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.At higher ratesthe channel rate is given in a service connect message for the traffic channel or extended channel assignment messages (see the following section).4.5 cdma2000 QoS4.5.1 Basic StandardCdma2000, as defined up to version 3X Release A, has less explicit supportfor QoS distinctions than does WCDMA.As cdma2000 is backwards com-patible with cdmaOne, the quality available depends on the generations ofequipment involved; for example, IS-95 B dedicated channels are limited toone fixed rate FCH and up to seven fixed rate SCH in either direction, giv-ing a maximum possible data rate of 76.8 Kbps, whereas variable rates up to614 Kbps for 1X and 2 Mbps for 3X are possible.From a data user’s perspec-tive, the most important QoS factor is likely to be the data rate (Table 4.6), and this depends heavily on the mobile’s radio configuration.Because of thelarge number of possibilities, the message transmission must be preceded byan exchange of service request and response messages between the mobileand base stations to establish the radio configuration, multiplexing options, and frequency bands that can be supported, with the final selection to beused being passed back from the base to the mobile in the service connectmessage.For radio configuration classes 2 and 3 this will indicate the actual transmission rate to be used on the FCH or SCH.Frequently the mobile is88QoS in Integrated 3G NetworksTable 4.7Data Rates for Spreading Rate 1 (cdma2000 1X)Channel TypeData Rates (bps)Access channel4,800Enhanced access channelHeader9,600Data38,400 (5-, 10-, or 20-ms frames),19,200 (10- or 20-ms frames), or9,600 (20-ms frames)Reverse common control channel38,400 (5-, 10-, or 20-ms frames),19,200 (10- or 20-ms frames), or9,600 (20-ms frames)Reverse dedicated control channelRC 39,600RC 414,400 (20-ms frames) or9,600 (5-ms frames)Reverse fundamental channelRC 19,600, 4,800, 2,400, or 1,200RC 214,400, 7,200, 3,600, or 1,800RC 39,600, 4,800, 2,700,or 1,500 (20-ms)9,600 (5-ms frames)RC 414,400, 7,200, 3,600, or 1,800 (20ms) or9,600 (5-ms frames)Reverse supplemental code channelRC 19,600RC 214,400Reverse supplemental channelRC 3307,200, 153,600, 76,800, 38,400, 19,200,9,600, 4,800, 2,700, or 1,500 (20-ms frames)153,600, 76,800, 38,400, 19,200, 9,600,4,800, 2,400, or 1,350 (40-ms frames)76,800, 38,400, 19,200, 9,600, 4,800, 2,400,or 1,200 (80-ms frames)Reverse supplemental channelRC 4230,400, 115,200, 57,600, 28,800, 14,400,7,200, 3,600, or 1,800 (20-ms frames)115,200, 57,600, 28,800, 14,400, 7,200,3,600, or 1,800 (40-ms frames)57,600, 28,800, 14,400, 7,200, 3,600, or1,800 (80-ms frames)Source: [5].cdma200089Table 4.8Data Rates for Spreading Rate 3 (cdma2000 3X)Channel TypeData Rates (bps)Enhanced access channelHeader9,600Data38,400 (5-, 10-, or 20-ms frames), 19,200 (10-or 20-ms frames), or 9,600 (20-ms frames)Reverse common control channel38,400 (5-, 10-, or 20-ms frames), 19,200 (10-or 20-ms frames), or 9,600 (20-ms frames)Reverse dedicated control channel RC 59,600RC 614,400 (20-ms frames) or 9,600 (5-ms frames)Reverse fundamental channelRC 59,600, 4,800, 2,700, or 1,500 (20 ms) or 9,600(5-ms frames)RC 614,400, 7,200, 3,600, or 1,800 (20 ms) or 9,600(5-ms frames)Reverse supplemental channelRC 5614,400, 307,200, 153,600, 76,800, 38,400,19,200, 9,600, 4,800, 2,700, or 1,500 (20-msframes); 307,200, 153,600, 76,800, 38,400,19,200, 9,600, 4,800, 2,400, or 1,350 (40-msframes); 153,600, 76,800, 38,400, 19,200,9,600, 4,800, 2,400, or 1,200 (80 ms-frames)RC 61,036,800, 460,800, 230,400, 115,200, 57,600,28,800, 14,400, 7,200, 3,600, or 1,800 (20 ms);518,400, 230,400, 115,200, 57,600, 28,800,14,400, 7,200, 3,600, or 1,800 (40-ms frames);259,200, 115,200, 57,600, 28800, 14,400,7,200, 3,600, or 1,800 (80-ms frames)Source: [5].instructed to start with a default configuration based on multiplexing option 1 prior to receipt of the service connect message.The rates and frame error rates (in extended cases) are included inchannel assignment messages (CAM), extended CAM (ECAM), SCAM, andextended SCAM (ESCAM).CAM and ECAM apply to the initial channels,such as the fundamental channel, while SCAM and ESCAM apply to theextra channels acquired to support high data rates.ECAM and ESCAMare only supported by mobiles capable of configurations additional to RC 1and 2.90QoS in Integrated 3G NetworksThe BTS can assign a mobile up to seven supplemental code channelsfor RC 1 or 2, but only a maximum of two supplemental channels (at muchhigher speed) for the later configurations.Rates for the SCH are notified in the ESCAMs and are quoted with theirrate fields in Table 4.9 [4].They also correspond to specific combinations of multiplex option and radio configuration, which determine rates in general.RC 1 and 2 only support fixed rate supplemental code channels at 9.6and 14.4 Kbps, respectively.The LAC also specifies the target frame qualityto be used by forward link power control (FPC) in the ESCAM.This isbased on a 5-bit field with values as shown in Table 4.10 [ Pobierz całość w formacie PDF ]