Following are the some basic and advanced Top LTE Advanced Interview Question and answer for both beginner and experience LTE Tester.
Before going ahead, please have a look on LTE Testing to have some better understanding on the LTE basic. Let’s have a look on LTE Advanced Interview Question
1. What are the two different ECM States ?
Ans. ECM Idle and ECM Connected
2. What are two bearers are required to access the IMS network and offer services in the LTE network?
QCI-5: Default EPS bearer to access IMS signalling
QCI-1: Dedicated EPS bearer for VoLTE VOIP traffic
3. Name channels used between RLC and MAC, MAC and PHY?
- RLC and MAC -> Logical Channel
- MAC and PHY -> Transport channel
4. List the procedure during which Non-contention-based Procedure used?
Ans. This procedure is used in case of handover of a UE from one eNB to another in order to reduce the handover latency.
5. What is the difference between S5 and S8 SGW interface ?
Ans. This is interface between the S-GW and P-GW. S5 is used for same interface and S8 is used when roaming between different operator.
6. List the 3GPP specification numbers after 36 for the following protocols?
Ans. 3GPP specification numbers after 36 for the following protocols are
- RRC – 36.331
- S1AP – 36.413
- X2AP – 36.423
- RLC – 36.322
- MAC – 36.321
7. List any four functionalities of EMM?
Ans. Functionalities of EMM are
- Service request
- Tracking area update
8. List any four functionalities of MME?
Ans. Functionalities of MME are
- Responsible for NAS signaling
- Handles mobility management in idle mode
- Bearer Management for UE
- Maintain UE context when UE is in idle state.
9. List any e-NB functionalities?
Ans. Functionalities of e-NB are
- Scheduling / Dynamic allocation of resources to UE
- State transmission from idle to connected mode
- Buffering of data during handover
- Controlling mobility of UE in connected mode
10. What is QCI? How many QCI exist in LTE as per 3GPP?
QCI = QoS class identifier. QCI used to identify the required access for user e.g. IMS, Voice call. As per 3GPP there are 9 QCI exist.