veral seconds until all segments are received by the UE and reselection to LTE is activated. Before the activation, pre-Rel8 cell ranking-based reselection is used. This often results in UE reselecting first from 2G to 3G instead of moving directly to LTE. Approaches to accelerate delivery of SI2quarter segments to UE are to use minimal number of LTE and 3G frequencies in SI2quarter (fitting to one segment) and deploy the so-called extended BCCH which effectively increases the scheduling rate of SI2quarter. After priority-based cell reselection has been activated, the time to reselect to a cell in a higher priority LTE or UTRAN layer must be shorter than 70 + reselection seconds, where the minimum value of reselection is 5 seconds. Every additional LTE or UTRAN higher priority layer adds another 70 seconds to the requirement. Therefore, the time requirements for 2G to LTE reselection are very loose. In practice, however, UEs tend to reselect to LTE faster than the 3GPP requirement after the priority-based reselection has been activated (all SI2quarter segments with received). Inter-RAT Redirect and PS HO from 2G/3G to LTE Similarly as from LTE to 3G, it is possible to use RRC release with redirect to quickly move UE from 3G to LTE or from 2G to LTE. In the radio connection release message the target RAT carrier frequency information is included. Depending on RNC and BSC implementation, LTE measurements, if supported by the UE, may be performed prior to RRC release. In normal radio conditions, the time from radio connection release in 3G to send Tracking Area Update in LTE is at most a few hundred milliseconds. Also handover from 2G and 3G to LTE is possible, if supported by the system and UE. The triggering of the measurements and the handover are based on UE capability and LTE Small Cell Optimization Return time to LTE after CSFB call, measurement example normal cell reselection blind redirect measurement-based redirect Return time to LTE after CSFB call, seconds Figure 14.9 Example drive test measurement of ret