How does a 5G connection remain active when a user travels from Delhi to Gurgaon?
This animation follows a person travelling by car along a simplified Delhi–NH-48–Gurgaon route.
As the car moves, the signal from the original serving cell becomes weaker. At the same time, signals from neighbouring cells become stronger.
The network must decide when to move the active connection to a better cell. This process is called handover.
The journey begins in Delhi:
5G Phone → Delhi Cell A
At this point, Cell A provides the strongest radio signal and acts as the serving cell.
As the car moves away from Delhi, the phone continues measuring signals from the serving cell and nearby cells.
A simplified 5G handover process includes:
1. Measurement
The phone measures radio conditions such as serving-cell and neighbouring-cell signal quality.
These measurements can include values such as RSRP, RSRQ, and SINR.
2. Measurement report
When configured conditions are satisfied, the phone sends a measurement report to the serving gNB.
For example, a neighbouring cell may become sufficiently stronger than the current serving cell for a configured period.
3. Handover preparation
The serving gNB selects a suitable target cell and coordinates the handover.
The target cell prepares radio resources for the arriving user.
4. Handover execution
The phone receives instructions to access the target cell.
It synchronizes with the new cell and completes the required radio procedures.
5. Handover completion
The target cell becomes the new serving cell.
User-plane traffic is redirected, old resources are released, and the session continues through the new radio path.
In this scenario, the serving-cell sequence is:
Delhi Cell A → NH-48 Corridor Cell B → Gurgaon Cell C
During the journey:
• Cell A signal gradually decreases
• Cell B becomes stronger along the corridor
• The first handover moves the connection from Cell A to Cell B
• Cell C becomes stronger near Gurgaon
• The second handover moves the connection from Cell B to Cell C
A successful handover helps maintain service continuity for applications such as voice calls, video streaming, navigation, messaging, and connected-vehicle services.
However, handover performance depends on many factors:
• Vehicle speed
• Cell coverage and overlap
• Signal strength and interference
• Handover thresholds and timers
• Network congestion
• Target-cell capacity
• Transport-network delay
• Radio-link quality
• Handover preparation time
If handover happens too early, the phone may move to a weaker target cell.
If it happens too late, radio quality may deteriorate and the connection may experience interruption or failure.
LinkedIn: 