Method and apparatus for measurement directed hard handoff in a CDMA system

Claim 2

In a communications network in which a network user communicates through a remote unit with another user via at least one base station, said network including first and second mobile switching centers for respectively controlling communications through a first set of base stations including a first base station and through a second set of base stations including a second base station, a method for directing communications between said remote unit and said first and second base stations comprising the steps of: measuring at said first base station a round trip delay of an active communication signal between said first base station and said remote unit; measuring at said remote unit a first phase offset of a pilot signal received from a first candidate base station; reporting by said remote unit to said first mobile switching center via said first base station said first phase offset; calculating at said first mobile switching center a candidate round trip delay between said remote unit and said first candidate base station based on said first phase offset and said round trip delay of said active communication signal; entering a measurement directed hard handoff state by an active communication control unit in said first mobile switching center wherein said measurement directed hard handoff state enables said step of calculating; and accessing by said active communication control unit a measurement directed hard handoff table to determine, based on said round trip delay corresponding to said active communication signal and said candidate round trip delay, whether the location of said remote unit corresponds to an area where a handoff is desirable; wherein said measurement directed hard handoff table comprises an entry designating a type of action that should be taken based on a location of said remote unit.

Claim 3

The method of claim 1 further comprising the step of transmitting from each of said first set of base stations a common pilot sequence wherein each of said first set of base stations transmits said common pilot sequence at an identifying channel offset.

Claim 4

The method of claim 2 wherein said step of calculating said candidate round trip delay is computed as RTD.sub.can1 =RTD.sub.ref +2*(PilotPhase.sub.can1 -ChannelOffset.sub.can1 *PilotInc) where: RTD can1 =said candidate round trip delay; RTD ref =said round trip delay of said active communication signal; PilotPhase can1 =said first phase offset; and ChannelOffset can1 * PilotInc=an identifying channel offset corresponding to said first candidate base station.

Claim 5

The method of claim 1 wherein said first candidate base station is controlled by said first mobile switching center.

Claim 6

The method of claim 1 wherein said first candidate base station is controlled by said second mobile switching center.

Claim 7

The method of claim 1 wherein said first candidate base station is controlled by said second mobile switching center and said pilot signal from said first candidate base station is generated by a pilot beacon unit.

Claim 8

The method of claim 3 wherein said first candidate base station is controlled by said second mobile switching center and said pilot signal from said first candidate base station is generated by a pilot beacon unit.

Claim 9

The method of claim 1 further comprising the steps of: storing at said remote unit a list of active base stations comprising an entry corresponding to each base station with which active communication is established; storing at said remote unit a list of candidate base stations comprising an entry corresponding to each base station through which active communication may be possible but is not established and said list of candidate base stations has an entry for said first candidate base station; and storing at said remote unit a list of neighbor base stations from which said list of candidate base stations is chosen.

Claim 10

The method of claim 1 wherein said active communication control unit is a selector.

Claim 11

The method of claim 1 wherein a first border set of base stations controlled by said first mobile switching center each have a coverage area that abuts a coverage area corresponding to a base station controlled by said second mobile switching center further comprising the steps of: storing at said remote unit a list of active base stations comprising an entry corresponding to each base station with which active communication is established; and executing the step of entering said measurement directed hard handoff state only when said list of active base stations comprises an entry corresponding to one of said first border set of base stations.

Claim 12

The method of claim 1 wherein a first border set of base stations controlled by said first mobile switching center each have a coverage area that abuts a coverage area corresponding to a base station controlled by said second mobile switching center further comprising the steps of: storing at said remote unit a list of active base stations comprising an entry corresponding to each base station with which active communication is established; and executing the step of entering said measurement directed hard handoff state only when each entry on said list of active base stations corresponds to said first border set of base stations.

Claim 13

The method of claim 1 wherein a first border set of base stations controlled by said first mobile switching center each have a coverage area that abuts a coverage area corresponding to a base station controlled by said second mobile switching center further comprising the steps of: wherein said remote unit stores a list of active base stations comprising an entry corresponding to each base station with which active communication is established; and executing the step of entering said measurement directed hard handoff state only when said list of active base stations comprises a single entry and said single entry corresponds to one of said first border set of base stations.

Claim 14

The method of claim 1 further comprising the step of accessing by said active communication control unit a measurement directed hard handoff table to determine a location of said remote unit based on said round trip delay corresponding to said active communication signal and said candidate round trip delay.

Claim 15

The method of claim 1 wherein said type of action that should be taken is a handoff from said first base station which is communicating with said remote unit using code division multiple access (CDMA) to said second base station operating using an alternative modulation technology.

Claim 16

The method of claim 14 wherein said alternative modulation technology is frequency modulation (FM.).

Claim 17

The method of claim 14 wherein said alternative modulation technology is time division multiple access (TDMA.).

Claim 18

The method of claim 1 wherein said type of action that should be taken is a handoff from said first base station which is communicating at a first frequency with said remote unit using CDMA to said second base station communicating at a second frequency using CDMA.

Claim 19

The method of claim 1 wherein said type of action that should be taken is a handoff from said first base station which is communicating at a first frequency with said remote unit using CDMA to said first base station communicating with said remote unit using an alternative modulation technology.

Claim 20

The method of claim 1 wherein said type of action that should be taken is a handoff from said first base station which is communicating at a first frequency with said remote unit using CDMA to said first base station communicating at a second frequency using CDMA.

Claim 21

The method of claim 1 wherein said active communication signal is comprised of a set of multipath signals each having a different delay and wherein said round trip delay of said active communication signal is the round trip delay corresponding to the earliest arriving multipath signal of said set of multipath signals.

Claim 22

The method of claim 1 wherein said step of accessing is executed when said round trip delay of said active communication signal changes by a predetermined amount.

Claim 23

The method of claim 1 wherein said step of accessing is executed whenever said step of reporting by said remote unit is repeated.

Claim 24

The method of claim 1 wherein said active communication signal is a spread spectrum signal which is spread by a pseudorandom noise (PN) sequence and wherein said round trip delay of said active communication signal is measured in PN chips.

Claim 25

The method of claim 3 wherein said active communication signal is a spread spectrum signal which is spread by a pseudorandom noise (PN) sequence and wherein said round trip delay of said active communication signal is measured in PN chips, said identifying channel offset is measured in PN chips, and said candidate round trip delay is measured in PN chips.

Claim 26

In a communications network in which a network user communicates through a remote unit with another user via at least one base station, said network including first and second mobile switching centers for respectively controlling communications through a first set of base stations including a first base station and through a second set of base stations including a second base station, a method for directing communications between said remote unit and said first and second base stations comprising the steps of: measuring at said first base station a round trip delay of an active communication signal between said first base station and said remote unit; entering a measurement directed hard handoff state by an active communication control unit located in said first mobile switching center; and accessing by said active communication control unit a measurement directed hard handoff table to determine based on said round trip delay corresponding to said active communication signal whether a location of said remote unit corresponds to an area where a handoff is desirable; wherein said measurement directed hard handoff table comprises an entry specifying a type of action that should be taken based on said location of said remote unit.

Claim 27

In a communications network in which a network user communicates through a remote unit with another user via at least one base station, said network including first and second mobile switching centers for respectively controlling communications through a first set of base stations including a first base station and through a second set of base stations including a second base station, a method for directing communications between said remote unit and said first and second base stations comprising the steps of: measuring at said first base station a round trip delay of an active communication signal between said first base station and said remote unit; entering a measurement directed hard handoff state by an active communication control unit located in said first mobile switching center; and accessing by said active communication control unit a measurement directed hard handoff table to determine based on said round trip delay corresponding to said active communication signal whether a location of said remote unit corresponds to an area where a handoff is desirable; wherein said measurement directed hard handoff table comprises an entry specifying a type of action that should be taken based on said location of said remote unit.

Claim 28

The method of claim 25 further comprising the step of transmitting from each of said first set of base stations a common pilot sequence wherein each of said first set of base stations transmits said common pilot sequence at an identifying channel offset.

Claim 29

The method of claim 25 wherein said active communication control unit is a selector.

Claim 30

The method of claim 25 wherein said type of action that should be taken is a handoff from said first base station which is communicating with said remote unit using code division multiple access (CDMA) to said second base station operating using an alternative modulation technology.

Claim 31

The method of claim 24 wherein said alternative modulation technology is frequency modulation (FM.).

Claim 32

The method of claim 28 wherein said alternative modulation technology is time division multiple access (TDMA.).

Claim 33

The method of claim 25 wherein said type of action that should be taken is a handoff from said first base station which is communicating at a first frequency with said remote unit using CDMA to said second base station communicating at a second frequency using CDMA.

Claim 34

The method of claim 25 wherein said type of action that should be taken is a handoff from said first base station which is communicating at a first frequency with said remote unit using CDMA to said first base station communicating with said remote unit using an alternative modulation technology.

Claim 35

The method of claim 25 wherein said type of action that should be taken is a handoff from said first base station which is communicating at a first frequency with said remote unit using CDMA to said first base station communicating at a second frequency using CDMA.

Claim 36

The method of claim 25 wherein said active communication signal is comprised of a set of multipath signals each having a different delay and wherein said round trip delay of said active communication signal is the round trip delay corresponding to the earliest arriving multipath signal of said set of multipath signals.

Claim 37

The method of claim 25 further comprising said step of executing said step of accessing when said round trip delay of said active communication signal changes by a predetermined amount.

Claim 38

A communications network comprising: a remote unit through which a network user communicates with another user via at least one base station wherein said remote unit measures a first phase offset of a pilot signal received from a first candidate base station; a first set of base stations including a first base station wherein said first base station measures a round trip delay of an active communication signal between said first base station and said remote unit; a first mobile switching center for controlling communications through said first set of base stations wherein said first mobile switching center receives a message from said remote unit comprising said first phase offset and receives said round trip delay of said active communication signal from said first base station and calculates a candidate round trip delay between said remote unit and said first candidate base station therefrom; an active communication control unit in said first mobile switching center which enters a measurement directed hard handoff state in which said active communication control unit calculates said candidate round trip delay; a measurement directed hard handoff table which is accessed by said active communication control unit to determine, based on said round trip delay corresponding to said active communication signal and said candidate round trip delay, whether the location of said remote unit corresponds to an area where a handoff is desirable; and wherein said measurement directed hard handoff table comprises an entry designating a type of action that should be taken based on a location of said remote unit.

Claim 39

A communications network comprising: a remote unit through which a network user communicates with another user via at least one base station wherein said remote unit measures a first phase offset of a pilot signal received from a first candidate base station; a first set of base stations including a first base station wherein said first base station measures a round trip delay of an active communication signal between said first base station and said remote unit; a first mobile switching center for controlling communications through said first set of base stations wherein said first mobile switching center receives a message from said remote unit comprising said first phase offset and receives said round trip delay of said active communication signal from said first base station and calculates a candidate round trip delay between said remote unit and said first candidate base station therefrom; an active communication control unit in said first mobile switching center which enters a measurement directed hard handoff state in which said active communication control unit calculates said candidate round trip delay; a measurement directed hard handoff table which is accessed by said active communication control unit to determine, based on said round trip delay corresponding to said active communication signal and said candidate round trip delay, whether the location of said remote unit corresponds to an area where a handoff is desirable; and wherein said measurement directed hard handoff table comprises an entry designating a type of action that should be taken based on a location of said remote unit.

Claim 40

The network of claim 36 wherein each of said first set of base stations transmits a common pilot sequence and wherein each of said first set of base stations transmits said common pilot sequence at an identifying channel offset.

Claim 41

The network of claim 37 wherein said first mobile switching center calculates said candidate round trip delay as: RTD.sub.can1 =RTD.sub.ref +2*(pilotphase.sub.can -ChannelOffset.sub.can1 *PilotInc) where: RTD can1 =said candidate round trip delay; RTD ref =said round trip delay of said active communication signal; PilotPhase can1 =said first phase offset; and ChannelOffset can1 * PilotInc=an identifying channel offset corresponding to said first candidate base station.

Claim 42

The network of claim 36 wherein said first candidate base station is controlled by said first mobile switching center.

Claim 43

The network of claim 36 wherein said first candidate base station is controlled by said second mobile switching center.

Claim 44

The network of claim 36 wherein said first candidate base station is controlled by said second mobile switching center and said pilot signal from said first candidate base station is generated by a pilot beacon unit.

Claim 45

The network of claim 36: wherein said remote unit stores a list of active base stations comprising an entry corresponding to each base station with which active communication is established; wherein said remote unit stores a list of candidate base stations comprising an entry corresponding to each base station through which active communication may be possible but is not established and said list of candidate base stations has an entry for said candidate base station; and wherein said remote unit stores a list of neighbor base stations from which said list of candidate base stations is chosen.

Claim 46

The network of claim 36 wherein said active communication control unit is a selector.

Claim 47

The network of claim 36 wherein said remote unit stores a list of active base stations comprising an entry corresponding to each base station with which active communication is established, further comprising a first border set of base stations controlled by said first mobile switching center each have a coverage area that abuts a coverage area corresponding to a base station controlled by said second mobile switching center wherein said active communication control unit enters said measurement directed hard handoff state only when said list of active base stations comprises an entry corresponding to one of said first border set of base stations.

Claim 48

The network of claim 36 wherein said remote unit stores a list of active base stations comprising an entry corresponding to each base station with which active communication is established, further comprising a first border set of base stations controlled by said first mobile switching center each have a coverage area that abuts a coverage area corresponding to a base station controlled by said second mobile switching center wherein said active communication control unit enters said measurement directed hard handoff state when each entry on said list of active base stations corresponds to said first border set of base stations.

Claim 49

The network of claim 36 wherein said remote unit stores a list of active base stations comprising an entry corresponding to each base station with which active communication is established further comprising a first border set of base stations controlled by said first mobile switching center each have a coverage area that abuts a coverage area corresponding to a base station controlled by said second mobile switching center wherein said active communication control unit enters said measurement directed hard handoff state only when said list of active base stations comprises a single entry and said single entry corresponds to one of said first border set of base stations.

Claim 50

The network of claim 36 further comprising a measurement directed hard handoff table which is accessed by said active communication control unit to determine a location of said remote unit based on said round trip delay corresponding to said active communication signal and said candidate round trip delay.

Claim 51

The network of claim 36 wherein said type of action that should be taken is a handoff from said first base station which is communicating with said remote unit using code division multiple access (CDMA) to said second base station operating using an alternative modulation technology.

Claim 52

The network of claim 48 wherein said alternative modulation technology is frequency modulation (FM.).

Claim 53

The network of claim 48 wherein said alternative modulation technology is time division multiple access (TDMA.).

Claim 54

The network of claim 36 wherein said type of action that should be taken is a handoff from said first base station which is communicating at a first frequency with said remote unit using CDMA to said second base station communicating at a second frequency using CDMA.

Claim 55

The network of claim 36 wherein said type of action that should be taken is a handoff from said first base station which is communicating at a first frequency with said remote unit using CDMA to said first base station communicating with said remote unit using an alternative modulation technology.

Claim 56

The network of claim 36 wherein said type of action that should be taken is a handoff from said first base station which is communicating at a first frequency with said remote unit using CDMA to said first base station communicating at a second frequency using CDMA.

Claim 57

The network of claim 36 wherein said active communication signal is comprised of a set of multipath signals each having a different delay and wherein said round trip delay of said active communication signal is the round trip delay corresponding to the earliest arriving multipath signal of said set of multipath signals.

Claim 58

The network of claim 36 wherein said measurement directed hard handoff table is accessed when said round trip delay of said active communication signal changes by a predetermined amount.

Claim 59

The apparatus of claim 36 wherein said measurement directed hard handoff table is accessed whenever said first mobile switching center receives said message from said remote unit comprising said first phase offset.

Claim 60

The network of claim 36 wherein said active communication signal is a spread spectrum signal which is spread by a pseudorandom noise (PN) sequence and wherein said round trip delay of said active communication signal is measured in PN chips.

Claim 61

The network of claim 37 wherein said active communication signal is a spread spectrum signal which is spread by a pseudorandom noise (PN) sequence and wherein said round trip delay of said active communication signal is measured in PN chips, said identifying channel offset is measured in PN chips, and said candidate round trip delay is measured in PN chips.

Claim 62

A communications network comprising: a remote unit through which a network user communicates with another user via at least one base station; a first and second mobile switching centers for respectively controlling communications through a first set of base stations and through a second set of base stations including a second base station; a first base station which is a member of said first set of base stations which measures a round trip delay of an active communication signal between said first base station and said remote unit; an active communication control unit located in said first mobile switching center having a measurement directed hard handoff state in which said active communication control unit accesses a measurement directed hard handoff table to determine based on said round trip delay corresponding to said active communication signal whether a location of said remote unit corresponds to an area where a handoff is desirable; wherein said measurement directed hard handoff table comprises an entry specifying a type of action that should be taken based on said location of said remote unit.

Claim 63

A communications network comprising: a remote unit through which a network user communicates with another user via at least one base station; a first and second mobile switching centers for respectively controlling communications through a first set of base stations and through a second set of base stations including a second base station; a first base station which is a member of said first set of base stations which measures a round trip delay of an active communication signal between said first base station and said remote unit; an active communication control unit located in said first mobile switching center having a measurement directed hard handoff state in which said active communication control unit accesses a measurement directed hard handoff table to determine based on said round trip delay corresponding to said active communication signal whether a location of said remote unit corresponds to an area where a handoff is desirable; wherein said measurement directed hard handoff table comprises an entry specifying a type of action that should be taken based on said location of said remote unit.

Claim 64

The network of claim 59 wherein each of said first set of base stations transmits a common pilot sequence and wherein each of said first set of base stations transmits said common pilot sequence at an identifying channel offset.

Claim 65

The network of claim 59 wherein said active communication control unit is a selector.

Claim 66

The network of claim 59 wherein said type of action that should be taken is a handoff from said first base station which is communicating with said remote unit using code division multiple access (CDMA) to said second base station operating using an alternative modulation technology.

Claim 67

The network of claim 62 wherein said alternative modulation technology is frequency modulation (FM.).

Claim 68

The network of claim 62 wherein said alternative modulation technology is time division multiple access (TDMA.).

Claim 69

The network of claim 59 wherein said type of action that should be taken is a handoff from said first base station which is communicating at a first frequency with said remote unit using CDMA to said second base station communicating at a second frequency using CDMA.

Claim 70

The network of claim 59 wherein said type of action that should be taken is a handoff from said first base station which is communicating at a first frequency with said remote unit using CDMA to said first base station communicating with said remote unit using an alternative modulation technology.

Claim 71

The network of claim 59 wherein said type of action that should be taken is a handoff from said first base station which is communicating at a first frequency with said remote unit using CDMA to said first base station communicating at a second frequency using CDMA.

Claim 72

The network of claim 59 wherein said active communication signal is comprised of a set of multipath signals each having a different delay and wherein said round trip delay of said active communication signal is the round trip delay corresponding to the earliest arriving multipath signal of said set of multipath signals.

Claim 73

The network of claim 59 wherein said active communication signal accesses said measurement directed hard handoff table when said round trip delay of said active communication signal changes by a predetermined amount.

Claim 74

In a communications network in which a network user communicates through a remote unit with another user via at least one base station, said network including first and second mobile switching centers for respectively controlling communications through a first set of base stations including a first base station and through a second set of base stations including a second base station, a method for directing communications between said remote unit and said first and second base stations comprising the steps of: measuring at said first base station a round trip delay of an active communication signal between said first base station and said remote unit; measuring at said remote unit a first phase offset of a pilot signal received from a first candidate base station; reporting by said remote unit to said first mobile switching center via said first base station said first phase offset; and calculating at said first mobile switching center a candidate round trip delay between said remote unit and said first candidate base station based on said first phase offset and said round trip delay of said active communication signal; storing at said remote unit a list of active base stations comprising an entry corresponding to each base station with which active communication is established; storing at said remote unit a list of candidate base stations comprising an entry corresponding to each base station through which active communication may be possible but is not established and said list of candidate base stations has an entry for said first candidate base station; and storing at said remote unit a list of neighbor base stations from which said list of candidate base stations is chosen; measuring at said remote unit a power level of a pilot signal corresponding to a first entry on said list of neighbor base stations and if said power level exceeds an add threshold said first entry on said list of neighbor base stations is added to said list of candidate base stations; and wherein if said remote unit is communicating with one of a first border set of base stations controlled by said first mobile switching center, each of said first border set of base stations having a coverage area that abuts a coverage area corresponding to a base station controlled by said second mobile switching center, said remote unit has a lower value of said add threshold than other remote units communicating with at least one base station of said first set of base stations.

Claim 75

In a communications network in which a network user communicates through a remote unit with another user via at least one base station, said network including first and second mobile switching centers for respectively controlling communications through a first set of base stations including a first base station and through a second set of base stations including a second base station, a method for directing communications between said remote unit and said first and second base stations comprising the steps of: measuring at said first base station a round trip delay of an active communication signal between said first base station and said remote unit; measuring at said remote unit a first phase offset of a pilot signal received from a first candidate base station; reporting by said remote unit to said first mobile switching center via said first base station said first phase offset; and calculating at said first mobile switching center a candidate round trip delay between said remote unit and said first candidate base station based on said first phase offset and said round trip delay of said active communication signal; storing at said remote unit a list of active base stations comprising an entry corresponding to each base station with which active communication is established; storing at said remote unit a list of candidate base stations comprising an entry corresponding to each base station through which active communication may be possible but is not established and said list of candidate base stations has an entry for said first candidate base station; and storing at said remote unit a list of neighbor base stations from which said list of candidate base stations is chosen; measuring at said remote unit a power level of a pilot signal corresponding to a first entry on said list of neighbor base stations and if said power level exceeds an add threshold said first entry on said list of neighbor base stations is added to said list of candidate base stations; and wherein if said remote unit is communicating with one of a first border set of base stations controlled by said first mobile switching center, each of said first border set of base stations having a coverage area that abuts a coverage area corresponding to a base station controlled by said second mobile switching center, said remote unit has a lower value of said add threshold than other remote units communicating with at least one base station of said first set of base stations.

Claim 76

In a communications network in which a network user communicates through a remote unit with another user via at least one base station, said network including first and second mobile switching centers for respectively controlling communications through a first set of base stations including a first base station and through a second set of base stations including a second base station, a method for directing communications between said remote unit and said first and second base stations comprising the steps of: measuring at said first base station a round trip delay of an active communication signal between said first base station and said remote unit; measuring at said remote unit a first phase offset of a pilot signal received from a first candidate base station; reporting by said remote unit to said first mobile switching center via said first base station said first phase offset; and calculating at said first mobile switching center a candidate round trip delay between said remote unit and said first candidate base station based on said first phase offset and said round trip delay of said active communication signal; storing at said remote unit a list of active base stations comprising an entry corresponding to each base station with which active communication is established; storing at said remote unit a list of candidate base stations comprising an entry corresponding to each base station through which active communication may be possible but is not established and said list of candidate base stations has an entry for said first candidate base station; and storing at said remote unit a list of neighbor base stations from which said list of candidate base stations is chosen; measuring by said remote unit a power level of said first base station and if said power level is less than a drop threshold an entry on said list of active base stations corresponding to said first base station is removed; and wherein if said remote unit is communicating with one of a first border set of base stations controlled by said first mobile switching center, each of said first border set of base stations having a coverage area that abuts a coverage area corresponding to a base station controlled by said second mobile switching center, said remote unit has a lower value of said drop threshold than other remote units communicating with at least one of said first set of base stations.

Claim 77

In a communications network in which a network user communicates through a remote unit with another user via at least one base station, said network including first and second mobile switching centers for respectively controlling communications through a first set of base stations including a first base station and through a second set of base stations including a second base station, a method for directing communications between said remote unit and said first and second base stations comprising the steps of: measuring at said first base station a round trip delay of an active communication signal between said first base station and said remote unit; measuring at said remote unit a first phase offset of a pilot signal received from a first candidate base station; reporting by said remote unit to said first mobile switching center via said first base station said first phase offset; and calculating at said first mobile switching center a candidate round trip delay between said remote unit and said first candidate base station based on said first phase offset and said round trip delay of said active communication signal; storing at said remote unit a list of active base stations comprising an entry corresponding to each base station with which active communication is established; storing at said remote unit a list of candidate base stations comprising an entry corresponding to each base station through which active communication may be possible but is not established and said list of candidate base stations has an entry for said first candidate base station; and storing at said remote unit a list of neighbor base stations from which said list of candidate base stations is chosen; measuring by said remote unit a power level of said first base station and if said power level is less than a drop threshold an entry on said list of active base stations corresponding to said first base station is removed; and wherein if said remote unit is communicating with one of a first border set of base stations controlled by said first mobile switching center, each of said first border set of base stations having a coverage area that abuts a coverage area corresponding to a base station controlled by said second mobile switching center, said remote unit has a lower value of said drop threshold than other remote units communicating with at least one of said first set of base stations.

Claim 78

In a communications network in which a network user communicates through a remote unit with another user via at least one base station, said network including first and second mobile switching centers for respectively controlling communications through a first set of base stations including a first base station and through a second set of base stations including a second base station, a method for directing communications between said remote unit and said first and second base stations comprising the steps of: measuring at said first base station a round trip delay of an active communication signal between said first base station and said remote unit; measuring at said remote unit a first phase offset of a pilot signal received from a first candidate base station; reporting by said remote unit to said first mobile switching center via said first base station said first phase offset; and calculating at said first mobile switching center a candidate round trip delay between said remote unit and said first candidate base station based on said first phase offset and said round trip delay of said active communication signal; storing at said remote unit a list of active base stations comprising an entry corresponding to each base station with which active communication is established; storing at said remote unit a list of candidate base stations comprising an entry corresponding to each base station through which active communication may be possible but is not established and said list of candidate base stations has an entry for said first candidate base station; storing at said remote unit a list of neighbor base stations from which said list of candidate base stations is chosen; measuring at said remote unit a power level of said first base station and if said power level is less than a drop threshold for longer than a predetermined amount of time, an entry on said list of active base stations corresponding to said first base station is removed; and wherein if said remote unit is in communication with one of a first border set of base stations controlled by said first mobile switching center, each of said first border set of base stations having a coverage area that abuts a coverage area corresponding to a base station controlled by said second mobile switching center, said remote unit has a longer value of said predetermined amount of time than other remote units communicating with at least one base station of said first set of base stations.

Claim 79

In a communications network in which a network user communicates through a remote unit with another user via at least one base station, said network including first and second mobile switching centers for respectively controlling communications through a first set of base stations including a first base station and through a second set of base stations including a second base station, a method for directing communications between said remote unit and said first and second base stations comprising the steps of: measuring at said first base station a round trip delay of an active communication signal between said first base station and said remote unit; measuring at said remote unit a first phase offset of a pilot signal received from a first candidate base station; reporting by said remote unit to said first mobile switching center via said first base station said first phase offset; and calculating at said first mobile switching center a candidate round trip delay between said remote unit and said first candidate base station based on said first phase offset and said round trip delay of said active communication signal; storing at said remote unit a list of active base stations comprising an entry corresponding to each base station with which active communication is established; storing at said remote unit a list of candidate base stations comprising an entry corresponding to each base station through which active communication may be possible but is not established and said list of candidate base stations has an entry for said first candidate base station; storing at said remote unit a list of neighbor base stations from which said list of candidate base stations is chosen; measuring at said remote unit a power level of said first base station and if said power level is less than a drop threshold for longer than a predetermined amount of time, an entry on said list of active base stations corresponding to said first base station is removed; and wherein if said remote unit is in communication with one of a first border set of base stations controlled by said first mobile switching center, each of said first border set of base stations having a coverage area that abuts a coverage area corresponding to a base station controlled by said second mobile switching center, said remote unit has a longer value of said predetermined amount of time than other remote units communicating with at least one base station of said first set of base stations.

Claim 80

A communications network comprising: a remote unit through which a network user communicates with another user via at least one base station wherein said remote unit measures a first phase offset of a pilot signal received from a first candidate base station; a first set of base stations including a first base station wherein said first base station measures a round trip delay of an active communication signal between said first base station and said remote unit; a first mobile switching center for controlling communications through said first set of base stations wherein said first mobile switching center receives a message from said remote unit comprising said first phase offset and receives said round trip delay of said active communication signal from said first base station and calculates a candidate round trip delay between said remote unit and said first candidate base station therefrom; a second set of base stations including a second base station; a second mobile switching center for controlling communications through said second set of base stations; wherein said remote unit stores a list of active base stations comprising an entry corresponding to each base station with which active communication is established; wherein said remote unit stores a list of candidate base stations comprising an entry corresponding to each base station through which active communication may be possible but is not established and said list of candidate base stations has an entry for said candidate base station; wherein said remote unit stores a list of neighbor base stations from which said list of candidate base stations is chosen; wherein said remote unit measures a power level of a pilot signal corresponding to a first entry on said list of neighbor base stations and if said power level exceeds an add threshold said first entry on said list of neighbor base stations is added to said list of candidate base stations; and wherein if said remote unit is communicating with one of a first border set of base stations controlled by said first mobile switching center, each of said first border set of base stations having a coverage area that abuts a coverage area corresponding to a base station controlled by said second mobile switching center, said remote unit has a lower value of said add threshold than other remote units communicating with at least one base station of said first set of base stations.

Claim 81

A communications network comprising: a remote unit through which a network user communicates with another user via at least one base station wherein said remote unit measures a first phase offset of a pilot signal received from a first candidate base station; a first set of base stations including a first base station wherein said first base station measures a round trip delay of an active communication signal between said first base station and said remote unit; a first mobile switching center for controlling communications through said first set of base stations wherein said first mobile switching center receives a message from said remote unit comprising said first phase offset and receives said round trip delay of said active communication signal from said first base station and calculates a candidate round trip delay between said remote unit and said first candidate base station therefrom; a second set of base stations including a second base station; a second mobile switching center for controlling communications through said second set of base stations; wherein said remote unit stores a list of active base stations comprising an entry corresponding to each base station with which active communication is established; wherein said remote unit stores a list of candidate base stations comprising an entry corresponding to each base station through which active communication may be possible but is not established and said list of candidate base stations has an entry for said candidate base station; wherein said remote unit stores a list of neighbor base stations from which said list of candidate base stations is chosen; wherein said remote unit measures a power level of a pilot signal corresponding to a first entry on said list of neighbor base stations and if said power level exceeds an add threshold said first entry on said list of neighbor base stations is added to said list of candidate base stations; and wherein if said remote unit is communicating with one of a first border set of base stations controlled by said first mobile switching center, each of said first border set of base stations having a coverage area that abuts a coverage area corresponding to a base station controlled by said second mobile switching center, said remote unit has a lower value of said add threshold than other remote units communicating with at least one base station of said first set of base stations.

Claim 82

A communications network comprising: a remote unit through which a network user communicates with another user via at least one base station wherein said remote unit measures a first phase offset of a pilot signal received from a first candidate base station; a first set of base stations including a first base station wherein said first base station measures a round trip delay of an active communication signal between said first base station and said remote unit; a first mobile switching center for controlling communications through said first set of base stations wherein said first mobile switching center receives a message from said remote unit comprising said first phase offset and receives said round trip delay of said active communication signal from said first base station and calculates a candidate round trip delay between said remote unit and said first candidate base station therefrom; a second set of base stations including a second base station; a second mobile switching center for controlling communications through said second set of base stations; wherein said remote unit stores a list of active base stations comprising an entry corresponding to each base station with which active communication is established; wherein said remote unit stores a list of candidate base stations comprising an entry corresponding to each base station through which active communication may be possible but is not established and said list of candidate base stations has an entry for said candidate base station; wherein said remote unit stores a list of neighbor base stations from which said list of candidate base stations is chosen; wherein said remote unit measures a power level of said first base station and if said power level is less than a drop threshold an entry on said list of active base stations corresponding to said first base station is removed; and wherein if said remote unit is communicating with one of a first border set of base stations controlled by said first mobile switching center, each of said first border set of base stations having a coverage area that abuts a coverage area corresponding to a base station controlled by said second mobile switching center, said remote unit has a lower value of said drop threshold than other remote units communicating with at least one of said first set of base stations.

Claim 83

A communications network comprising: a remote unit through which a network user communicates with another user via at least one base station wherein said remote unit measures a first phase offset of a pilot signal received from a first candidate base station; a first set of base stations including a first base station wherein said first base station measures a round trip delay of an active communication signal between said first base station and said remote unit; a first mobile switching center for controlling communications through said first set of base stations wherein said first mobile switching center receives a message from said remote unit comprising said first phase offset and receives said round trip delay of said active communication signal from said first base station and calculates a candidate round trip delay between said remote unit and said first candidate base station therefrom; a second set of base stations including a second base station; a second mobile switching center for controlling communications through said second set of base stations; wherein said remote unit stores a list of active base stations comprising an entry corresponding to each base station with which active communication is established; wherein said remote unit stores a list of candidate base stations comprising an entry corresponding to each base station through which active communication may be possible but is not established and said list of candidate base stations has an entry for said candidate base station; wherein said remote unit stores a list of neighbor base stations from which said list of candidate base stations is chosen; wherein said remote unit measures a power level of said first base station and if said power level is less than a drop threshold an entry on said list of active base stations corresponding to said first base station is removed; and wherein if said remote unit is communicating with one of a first border set of base stations controlled by said first mobile switching center, each of said first border set of base stations having a coverage area that abuts a coverage area corresponding to a base station controlled by said second mobile switching center, said remote unit has a lower value of said drop threshold than other remote units communicating with at least one of said first set of base stations.

Claim 84

A communications network comprising: a remote unit through which a network user communicates with another user via at least one base station wherein said remote unit measures a first phase offset of a pilot signal received from a first candidate base station; a first set of base stations including a first base station wherein said first base station measures a round trip delay of an active communication signal between said first base station and said remote unit; a first mobile switching center for controlling communications through said first set of base stations wherein said first mobile switching center receives a message from said remote unit comprising said first phase offset and receives said round trip delay of said active communication signal from said first base station and calculates a candidate round trip delay between said remote unit and said first candidate base station therefrom; a second set of base stations including a second base station; a second mobile switching center for controlling communications through said second set of base stations; wherein said remote unit stores a list of active base stations comprising an entry corresponding to each base station with which active communication is established; wherein said remote unit stores a list of candidate base stations comprising an entry corresponding to each base station through which active communication may be possible but is not established and said list of candidate base stations has an entry for said candidate base station; wherein said remote unit stores a list of neighbor base stations from which said list of candidate base stations is chosen; wherein said remote unit measures a power level of said first base station and if said power level is less than a drop threshold for longer than a predetermined amount of time, an entry on said list of active base stations corresponding to said first base station is removed; and wherein if said remote unit is in communication with one of a first border set of base stations controlled by said first mobile switching center, each of said first border set of base stations having a coverage area that abuts a coverage area corresponding to a base station controlled by said second mobile switching center, said remote unit has a longer value of said predetermined amount of time than other remote units communicating with at least one base station of said first set of base stations.

Claim 85

A communications network comprising: a remote unit through which a network user communicates with another user via at least one base station wherein said remote unit measures a first phase offset of a pilot signal received from a first candidate base station; a first set of base stations including a first base station wherein said first base station measures a round trip delay of an active communication signal between said first base station and said remote unit; a first mobile switching center for controlling communications through said first set of base stations wherein said first mobile switching center receives a message from said remote unit comprising said first phase offset and receives said round trip delay of said active communication signal from said first base station and calculates a candidate round trip delay between said remote unit and said first candidate base station therefrom; a second set of base stations including a second base station; a second mobile switching center for controlling communications through said second set of base stations; wherein said remote unit stores a list of active base stations comprising an entry corresponding to each base station with which active communication is established; wherein said remote unit stores a list of candidate base stations comprising an entry corresponding to each base station through which active communication may be possible but is not established and said list of candidate base stations has an entry for said candidate base station; wherein said remote unit stores a list of neighbor base stations from which said list of candidate base stations is chosen; wherein said remote unit measures a power level of said first base station and if said power level is less than a drop threshold for longer than a predetermined amount of time, an entry on said list of active base stations corresponding to said first base station is removed; and wherein if said remote unit is in communication with one of a first border set of base stations controlled by said first mobile switching center, each of said first border set of base stations having a coverage area that abuts a coverage area corresponding to a base station controlled by said second mobile switching center, said remote unit has a longer value of said predetermined amount of time than other remote units communicating with at least one base station of said first set of base stations.

Claim 86

The method of claim 1 wherein said first base station defines a first coverage area and wherein said first coverage area contracts in size when the number of remote units communicating with said first base station increases.

Claim 87

The method of claim 1 further comprising the step of deploying at said first base station a base station breathing function for balancing a forward link coverage area to a reverse link coverage area.

Claim 88

The method of claim 1 wherein a first border set of base stations controlled by said first mobile switching center each have a coverage area that abuts a coverage area corresponding to a base station controlled by said second mobile switching center, further comprising the step of deploying at said first base station, if said first base station is one of said first border set of base stations, a border base station breathing function for balancing a forward link coverage area to a reverse link coverage area which is different from a base station breathing function deployed by other base stations of said first set of base stations.

Claim 89

The network of claim 36 wherein said first base station defines a first coverage area and wherein said first coverage area contracts in size when the number of remote units communicating with said first base station increases.

Claim 90

The network of claim 36 wherein said first base station deploys a base station breathing function for balancing a forward link coverage area to a reverse link coverage area.

Claim 91

The network of claim 36 further comprising a first border set of base stations controlled by said first mobile switching center, each of said first border set of base stations have a coverage area that abuts a coverage area corresponding to a base station controlled by said second mobile switching center and wherein said first base station is one of said first border set of base stations and said first base station deploys a first base station breathing function for balancing a forward link coverage area to a reverse link coverage area which is different from a base station breathing function deployed by other base stations of said first set of base stations.