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 ▼

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. vice characteristics to the second data packet where it is determined that the second data packet corresponds to the given micro flow. 2. The method of claim 1, wherein determining whether the second data packet corresponds to the given micro flow includes examining a set of identifying information found in the second data packet. 3. The method of claim 1, further comprising: maintaining a flow block that stores the set of quality of service characteristics. 4. The method of claim 3, wherein the flow block is maintained in a flow block table that associates the set of quality of service characteristics to packets in the given micro flow. 5. The method of claim 4, wherein network layer and transport layer information are retrieved from data packets and used to correlate them to the given micro flow. 6. The method of claim 5, wherein a hash key is generated from the network layer and transport layer information, and the hash key is used to identify the flow block in the flow block table. 7. The method of claim 1, wherein the set of quality of service characteristics includes a transmission rate constraint. 8. The method of claim 1, wherein the set of quality of service characteristics includes a delay variation constraint. 9. The method of claim 7, wherein the transmission rate constraint is compared to a determined rate for packets in the given micro flow, and wherein the second data packet is discarded where the determined rate for the second data packet exceeds the transmission rate constraint. 10. The method of claim 9, wherein the determined rate is derived from an arrival rate for packets in the given micro flow into a switch corresponding to the network hop. 11. The method of claim 1, further comprising: using the set of quality of service characteristics to selectively apply a queuing technique to the given micro flow to adjust the transmission rate of the given micro flow. 12. The method of claim 11, wherein the queuing technique includes weighted fair queuing. 13. The method of claim 9, further comprising: retrieving path information for the given micro flow prior to comparing the determined rate to the transmission rate constraint. 14. The method of claim 1, further comprising: after the first data packet is received at the network hop, identifying a next network hop by determining whether a candidate network hop can accommodate transmission of packets in the given micro flow according to the set of quality of service characteristics. 15. The method of claim 1, wherein the first data packet and the second data packet are IP packets. 16. The method of claim 1, wherein the first data packet and the second data packet are deencapsulated after they are received from a trunk line. 17. The method of claim 1, further comprising: extracting policy information from the first data packet; and adjusting the value of at least one of the set of quality of service characteristics based upon the extracted policy information. 18. The method of claim 1, wherein extracting the set of quality of service characteristics comprises extracting layer information from the first data packet, and determining the set of quality of service characteristics from stored information relating quality of service characteristics to layer information. 19. A line card for routing a micro-flow in a network comprising a plurality of network hops, the line card comprising the steps of: an interface, configured to receive at a network hop a first data packet and a second data packet; a micro flow classifier, in operative communication with the interface, configured to establish the first data packet as corresponding to a given micro flow, extract a set of quality of service characteristics from the first data packet; and a micro flow recognizer, in operative communication with the interface and the micro flow classifier, configured to retain the set of quality of service characteristics in association with the given micro flow