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A method and apparatus for providing soft handoff in a mobile communication system. In current systems is that the members of active set are determined in accordance with comparisons of measured pilot energy with fixed thresholds. However, the value of providing a redundant communication link to a m

A method and apparatus for providing soft handoff in a mobile communication system. In current systems is that the members of active set are determined in accordance with comparisons of measured pilot energy with fixed thresholds. However, the value of providing a redundant communication link to a mobile station depends strongly on the energy of other signals being provided to the mobile station. In the present invention, the signal strengths of other base stations in communication with a mobile station are considered when determining whether adding a base to that set of base stations in communication with the remote station is of sufficient value to justify the impact on system capacity.

대표청구항 ▼

We claim: 1. A method for selecting base stations to communicate with a remote station comprising: computing a threshold value in accordance with a combination of measurements of signal energies from base stations capable of communicating with said remote station; comparing a signal energy measure

We claim: 1. A method for selecting base stations to communicate with a remote station comprising: computing a threshold value in accordance with a combination of measurements of signal energies from base stations capable of communicating with said remote station; comparing a signal energy measurement of a first base station with said threshold value; and selecting said first base station when said signal energy measurement of said first base station exceeds said threshold value; wherein said combination of signal energy measurements from base stations capable of communicating with said remote station comprises the sum of pilot energy values of pilot with greater received energy than said first base station. 2. The method of claim 1 wherein said step of computing a threshold value comprises performing a linear operation upon said combination of signal energy measurements from base stations capable of communicating with said remote station. 3. In a wireless communications system wherein a first base station transmits a first pilot signal and a first traffic signal, and a second base station transmits a second pilot signal and a second traffic signal, and a remote station receives said first pilot signal and said first traffic signal, a method for determining whether to add a third base station to an Active Set of said remote station, comprising the steps of: demodulating said first pilot signal; measuring the energy of said demodulated first pilot signal; generating a threshold in accordance with said demodulated first pilot signal energy; demodulating said second pilot signal; measuring the energy of said demodulated second pilot signal; comparing said demodulated second pilot signal energy with said threshold; adding said second base station to said Active Set when said demodulated second pilot signal energy exceeds said threshold; generating a revised threshold in accordance with a combination of said demodulated first pilot signal energy and said demodulated second pilot signal energy; demodulating a third pilot signal from said third base station; measuring the energy of said demodulated third pilot signal; comparing said demodulated third pilot signal energy with said revised threshold; and adding said third base station to said Active Set when said demodulated third pilot signal energy exceeds said revised threshold. 4. In a wireless communications system in which a plurality of base stations are in communication with a base station controller, a method for determining an Active Set of base stations to communicate with a remote station at said base station controller, comprising the steps of: receiving a signal strength measurement message indicative of the signal strengths associated with each of said plurality of base stations as measured at said remote station; selecting a first base station as a member of said Active Set of base stations; calculating a threshold value in accordance with a signal strength of said selected first base station; selecting a second base station as a member of said Active Set of base stations in accordance with said threshold value; summing the signal strengths associated with each of said two selected base stations; determining a revised threshold value in accordance with said summed signal strengths; and determining remaining members of said Active Set in accordance with said revised threshold value. 5. The method of claim 4 wherein said step of revised determining said threshold value in accordance with said summed signal strengths, comprises the steps of: multiplying said summed signal strengths by a predetermined scaling value; and adding a predetermine value to said product. 6. A method for determining the base stations to transmit to a remote station at said remote station in which a plurality of base stations comprising an Active Set of base stations transmit to said remote station and wherein a second set of base stations which are not members of said Active Set comprise a Candidate Set of base stations, said method comprising the steps of: aggregating signal energies of said Active Set of base stations; generating a threshold value in accordance with said aggregated signal energies of said base station members of said Active Set; comparing signal energy of a base station of said Candidate Set of base stations with said threshold; and adding said base station of said Candidate Set of base stations to said Active Set of base stations when said signal energy of a base station of said Candidate Set of base stations exceeds said threshold. 7. The method of claim 6 further comprising the steps of: determining membership of said Candidate Set by comparing the received signal energy from a predetermined set of base stations with a predetermined threshold. 8. The method of claim 6 further comprising the steps of: sorting members of said Candidate Set in accordance with the corresponding strength of the received signal energy. 9. The method of claim 6 further comprising the steps of: comparing the received signal strengths of a member of said Active Set against a threshold determined in accordance with the aggregate energy of the received energy of signals from base stations in the Active Set; and removing a member from said Active Set when said received signal strength of said member is less than said threshold. 10. The method of claim 8 wherein said step of removing said member from the Active set is performed at said member has remained below said threshold for a predetermined time interval. 11. The method of claim 8 further comprising the step of transmitting a pilot strength measurement message indicating for each base station in said Candidate Set and said Active Set whether to keep said member in said Active Set. 12. An apparatus for selecting base stations to communicate with a remote station comprising: means for computing a threshold value in accordance with a combination of measurements of signal energies from base stations capable of communicating with said remote station, wherein said combination of signal energy measurements from base stations capable of communicating with said remote station comprises the sum of pilot energy values of pilot with greater received energy than a first base station; means for comparing a signal energy measurement of said first base station with said threshold value; and means for selecting said first base station when said signal energy measurement of said first base station exceeds said threshold value. 13. The apparatus of claim 12 wherein said means for computing a threshold value is further for performing a linear operation upon said combination of signal energy measurements from base stations capable of communicating with said remote station. 14. In a wireless communications system wherein a first base station transmits a first pilot signal and a first traffic signal, and a second base station transmits a second pilot signal and a second traffic signal, and a remote station receives said first pilot signal and said first traffic signal, an apparatus for determining whether to add a third base station to an Active Set of said remote station, comprising: means for demodulating said first pilot signal; means for measuring the energy of said demodulated first pilot signal; means for generating a threshold in accordance with said demodulated first pilot signal energy; means for demodulating said second pilot signal; means for measuring the energy of said demodulated second pilot signal; means for comparing said demodulated second pilot signal energy with said threshold; means for adding said second base station to said Active Set when said demodulated second pilot signal energy exceeds said threshold; means for generating a revised threshold in accordance with a combination of said demodulated first pilot signal energy and said demodulated second pilot signal energy; means for demodulating a third pilot signal from said third base station; means for measuring the energy of said demodulated third pilot signal; means for comparing said demodulated third pilot signal energy with said revised threshold; and means for adding said third base station to said Active Set when said demodulated third pilot signal energy exceeds said revised threshold. 15. In a wireless communications system in which a plurality of base stations are in communication with a base station controller, an apparatus for determining an Active Set of base stations to communicate with a remote station at said base station controller, comprising: means for receiving a signal strength measurement message indicative of the signal strengths associated with each of said plurality of base stations as measured at said remote station; means for selecting a first base station as a member of said Active Set of base stations; means for calculating a threshold value in accordance with a signal strength of said selected first base station; means for selecting a second base station as a member of said Active Set of base stations in accordance with said threshold value; means for summing the signal strengths associated with each of said two selected base stations; and means for determining a revised threshold value in accordance with said summed signal strengths and; means for determining remaining members of said Active Set in accordance with said revised threshold value. 16. The apparatus of claim 15 wherein said means for determining said revised threshold value in accordance with said summed signal strengths is further for multiplying said summed signal strengths by a predetermined scaling value and adding a predetermined value to said product. 17. An apparatus for determining the base stations to transmit to a remote station at said remote station in which a plurality of base stations comprising an Active Set of base stations transmit to said remote station and wherein a second set of base stations which are not members of said Active Set comprise a Candidate Set of base stations, said apparatus comprising: means for aggregating signal energies of said Active Set of base stations; means for generating a threshold value in accordance with said aggregated signal energies of said base station members of said Active Set; means for comparing signal energy of a base station of said Candidate Set of base stations with said threshold; and means for adding said base station of said Candidate Set of base stations to said Active Set of base stations when said signal energy of a base station of said Candidate Set of base stations exceeds said threshold. 18. The apparatus of claim 17 further comprising: means for determining membership of said Candidate Set by comparing the received signal energy from a predetermined set of base stations with a predetermined threshold. 19. The apparatus of claim 17 further comprising; means for sorting members of said Candidate Set in accordance with the corresponding strength of the received signal energy. 20. The apparatus of claim 17 further comprising: means for comparing the received signal strengths of a member of said Active Set against a threshold determined in accordance with the aggregate energy of the received energy of signals from base stations in the Active Set; and means for removing a member from said Active Set when said received signal strength of said member is less than said threshold. 21. The apparatus of claim 19 wherein said means for removing said member from the Active set removes said member if said member has remained below said threshold for a predetermined time interval. 22. The apparatus of claim 19 further comprising means for transmitting a pilot strength measurement message indicating for each base station in said Candidate Set and said Active Set whether to keep said member in said Active Set. 23. A method for generating a dynamic threshold used for revising a base station set, comprising: (a) forming a combined energy value using energy values associated with members of the base station set; (b) using the combined energy value to produce the dynamic threshold; (c) comparing a received pilot energy value to the dynamic threshold to determine whether to update the base station set with a base station associated with the received pilot energy value; (d) if the received pilot energy value exceeds the dynamic threshold, then incorporating the received pilot energy value into the combined energy value, whereupon the new combined energy value is used to produce a new dynamic threshold; and (e) repeating steps (c)-(d) for each received pilot energy value. 24. An apparatus for generating a dynamic threshold used for revising a base station set, comprising: means for forming a combined energy value using energy values associated with members of the base station set; means for using the combined energy value to produce the dynamic threshold; means for comparing a received pilot energy value to the dynamic threshold to determine whether to update the base station set with a base station associated with the received pilot energy value; and means for incorporating the received pilot energy value into the combined energy value if the received pilot energy value exceeds the dynamic threshold, whereupon the new combined energy value is used to produce a new dynamic threshold. 25. An apparatus for facilitating handoff of a mobile station within a wireless communication system, comprising a processor configured to: sort a plurality of pilot energy values in a first pilot set; sum a portion of the plurality of pilot energy values in the sorted first pilot set to determine a combined pilot energy sum; determine a threshold value in accordance with the combined pilot energy sum; select a pilot energy value that is not a member of the summed portion of the plurality of pilot energy values; compare the selected pilot energy value to the threshold value; decide that the portion of the plurality of pilot energy values forming the combined pilot energy sum does not need revision if the selected pilot energy value does not exceed the threshold value; and decide that the portion of the plurality of pilot energy values forming the combined pilot energy sum needs revision if the selected pilot energy value exceeds the threshold value. 26. The apparatus of claim 25, further comprising a message generator that is controlled by the processor to transmit a message to a base station controller if the processor decides that the portion of the plurality of pilot energy values forming the combined pilot energy sum needs revision, wherein the message carries information regarding the plurality of pilot energy values. 27. The apparatus of claim 26, wherein the selected pilot energy value is selected from a Candidate Set (CS). 28. The apparatus of claim 27, wherein the first pilot set is an Active Set ( AS). 29. The apparatus of claim 28, wherein the processor is configured to sum the portion of the plurality of pilot energy values in the sorted Active Set by summing all members of the Active Set. 30. The apparatus of 29, wherein the plurality of AS pilot energy values are sorted from the weakest to the strongest. 31. The apparatus of claim 30, wherein processor is further configured to sort a plurality of Candidate Set pilot energy values from the strongest to the weakest before selecting the pilot energy value from the Candidate Set, wherein the strongest pilot energy value is selected from the Candidate Set. 32. The apparatus of claim 31, wherein the processor is further configured to: select an AS pilot energy value from the sorted AS; sum all pilot energy values of the Active Set stronger than the selected AS pilot energy value to form a combined AS pilot energy sum; determine an AS threshold value in accordance with the combined AS pilot energy sum; compare the selected AS pilot energy value to the AS threshold value; reset a drop timer if the selected AS pilot energy value exceeds the AS threshold value and store the selected AS pilot energy value and all pilot energy values of the AS stronger than the selected AS pilot energy value; and advance a drop timer for the selected AS pilot energy value if the selected AS pilot energy value does not exceed the AS threshold value. 33. The apparatus of claim 32, further comprising a message generator communicatively coupled to the processor, wherein, then the processor caused the message generator to send a pilot strength measurement message to a base station controller if the drop timer has expired. 34. The apparatus of claim 33, wherein if the drop timer has not expired, then the processor is further configured to select a next AS pilot energy value from the sorted Active Set, sum all pilot energy values of the Active Set stronger than the next selected AS pilot energy value, determine a new AS threshold value, compare the next selected AS pilot energy value to the new AS threshold value, and repeat the above steps until the drop timer is expired. 35. The apparatus of claim 34, wherein the processor is located within the mobile station. 36. The apparatus of claim 34, wherein the threshold value is determined in accordance with the following relationship: T=SOFT--SLOPE*COMBINED--PILOT+SOFT--ADD--INTERCEPT, wherein COMBINED--PILOT represents the combined pilot energy sum, and SOFT--SLOPE and SOFT --ADD--INTERCEPT are system parameters. 37. The apparatus of claim 36, wherein the AS threshold value is determined in accordance with the following relationship: T=SOFT--SLOPE*COMBINED--PILOT+SOFT--DROP--INTERCEPT, wherein COMBINED--PILOT represents the sum of all pilot energy values of the Active set stronger than the selected AS pilot energy value, and SOFT--SLOPE and SOFT--DROP--INTERCEPT are system parameters. 38. The apparatus of claim 25, wherein if the processor decides that the portion of the plurality of pilot energy values forming the combined pilot energy sum needs revision, then the processor is further configured to: include the selected pilot energy value within the combined pilot energy sum to form a revised combined pilot energy sum; determine a revised threshold value in accordance with the revised combined pilot energy sum; and select the next pilot energy value that is not a member of the summed portion of the plurality of pilot energy values, wherein the above steps repeat until a selected pilot energy value does not exceed a revised threshold value. 39. The apparatus of claim 38, wherein the summed portion of the plurality of pilot energy values is designated as an Active Set (AS). 40. The apparatus of claim 39, wherein the processor sorts the plurality of pilot energy values from the strongest pilot energy value of the first pilot set to the weakest pilot energy value of the first pilot set. 41. The apparatus of claim 40, wherein the processor is located within the mobile station. 42. The apparatus of claim 41, wherein the processor causes the message generator to send a plot strength measurement message to a base station controller if the Active Set is different from a current Active Set. 43. The apparatus of claim 40, wherein the processor is located within a base station controller. 44. The apparatus of claim 43, wherein the processor is further configured to remove from the Active Set a pilot energy value associated with a base station with a high capacity load condition. 45. The apparatus of claim 43, wherein the processor is further configured to weigh the selected pilot energy value if the selected pilot energy value is associated with a base station with a high capacity load condition. 46. The apparatus of claim 38, wherein determining the threshold value is performed in accordance to a linear operation. 47. The apparatus of claim 46, wherein the threshold value is determined in accordance with the following relationship: T=SOFT--SLOPE*COMBINED--PILOT+SOFT--INTERCEPT, wherein COMBINED--PILOT represents the combined pilot energy sum, and SOFT--SLOPE and SOFT --INTERCEPT are system parameters. 48. The apparatus of claim 47, wherein the SOFT--SLOPE and SOFT --INTERCEPT parameters are preprogrammed within the mobile station. 49. The apparatus of claim 48, wherein the SOFT--SLOPE parameter is set to 2.25 and SOFT--INTERCEPT parameter is set to 3.0. 50. The apparatus of claim 47, wherein the SOFT--SLOPE and SOFT --INTERCEPT parameters are transmitted from a base station controller to the mobile station. 51. The apparatus of claim 47, wherein the selected pilot energy value is selected from a Candidate Set (CS). 52. The apparatus of claim 51, wherein the first pilot set is an Active Set ( AS). 53. The apparatus of claim 52, wherein summing the portion of the plurality of pilot energy values in the sorted Active Set sums all members of the Active Set. 54. The apparatus of claim 53, wherein the plurality of AS pilot energy values are sorted from the weakest to the strongest. 55. The apparatus of claim 54, wherein processor is further configured to sort a plurality of Candidate Set pilot energy values from the strongest to the weakest before selecting the pilot energy value from the Candidate Set, wherein selecting occurs at the strongest pilot energy value. 56. The apparatus of claim 55, wherein the processor is further configured to: select an AS pilot energy value from the sorted AS; sum all pilot energy values of the Active Set stronger than the selected AS pilot energy value to form a combined AS pilot energy sum; determine an AS threshold value in accordance with the combined AS pilot energy sum; compare the selected AS pilot energy value to the AS threshold value; reset a drop timer if the selected AS pilot energy value exceeds the AS threshold value and store the selected AS pilot energy value and all pilot energy values of the AS stronger than the selected AS pilot energy value; and advance a drop timer for the selected AS pilot energy value if the selected AS pilot energy value does not exceed the AS threshold value. 57. The apparatus of claim 56, wherein if the drop timer has expired, then the processor removes the selected AS pilot energy value from the AS. 58. The apparatus of claim 57, wherein if the drop timer has not expired, then the processor is further configured to: select a next AS pilot energy value from the sorted Active Set; sum all pilot energy values of the Active Set stronger than the next selected AS pilot energy value; determine a new AS threshold value; compare the next selected AS pilot energy value to the new AS threshold value; and repeat the above steps until the drop timer is expired. 59. The apparatus of claim 58, wherein the processor is located within the mobile station. 60. The apparatus of claim 59, further comprising a message generator that is controlled by the processor to transmit a message to a base station controller if the processor decides the Active Set is different from a current Active Set. 61. The apparatus of claim 59, further comprising a message generator that is controlled by the processor to transmit a message to a base station controller if the processor decides the Candidate Set is different from a current Candidate Set. 62. The apparatus of claim 58, wherein the processor is located within a base station controller. 63. The apparatus of claim 62, wherein the processor is further configured to remove from the Active Set a pilot energy value associated with a base station with a high capacity load condition. 64. The apparatus of claim 62, wherein the processor is further configured to weigh the selected AS pilot energy value if the selected AS pilot energy value is associated with a base station with a high capacity load condition. 65. The apparatus of claim 38, wherein determining the threshold value is performed in accordance to a linear operation. 66. The apparatus of claim 65, wherein the threshold value is determined in accordance with the following relationship: T=SOFT--SLOPE*COMBINED--PILOT+SOFT--INTERCEPT, wherein COMBINED--PILOT represents the combined pilot energy sum, and SOFT--SLOPE and SOFT --INTERCEPT are system parameters. 67. The apparatus of claim 66, wherein the SOFT--SLOPE and SOFT --INTERCEPT parameters are preprogrammed within the mobile station. 68. The apparatus of claim 67, wherein the SOFT--SLOPE parameter is set to 2.25 and SOFT--INTERCEPT parameter is set to 3.0. 69. The apparatus of claim 66, wherein the SOFT--SLOPE and SOFT --INTERCEPT parameters are transmitted from a base station controller to the mobile station. 70. The apparatus of claim 66, wherein the AS threshold value is determined in accordance with the following relationship: T=SOFT--SLOPE*COMBINED--PILOT+SOFT--INTERCEPT, wherein COMBINED--PILOT represents the sum of all pilot energy values of the Active set stronger than the selected AS pilot energy value, and SOFT--SLOPE and SOFT--INTERCEPT are system parameters. 71. An apparatus for shortening a search through adjacent pilot sets that are used for facilitating handoff of a mobile station within a wireless communication system, comprising: a processor configured to execute a set of instructions for: sorting a first pilot set from a stronger first pilot energy value to a weakest first pilot energy value; selecting a first pilot energy value from the sorted first pilot set; comparing the selected first pilot energy value to a first threshold value; if the selected first pilot energy value exceeds the first threshold value, then reallocating the selected first pilot energy value to a second pilot set and selecting the next first pilot energy value from the sorted first pilot set, wherein the above steps repeat until a selected first pilot energy value does not exceed the first threshold value; if the selected first pilot energy value does not exceed the first threshold value, then: sorting a second pilot set from a weakest second pilot energy value to a strongest second pilot energy value; selecting a second pilot energy value from the sorted second pilot set; and comparing the selected second pilot energy value to a second threshold value. 72. The apparatus of claim 71, wherein the set of instructions is further for: if the selected second pilot energy value exceeds the second threshold value, then resetting a drop timer and finishing the search; and if the selected second pilot energy value does not exceed the second threshold value, then advancing a drop timer, selecting a next second pilot energy value from the sorted second pilot set, and comparing the next selected second pilot energy to the second threshold value, wherein the above steps repeat until the drop timer expires. 73. The apparatus of claim 72, wherein the set of instructions is further for: if the drop time expires, then removing the selected second pilot energy value from the second pilot set. 74. The apparatus of claim 73, wherein the first pilot set is a Neighbor Set. 75. The apparatus of claim 74, wherein the second pilot set is a Candidate Set. 76. The apparatus of claim 72, wherein the processor is located within the mobile station. 77. The apparatus of claim 72, wherein the processor is located within a base station controller. 78. An apparatus for facilitating handoff of a mobile station within a wireless communication system by timely updating pilot energies from base stations, comprising: a processor for summing a portion of the plurality of pilot energy values in a first pilot set to determine a combined pilot energy sum, and for determining a threshold value in accordance with the combined pilot energy sum, wherein the threshold value is updated to incorporate pilot energy values that exceed the threshold value and the first pilot set is revised to incorporate base stations associated with the pilot energy values that exceed the threshold value; and a generator for generating a message carrying first pilot set information. 79. The apparatus of claim 78, wherein the processor is further for sorting a plurality of pilot energy values in the first pilot set. 80. The apparatus of claim 78, wherein the processor is further for: selecting a pilot energy value that is not a member of the summed portion of the plurality of pilot energy values; and comparing the selected pilot energy value to the threshold value to decide whether to revise the first pilot set. 81. The apparatus of claim 80, wherein if the compared pilot energy value does not exceed the threshold value, then deciding that the portion of the plurality of pilot energy values forming the combined pilot energy sum need not include the compared pilot energy value so that the first pilot set need not be revised. 82. The apparatus of claim 80, wherein if the compared pilot energy value exceeds the threshold value, then deciding that the portion of the plurality of pilot energy values forming the combined pilot energy sum needs to include the compared pilot energy value so that the first pilot set needs to be revised. 83. In a wireless communication system wherein a remote station is in communication with a plurality of base stations, a method for selecting an additional base station for communication with the remote station comprising: sorting a plurality of signal energies according to signal strength, wherein each of the plurality of signal energies correspond with one of the plurality of base stations; computing a threshold value from a subset of the plurality of signal energies, wherein the subset of the plurality of signal energies is determined by the step of sorting the plurality of signal energies; comparing a signal energy measurement of the additional base station with said threshold value; and selecting the additional base station when the signal energy measurement of the additional base station exceeds the threshold value. 84. The method of claim 83 wherein computing a threshold value comprises performing a linear operation upon the plurality of signal energies. 85. The method of claim 84 wherein said linear operation comprises: multiplying said plurality of signal energies by a first variable; and summing a second variable with the product of said multiplication. 86. The method of claim 85 wherein said first variable has a value of 2. 25. 87. The method of claim 85 wherein said second variable has a value of 3. 0. 88. The method of claim 83, the method further comprising transmitting a message indicative of the signal energy measurement of the additional base station from said remote station. 89. The method of claim 83, the method further comprising removing a weak base station from the plurality of base stations when the signal energy measurement of the weak base station is below said threshold value. 90. In a wireless communication system wherein a remote station is in communication with at least one base station, an apparatus for maintaining communications between the remote station and the at least one base station in accordance with signal strength, comprising: means for receiving pilot signals from base stations; means for: sorting a plurality of signal energies according to signal strength, wherein each of the plurality of signal energies correspond with one of the plurality of base stations; computing a threshold value from a subset of the plurality of signal energies, wherein the subset of the plurality of signal energies is determined by the step of sorting the plurality of signal energies; comparing a signal energy measurement of the additional base station with said threshold value; and selecting the additional base station when the signal energy measurement of the additional base station exceeds the threshold value, wherein the processor means is communicatively connected to the receiver means. 91. A method for facilitating handoff of a mobile station within a wireless communication system, comprising: sorting a plurality of pilot energy values in a first pilot set; summing a portion of the plurality of pilot energy values in the sorted first pilot set to determine a combined pilot energy sum; determining a threshold value in accordance with the combined pilot energy sum; selecting a pilot energy value that is not a member of the summed portion of the plurality of pilot energy values; comparing the selected pilot energy value to the threshold value; deciding that the portion of the plurality of pilot energy values forming the combined pilot energy sum does not need revision if the selected pilot energy value does not exceed the threshold value; and deciding that the portion of the plurality of pilot energy values forming the combined pilot energy sum needs revision if the selected pilot energy value exceeds the threshold value. 92. The method of claim 91, wherein deciding that the portion of the plurality of pilot energy values forming the combined pilot energy sum needs revision comprises: including the selected pilot energy value within the combined pilot energy sum to form a revised combined pilot energy sum; determining a revised threshold value in accordance with the revised combined pilot energy sum; and selecting the next pilot energy value that is not a member of the summed portion of the plurality of pilot energy values, wherein the above steps repeat until a selected pilot energy value does not exceed a revised threshold value. 93. A method for shortening a search through adjacent pilot sets that are used for facilitating handoff of a mobile station within a wireless communication system, comprising: sorting a first pilot set from a strongest first pilot energy value to a weakest first pilot energy value; selecting a first pilot energy value from the sorted first pilot set; comparing the selected first pilot energy value to a first threshold value; and if the selected first pilot energy value exceeds the first threshold value, then reallocating the selected first pilot energy value to a second pilot set and selecting the next first pilot energy value from the sorted first pilot set, wherein the above steps repeat until a selected first pilot energy value does not exceed the first threshold value; or if the selected first pilot energy value does not exceed the first threshold value, then: sorting a second pilot set from a weakest second pilot energy value to a strongest second pilot energy value; selecting a second pilot energy value from the sorted second pilot set; and comparing the selected second pilot energy value to a second threshold value. 94. The method of claim 93, further comprising: if the selected second pilot energy value exceeds the second threshold value, then resetting a drop timer and finishing the search; and if the selected second pilot energy value does not exceed the second threshold value, then advancing a drop timer, selecting a next second pilot energy value from the sorted second pilot set, and comparing the next selected second pilot energy to the second threshold value, wherein the above steps repeat until the drop timer expires.