C Radio Access Network VolP Optimization CDF of UE Tx Power with 60 UEs Continuous DPCCH Gating DPCCH UE Tx Power (dBm) Figure 10.16 UE power CDF distributions with 60 UEs/cell for gating DPCCH and continuous DPCCH. on the activity of DPCCH, which is affected by the transmission of E-DCH and HS-DPCCH. It also implies that the frequent CQI reporting carried on HS-DPCCH would reduce the power savings gain because of having fewer opportunities to use DPCCH gating. Similarly, if the DL data transmission over HS-DSCH is quite active, the transmission of ACK/NAK feedback information carried over HS-DPCCH in the UL would be quite frequent, which will also constrain the gating gain. Table 10.5 summarizes the VoIP capacity results obtained with a quasi-static system simulator for both 2 ms and 10 ms TTI in the case of 3 kmph UE moving speed. The capacity is calculated with two different criteria presented in Section 10.3.3: the number of VoIP users per sector not exceeding the 5% FER target measured over 10 S or the number of VoIP users allowed per sector with an aver- age noise rise of 6 dB. Here the delay budget of 80 ms is assumed for HSUPA. This would not be the bottleneck at the performance since HARQ retransmissions will be completed within this delay budget when the maximum allowed HARQ retransmission number is 1 for 10 ms TTI and 3 for 2 ms TTI. The results show that VoIP capacity over HSUPA is comparable to or to a great extent better than CS © 2009 by Taylor & Francis Group, LLC Table 10.5 Summary of the UL VolP Capacity Results without and with UL DPCCH Gating Capacity Criteria: 5% FER Over 10 S Capacity Criteria: Noise Rise 6 dB Continuous Gated Average Number Continuous DPCCH Gated DPCCH Gating DPCCH DPCCH Gating of Transmissions (Users) (Users) Gain (%) (Users) (Users) Gain (%) 10 ms* 10ms TTI results using bundling of 2 VolP frames in a single TTI. Source: 3GPP TR 25.903 V1.0.0 (2006-05). "Continuous connectivity for packet data users." © 2009 by Taylor & Francis Group, LLC Radio Access Network VolP Optimiz