What are the functionality of eNodeB?

E-UTRAN consists solely of the evolved Node B (eNB), which is responsible for all radio interface functionality.

eNB is the RAN node in the EPS architecture that is responsible for radio transmission to and reception from UEs in one or more cells.
The eNB is connected to EPC nodes by means of an S1 interface.The eNB is also connected to its neighbor eNBs by means of the
X2 interface. Some significant changes have been made to the eNB functional allocation compared to UTRAN. Most Rel-6 RNC
functionality has been moved to the E-UTRAN eNB. Below follows a description of the functionality provided by eNB.

Good PDF Document on LTE Functionality

UMTS/HSPA to LTE Migration

UMTS/HSPA to LTE Migration- A white Paper from Motorola Maximize the life and value of existing assets while achieving a true 4G network

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Contents
Abstract
- A Dynamic Industry and Technology Evolution
- LTE Performance
- UMTS " LTE Network Architecture Evolution
- Determine the Business Case for LTE
- Subscriber Device Availability
- Deployment Considerations
- Seamlessly Connected Network
- Spectrum Implications
- Maximize Existing Assets
- UMTS to LTE Upgrade Strategy
- UMTS/LTE Architecture
- Functional Elements
- UMTS / HSPA RAN Site Upgrade to LTE
- Backhaul Site Upgrade to LTE
- LTE Voice
- LTE Video

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