gNodeB Capacity Calculator
Size a 5G gNodeB across its cells: air-interface capacity, N3 midhaul transport and supported connected devices.
Inputs
Site Air-Interface Capacity
5.40Gbps
Busy-Hour Offered Load
3.51Gbps
N3 Transport Required
4.14Gbps
Connected Devices Supported
7,200
Step by step
Values used
Cells on the site = 6 cells; Usable capacity per cell = 900 Mbps; Planned busy-hour load = 65 %; RRC-connected devices per cell = 1,200 devices; N3 encapsulation and security overhead = 18 %
gNodeB Capacity
site capacity = cells × per-cell capacity; N3 transport = site capacity × planned load × (1 + encapsulation overhead).
Site Air-Interface Capacity
= 5.40 Gbps
Busy-Hour Offered Load
= 3.51 Gbps
N3 Transport Required
= 4.14 Gbps
Connected Devices Supported
= 7,200
How it works
A 5G site aggregates several cells across bands and sectors, and its transport link only needs to carry the busy-hour offered load rather than the theoretical sum of every cell's peak. GTP-U encapsulation and IPsec then add a fixed percentage on top. Midhaul and backhaul upgrades have long lead times and civil-works costs, so the N3 figure — not the air-interface peak — is what belongs in the transport order.
Formula
gNodeB Capacity
site capacity = cells × per-cell capacity; N3 transport = site capacity × planned load × (1 + encapsulation overhead).
- planned load
- Busy-hour utilisation the design targets
- N3
- gNodeB-to-UPF user-plane interface
Frequently Asked Questions
How is gNodeB Capacity calculated?
site capacity = cells × per-cell capacity; N3 transport = site capacity × planned load × (1 + encapsulation overhead). A 5G site aggregates several cells across bands and sectors, and its transport link only needs to carry the busy-hour offered load rather than the theoretical sum of every cell's peak. GTP-U encapsulation and IPsec then add a fixed percentage on top.
Why does gNodeB Capacity matter?
Midhaul and backhaul upgrades have long lead times and civil-works costs, so the N3 figure — not the air-interface peak — is what belongs in the transport order.
What values do I need to enter?
This calculator takes 5 inputs: Cells on the site, Usable capacity per cell, Planned busy-hour load, RRC-connected devices per cell, N3 encapsulation and security overhead. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.