LTE Handover Decisions
In cellular networks, handover decisions refer to the process of transferring an ongoing call or data session from one base station (cell) to another as a mobile device moves within the network coverage. This ensures uninterrupted service and maintains the quality of the connection. Handover decisions in 4G networks are typically made based on various factors and algorithms, including:
- Coverage Based Handover (HO): In this type of handover, the decision to initiate a handover is primarily based on the coverage area of the serving and neighboring base stations. If the signal strength or quality of the serving base station drops below a certain threshold and a neighboring base station provides better coverage, the handover is triggered to ensure continuous connectivity.
- UE (User Equipment) TX Power Based Handover: In this type of handover, the decision is based on the transmit power level of the user equipment (mobile device). If the mobile device’s transmit power exceeds a certain threshold, indicating a strong signal, a handover may be initiated to a neighboring base station that can accommodate the device’s power level more efficiently.
- Load Based Handover: Load-based handover decisions consider the current load or congestion level of base stations. If a serving base station becomes heavily congested, while neighboring base stations have lighter loads, a handover decision can be made to balance the network traffic and distribute the load more evenly across the cells.
- Service Based Handover: Service-based handover decisions take into account the type of service or application being used by the user. Different services may have specific quality of service (QoS) requirements, such as low latency or high bandwidth. If the serving base station cannot meet the required QoS for a particular service, a handover may be initiated to a base station that can provide the necessary QoS.
- Priority Based Handover: Priority-based handover involves assigning priorities to different user equipment or services. Users or services with higher priority receive preferential treatment during handover decisions. For example, emergency calls or critical services may have higher priority over regular voice or data sessions, ensuring their seamless connectivity even in congested network conditions.
These different types of handover mechanisms help optimize network performance, maintain service quality, and ensure efficient resource allocation in cellular networks. The specific algorithms and parameters used for handover decisions may vary depending on the network technology and implementation.