# US 7,613,230 B2 · Method of processing a signal by a radio receiver and radio receiver for the implementation of the method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,613,230 B2 - Document ID: US7613230B2 - Status: Granted - Kind: B2 - Application number: 10/807,664 - Filed: 2004-03-24 - Published: 2004-12-02 - Granted: 2009-11-03 - Earliest claimed: 2003-03-31 - Assignees: Alcatel Lucent - Inventors: Alexandre Jard; Moussa Abdi; Hassan El Nahas El Homsi; Jean-Marc Corbel - Web page: https://patentgrep.com/patent/US7613230B2 ## CPC - H04B 1/7113: Determination of path profile - H04B 1/7117: Selection, re-selection, allocation or re-allocation of paths to fingers, e.g. timing offset control of allocated fingers - H04B: TRANSMISSION ## Abstract In a spread spectrum digital radio communication receiver, a propagation profile of a propagation channel between a sender and the receiver, including at least one propagation path associated with a reception energy, is determined, data relating to an energy distribution in the propagation profile are measured, and information symbols carried by a signal received originating from the sender over the propagation channel are estimated, by applying to the signal a processing taking into account a predetermined maximum number of propagation paths, the propagation paths taken into account being chosen according to a criterion selected from several criteria as a function of the measured data relating to the energy distribution in the propagation profile. ## Claims ### Claim 1 A method of signal processing for a spread spectrum digital radio communication receiver, comprising the following steps: determining a propagation profile of a propagation channel between sending means and the receiver, including at least one propagation path associated with a reception energy; measuring data relating to an energy distribution in the propagation profile; estimating information symbols carried by a signal originating from said sending means and received over the propagation channel, by applying to said signal a processing taking into account a predetermined maximum number of propagation paths, said propagation paths taken into account being chosen according to a criterion selected from several criteria, in which said criterion is selected as a function of the measured data relating to the energy distribution in the propagation profile. ### Claim 2 (depends on 1) A method according to claim 1, in which the step of determining a propagation profile of a propagation channel between the sending means and the receiver comprises a processing applied to the signal received identifying, on the basis of an analysis of an impulse response of the propagation channel between the sending means and the receiver, a number of propagation paths detected and respective reception energies for these paths. ### Claim 3 (depends on 1) A method according to claim 1, in which said propagation paths taken into account are chosen according to a criterion selected from a set comprising a first criterion according to which the predetermined maximum number of propagation paths of greatest energy on average are taken into account, and a second criterion according to which the predetermined maximum number of propagation paths of largest instantaneous energy are taken into account. ### Claim 4 (depends on 1) A method according to claim 1, in which the measured data relating to the energy distribution in the propagation profile comprise a measurement of energy dispersion for the propagation paths detected. ### Claim 5 (depends on 4) A method according to claim 4, in which the selection of said criterion as a function of the measured data relating to the energy distribution in the propagation profile comprises a comparison of said measurement of energy dispersion for the propagation paths detected with a threshold. ### Claim 6 (depends on 5) A method according to claim 5, in which said threshold is obtained in relation to a prior choice of a gap in performance between two strategies for choosing propagation paths taken into account in said processing according to respective criteria. ### Claim 7 (depends on 6) A method according to claim 6, in which the obtaining of the threshold is done on the basis of correspondences between an energy dispersion in a propagation profile and a gap in performance between two strategies for choosing propagation paths according to respective criteria, the correspondences being preestablished under various radio conditions. ### Claim 8 (depends on 4) A method according to claim 4, in which the measurement of energy dispersion for the propagation paths detected comprises an estimation of a mean energy gap between the propagation paths detected. ### Claim 9 (depends on 8) A method according to claim 8, in which the mean energy gap between the propagation paths detected is estimated in the least squares sense. ### Claim 10 (depends on 8) A method according to claim 8, in which the mean energy gap between the propagation paths detected is estimated according to an arithmetic mean of ratios between the energies of consecutive paths from among the propagation paths detected. ### Claim 11 A spread spectrum digital radio communication receiver comprising means for determining a propagation profile of a propagation channel between sending means and the receiver, including at least one propagation path associated with a reception energy, means for measuring data relating to an energy distribution in the propagation profile, means for choosing a predetermined maximum number of propagation paths according to a criterion for choosing, means for estimating information symbols carried by a signal originating from said sending means and received over the propagation channel, by applying to said signal a processing taking into account the paths chosen, said spread spectrum digital radio communication receiver furthermore comprising means for selecting said criterion for choosing from several criteria, said criterion for choosing being selected as a function of the data measured by the means relating to the energy distribution in the propagation profile. ### Claim 12 (depends on 11) A receiver according to claim 11, in which the means for determining a propagation profile of a propagation channel between sending means and the receiver comprise means for applying to the signal received a processing identifying, on the basis of an analysis of an impulse response of the propagation channel between the sending means and the receiver, a number of propagation paths detected and respective reception energies for these paths. ### Claim 13 (depends on 11) A receiver according to claim 11, in which the means for selecting a criterion for choosing from several criteria as a function of the measured data relating to the energy distribution in the propagation profile are designed to select a criterion for choosing from a set comprising a first criterion according to which the predetermined maximum number of propagation paths of greatest energy on average are taken into account, and a second criterion according to which the predetermined maximum number of propagation paths of largest instantaneous energy are taken into account. ### Claim 14 (depends on 11) A receiver according to claim 11, in which the means for measuring data relating to an energy distribution in the propagation profile comprise means for measuring an energy dispersion for the propagation paths detected. ### Claim 15 (depends on 14) A receiver according to claim 14, in which the means for selecting a criterion for choosing from several criteria as a function of the measured data relating to the energy distribution in the propagation profile are designed to make a selection which comprises a comparison of said measurement of energy dispersion for the propagation paths detected with a threshold. ### Claim 16 (depends on 15) A receiver according to claim 15, in which the means for selecting a criterion for choosing from several criteria as a function of the measured data relating to the energy distribution in the propagation profile are designed to obtain said threshold in relation to a prior choice of a gap in performance between two strategies for choosing the propagation paths. ### Claim 17 (depends on 16) A receiver according to claim 16, in which the means for selecting a criterion for choosing from several criteria as a function of the measured data relating to the energy distribution in the propagation profile comprise means for storing correspondences between an energy dispersion in a propagation profile and a gap in performance between two strategies for choosing propagation paths according to respective criteria, said correspondences being preestablished under various radio conditions. ### Claim 18 (depends on 17) A receiver according to claim 17, in which the means for selecting a criterion for choosing from several criteria as a function of the measured data relating to the energy distribution in the propagation profile are designed to obtain the threshold on the basis of the correspondences stored in the means for storing correspondences between an energy dispersion in a propagation profile and a gap in performance between two strategies for choosing the propagation paths according to respective criteria. ### Claim 19 (depends on 14) A receiver according to claim 14, in which the means for measuring an energy dispersion for the propagation paths detected are designed to estimate a mean energy gap between the propagation paths detected. ### Claim 20 (depends on 19) A receiver according to claim 19, in which the means for measuring an energy dispersion for the propagation paths detected are designed to estimate a mean energy gap between the propagation paths detected in the least squares sense. ### Claim 21 (depends on 19) A receiver according to claim 19, in which the means for measuring an energy dispersion for the propagation paths detected are designed to estimate a mean energy gap between the propagation paths detected according to an arithmetic mean of ratios between the energies of consecutive paths from among the propagation paths detected. ### Claim 22 A computer program stored on a tangible medium, and comprising instructions for the implementation, during the execution of said program by a processor, of the followings steps: determining a propagation profile of a propagation channel between sending means and the receiver, including at least one propagation path associated with a reception energy; measuring data relating to an energy distribution in the propagation profile; estimating information symbols carried by a signal originating from said sending means and received over the propagation channel, by applying to the said signal a processing taking into account a predetermined maximum number of propagation paths, the said propagation paths taken into account being chosen according to a criterion selected from several criteria, in which said criterion is selected as a function of the measured data relating to the energy distribution in the propagation profile. ### Claim 23 (depends on 22) A computer program according to claim 22, in which the step of determining a propagation profile of a propagation channel between sending means and the receiver comprises a processing applied to the signal received identifying, on the basis of an analysis of an impulse response of the propagation channel between the sending means and the receiver, a number of propagation paths detected and respective reception energies for these paths. ### Claim 24 (depends on 22) A computer program according to claim 22, in which said propagation paths taken into account are chosen according to a criterion selected from a set comprising a first criterion according to which the predetermined maximum number of propagation paths of greatest energy on average are taken into account, and a second criterion according to which the predetermined maximum number of propagation paths of largest instantaneous energy are taken into account. ### Claim 25 (depends on 22) A computer program according to claim 22, in which the measured data relating to the energy distribution in the propagation profile comprise a measurement of energy dispersion for the propagation paths detected. ### Claim 26 (depends on 25) A computer program according to claim 25, in which the selection of said criterion as a function of the measured data relating to the energy distribution in the propagation profile comprises a comparison of said measurement of energy dispersion for the propagation paths detected with a threshold. ### Claim 27 (depends on 26) A computer program according to claim 26, in which said threshold is obtained in relation to a prior choice of a gap in performance between two strategies for choosing propagation paths taken into account in said processing according to respective criteria. ### Claim 28 (depends on 27) A computer program according to claim 27, in which the obtaining of the threshold is done on the basis of correspondences between an energy dispersion in a propagation profile and a gap in performance between two strategies for choosing propagation paths according to respective criteria, the correspondences being preestablished under various radio conditions. ### Claim 29 (depends on 25) A computer program according to claim 25, in which the measurement of energy dispersion for the propagation paths detected comprises an estimation of a mean energy gap between the propagation paths detected. ### Claim 30 (depends on 29) A computer program according to claim 29, in which the mean energy gap between the propagation paths detected is estimated in the least squares sense. ### Claim 31 (depends on 29) A computer program according to claim 29, in which the mean energy gap between the propagation paths detected is estimated according to an arithmetic mean of ratios between the energies of consecutive paths from among the propagation paths detected. ### Claim 32 A computer medium in which is recorded a program comprising instructions for the implementation of the followings steps, when executed by a processor: determining a propagation profile of a propagation channel between sending means and the receiver, including at least one propagation path associated with a reception energy; measuring data relating to an energy distribution in the propagation profile; estimating information symbols carried by a signal received originating from said sending means and received over the propagation channel, by applying to the said signal a processing taking into account a predetermined maximum number of propagation paths, the said propagation paths taken into account being chosen according to a criterion selected from several criteria, said criterion being selected as a function of the measured data relating to the energy distribution in the propagation profile.