초록 ▼

Inter-frequency handoffs in a CDMA or other wireless communication system are controlled using a noise-limited coverage trigger metric which is able to distinguish between same-frequency cell boundaries and other-frequency cell boundaries in the system. The trigger metric may be generated as a funct

Inter-frequency handoffs in a CDMA or other wireless communication system are controlled using a noise-limited coverage trigger metric which is able to distinguish between same-frequency cell boundaries and other-frequency cell boundaries in the system. The trigger metric may be generated as a function of an average signal-to-noise measure for pilot signals received at a mobile station of the system and a linear sum of the signal-to-noise measures. The signal-to-noise measures may be generated in the mobile station and included in messages transmitted from the mobile station to one or more base stations of the system. The trigger metric is used to control a handoff from a current frequency to a new frequency in an ongoing call. The trigger metric may alternatively be based on a measure of mobile receive power alone. Other aspects of the invention reduce unnecessary searching for a new frequency and decrease the likelihood of "ping-ponging" from a current frequency to a new frequency by providing additional checks in the handoff process. For example, receive power and pilot signal-to-noise measures may be generated at a mobile station for both current and new frequencies. The mobile station then continues to operate at the current frequency as long as certain predetermined threshold conditions based on the measures are satisfied.

대표청구항 ▼

[ What is claimed is:] [11.]11. A method of controlling a frequency handoff in a wireless communication system in which a mobile station communicates with one or more base stations, the method comprising the steps of:generating measures of at least one of receive power and pilot signal-to-noise for

[ What is claimed is:] [11.]11. A method of controlling a frequency handoff in a wireless communication system in which a mobile station communicates with one or more base stations, the method comprising the steps of:generating measures of at least one of receive power and pilot signal-to-noise for each of a current frequency and a new frequency; andutilizing at least a subset of the measures to obtain a trigger metric configured so as to distinguish same-frequency boundaries of the system from other-frequency boundaries of the system, the trigger metric being generated utilizing an average transmit signal-to-noise measure for a plurality of pilot signals and a sum of signal-to-noise measures for at least a subset of the plurality of pilot signals, the trigger metric being used to determine if an ongoing call involving the mobile station should continue to operate at the current frequency or be handed off to the new frequency.