Shulou(Shulou.com)06/02 Report--

1. After UE is turned on, UE first needs to synchronize downlink through DwPTS, determine the boundary timing of subframe by SYNC DL, and then determine the boundary of multi-frame by phase modulation of SYNC DL. SYNC-Dl is involved, which corresponds one to one to the midamble code group of PCCPCH, while one midamble code corresponds to one scrambling code. After getting the downlink synchronization, you can decode the BCH and read the SIB message.

The question is: when does the frequency scan take place, and is the upstream synchronization after the downlink synchronization is established, and before the RRC Connection is established?

The first transmission of uplink synchronization is to obtain the timing through UL SYNC,NodeB by measuring it, and send the timing adjustment to UE,UE for application and adjust the transmission time. UE sends PRACH or E-RUCCH reply to NodeB,UL synchronization in the form of open-loop and closed-loop synchronization.

2. The measurement of L1 will be initiated only when the SW of L1 initiates a request to FW, mainly the RSSI of RSCP,timeslot of intra/inter frequency and the BSIC of RSSI,GSM of GSM.

The RSCP of intra-frequency is obtained by measuring the midamble of TS0 of working frequency. The RSCP of inter-frequency is obtained by measuring the midamble of primary frequency including serving cell. The measurement of RSCP is for cell reselection and to stimulate reporting to the network. In particular, the RSCP measurement of primary frequency is also used for time-frequency tracking.

ISCP is used to measure intra-frequency, which can be configured to a maximum of 5 DL slots, and serving cell and neighborcell can be measured.

Among them, the RSSI measurement can be intra-frequency or inter-frequency, which is obtained from the measurement of DwPTS, which is usually suitable for RSCP to carry out at the same time. Whether to carry out RSSI measurement is determined by FW. If no measurement is carried out, a null value needs to be returned.

The GSM RSSI measurement and BSIC measurement are carried out in the gap with idle time slots.

Two important concepts for the measurement process are scheduling point and scheduling interval. Where scheduling point is the place where UE initiates Gap Scheduling Function, and if HS-SCCH is configured in the TS6 slot, scheduling point is at the interruption of the last HS-SCCH of the i-th subframe. Otherwise, SW will set a cycle timer to trigger the scheduling algorithm. For scheduling interval, it starts with the TS0 of iTun1 subframe and the latter containing SCCH time slot, and ends with the busy time slot of iTun2 subframe or the TS before TS6.

Question: what are HS-SCCH and SCCH, and what is the difference? What does it matter?

3. Set up process of L1

Receive CCTrCH configuration and physical channel configuration parameters from L1 manager, authenticate configuration parameters, establish CCTrCH and PHY CHannel, calculate SF/RM parameters and encode them, and tell FW uplink DPCCH/PRACH configuration commands. Ask if L2 uplink data is available.

Question: what is CCTrCH?

4. Cell selection and reselection are completed through SIB3 and SIB11 messages sent by NodeB. After L1 completes the measurement, a CPHY_CELL_RESELECTION_IND and the scrambling code for the best neighbor cell,RRC will be sent to RRC and a command will be sent to L1 to switch to the new cell, if the new cell can be received.

5. UE determines whether UE executes BHO or HHO by including IE synchronization parameters. Among them, BHO first establishes the uplink communication of the new community, and then cuts off the downlink of the old community.

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