; wherein step a) comprises the steps of: a.1) determining a Walsh symbol with the highest likelihood to have been transmitted using said set of multipath signals; a.2) selecting said Walsh symbol from an in-phase portion of each multipath signal from said set of multipath signals; and a.3) selecting said Walsh symbol from a quadrature-phase portion of each multipath signal from said set of multipath signals.

Claim 2

Independent Claim 122 words

A method for receive processing a set of multipath signals comprising the steps of: a) calculating a set of phase references corresponding to the set of multipath signals; b) projecting said set of multipath signals using said set of phase references yielding a set of projected multipath signals; and c) combining said set of projected multipath signals; wherein step a) comprises the steps of: a.1) determining a Walsh symbol with the highest likelihood to have been transmitted using said set of multipath signals; a.2) selecting said Walsh symbol from an in-phase portion of each multipath signal from said set of multipath signals; and a.3) selecting said Walsh symbol from a quadrature-phase portion of each multipath signal from said set of multipath signals.

Claim 3

Dependent Claim 72 words

The method as set forth in claim 1 wherein step a.1) is comprised of the steps of: generating a set of Walsh symbol correlation vectors corresponding to the set of multipath signals; generating a set of correlation energy vectors corresponding to said set of Walsh symbol correlation vectors; summing said set of correlation energy vectors yielding a summed correlation energy vector; and performing a hard decision using said summed correlation energy vector.

Claim 4

Dependent Claim 61 words

The method as set forth in claim 2 wherein step c) yields a coherent correlation vector and further comprises the step of: selecting said coherent correlation vector if a rate of phase variation is less than a second threshold and selecting said summed correlation energy vector for further processing if said rate of phase variation is greater than second second threshold.

Claim 5

Dependent Claim 25 words

The method as set forth in claim 3 wherein said second threshold is equal to or greater than approximately 52 degrees per Walsh symbol period.

Claim 6

Independent Claim 121 words

A method for receive processing a set of multipath signals comprising the steps of: a) calculating a set of phase references corresponding to the set of multipath signals; b) projecting said set of multipath signals using said set of phase references yielding a set of projected multipath signals; and c) combining said set of projected multipath signals; wherein step a) is performed via the steps of: a.1) generating a set of in-phase references corresponding to the set of multipath signals; and a.2) generating a set of quadrature-phase reference corresponding to the set of multipath signals; wherein step a.1) comprises the step of: summing a set of in-phase Walsh symbol correlation values over less than or equal to a power control group.

Claim 7

Independent Claim 121 words

A method for receive processing a set of multipath signals comprising the steps of: a) calculating a set of phase references corresponding to the set of multipath signals; b) projecting said set of multipath signals using said set of phase references yielding a set of projected multipath signals; and c) combining said set of projected multipath signals; wherein step a) is performed via the steps of: a.1) generating a set of in-phase references corresponding to the set of multipath signals; and a.2) generating a set of quadrature-phase reference corresponding to the set of multipath signals; wherein step a.1) comprises the step of: summing a set of in-phase Walsh symbol correlation values over less than or equal to a power control group.

Claim 8

Dependent Claim 36 words

The method as set forth in claim 5 wherein step a.2) is comprised of the steps of: summing a set of quadrature-phase Walsh symbol correlation values over less than or equal to said power control group.

Claim 9

Independent Claim 163 words

A method for receive processing a set of multipath signals comprising the steps of: a) calculating a set of phase references corresponding to the set of multipath signals; b) projecting said set of multipath signals using said set of phase references yielding a set of projected multipath signals; and c) combining said set of projected multipath signals; wherein step a) is performed via the steps of: a.1) generating a set of in-phase references corresponding to the set of multipath signals; and a.2) generating a set of quadrature-phase reference corresponding to the set of multipath signals; wherein step a.1) comprises the steps of: summing a set of Walsh symbol correlation values over less than or equal to five Walsh symbol periods when a rate of phase variation is less than a first threshold, and summing said set of Walsh symbol correlation values over less than or equal to three Walsh symbol periods when said rate of phase variation is greater than said first threshold.

Claim 10

Independent Claim 163 words

A method for receive processing a set of multipath signals comprising the steps of: a) calculating a set of phase references corresponding to the set of multipath signals; b) projecting said set of multipath signals using said set of phase references yielding a set of projected multipath signals; and c) combining said set of projected multipath signals; wherein step a) is performed via the steps of: a.1) generating a set of in-phase references corresponding to the set of multipath signals; and a.2) generating a set of quadrature-phase reference corresponding to the set of multipath signals; wherein step a.1) comprises the steps of: summing a set of Walsh symbol correlation values over less than or equal to five Walsh symbol periods when a rate of phase variation is less than a first threshold, and summing said set of Walsh symbol correlation values over less than or equal to three Walsh symbol periods when said rate of phase variation is greater than said first threshold.

Claim 11

Dependent Claim 25 words

The method as set forth in claim 7 wherein said first threshold is greater than or equal to approximately 30 degrees per Walsh symbol period.

Claim 12

Independent Claim 86 words

A system for processing a set of multipath signals comprising: radio frequency signal processing system for generating digitized signals by processing the set of multipath signals; demodulation system for generating demodulated data by demodulating said digitized signals; delay circuit for generating delayed demodulated data by delaying said demodulated data; reference circuit for generating references using said demodulated data; projection system for generating projected data projecting by projecting said delayed demodulated data using said references; and combiner for generating a coherent vector by combining said projected data.

Claim 13

Independent Claim 86 words

A system for processing a set of multipath signals comprising: radio frequency signal processing system for generating digitized signals by processing the set of multipath signals; demodulation system for generating demodulated data by demodulating said digitized signals; delay circuit for generating delayed demodulated data by delaying said demodulated data; reference circuit for generating references using said demodulated data; projection system for generating projected data projecting by projecting said delayed demodulated data using said references; and combiner for generating a coherent vector by combining said projected data.

Claim 14

Dependent Claim 21 words

The system as set forth in claim 9 wherein said references are comprised of an in-phase references and a quadrature-phase references.

Claim 15

Dependent Claim 35 words

The system as set forth in claim 10 wherein said reference circuit generates said in-phase references and said quadrature-phase references by summing said demodulated data over less than or equal to a power control group.

Claim 16

Dependent Claim 130 words

A demodulation system comprising: plurality of finger processing means for generating a corresponding plurality of demodulated fingers; data identifier means for identifying transmitted data using said plurality of demodulated fingers; reference generation means for generating a plurality of in-phase references based on an in-phase portion of each of said plurality of demodulated fingers, and for generating a plurality of quadrature-phase references based on a quadrature-phase portion of each of said plurality of demodulated fingers; projection means for generating projected data by projecting said in-phase portion of each of said plurality of demodulated fingers and said quadrature-phase portion of each of said plurality of demodulated fingers using said plurality of in-phase references and said plurality of quadrature-phase references; and combiner means for generating coherently combined data by combining said projected data.

Claim 17

Dependent Claim 130 words

A demodulation system comprising: plurality of finger processing means for generating a corresponding plurality of demodulated fingers; data identifier means for identifying transmitted data using said plurality of demodulated fingers; reference generation means for generating a plurality of in-phase references based on an in-phase portion of each of said plurality of demodulated fingers, and for generating a plurality of quadrature-phase references based on a quadrature-phase portion of each of said plurality of demodulated fingers; projection means for generating projected data by projecting said in-phase portion of each of said plurality of demodulated fingers and said quadrature-phase portion of each of said plurality of demodulated fingers using said plurality of in-phase references and said plurality of quadrature-phase references; and combiner means for generating coherently combined data by combining said projected data.

Claim 18

Dependent Claim 42 words

The demodulation system of claim 12 further comprising: non-coherent combiner means for generating a non-coherently combined correlation vector by non-coherently combining said plurality of demodulated fingers; and hard decision means for generating a transmitted data identifier using said non-coherently combined correlation vector.

Claim 19

Dependent Claim 49 words

The demodulation system of claim 13 further comprising: process select means for generating a process select indicator; and vector select means for selecting said non-coherently combined correlation vector if indicated by said process select indicator, and for selecting said coherently combined data if indicated by said process select indicator.

Claim 20

Dependent Claim 28 words

The demodulation system of claim 13 wherein said reference generation means is further for averaging said transmitted data over less than of equal to six Walsh symbol periods.

Claim 21

Dependent Claim 84 words

The demodulation system of claim 15 further comprising: reference generation method select means for generating a reference generation method select value indicating if a rate of phase variation is above a first threshold, and said reference generation means is further for averaging said transmitted data over less than or equal to three Walsh symbol periods if said reference generation method select value is positive, and over less than or equal to five Walsh symbol periods if said reference generation method select value is negative.

Claim 22

Dependent Claim 18 words

The demodulation system of claim 16 wherein said first threshold is approximately 30 degrees per Walsh symbol period.

Claim 23

Dependent Claim 53 words

The demodulation system of claim 14 wherein said process select indicator indicates set coherently combined data should be selected if a rate of phase change is less than a second threshold, and indicates said non-coherently combined correlation vector should be selected if said rate of phase change is greater than said second threshold.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	2002-11-15	2003-05-17	2003-11-16	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	2006-11-15	2007-05-17	2007-11-16	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2010-11-15	2011-05-17	2011-11-16	$7700.00	Window Closed / Lapsed

Coherent signal processing for CDMA communication system

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