How to Optimise Office Wi-Fi in Singapore High-Rise Buildings (DFS Radar, Concrete, and Why 2.4 GHz Is Unusable)
Last updated: October 2026
To fix office Wi-Fi in Singapore high-rise buildings, use 2.4 GHz only for devices that need it. Build capacity on non-DFS 5 GHz and 6 GHz. Plan more access points around concrete walls and lifts. Wi-Fi 7 does not fix an existing crowded or unstable band.
Megatron Technology designs Cisco Meraki and Cisco Wi-Fi for Singapore offices. This guide explains the three causes we see most and what to change.
Why is 2.4 GHz unusable for laptops in an office tower?
2.4 GHz has only three entirely non-overlapping channels: 1, 6 and 11. Every other office, phone hotspot and IoT device near you uses them. Your access points share airtime with all of them even if they are not physically in your office.
Keep 2.4 GHz for printers, scanners and IoT devices that cannot use 5 GHz. Turn it off on staff SSIDs where your laptop fleet allows it.
What is DFS radar, and why does it drop office Wi-Fi in Singapore high-rise floors?
Dynamic Frequency Selection (DFS) lets Wi-Fi use 5 GHz channels that radar also uses. Channels 52–144 are DFS channels. IMDA requires DFS on these channels. When an access point detects radar, it must leave the channel. Clients on that channel disconnect during DFS events, since the access point itself leaves the channel.
Channels 36–48 do not need DFS so you can use them first. Use 20 MHz or 40 MHz channel widths. One wide 80 MHz or 160 MHz DFS channel can take cause a floor-wide outage when DFS events are detected by the access point.
How do concrete, lifts and glass change the design?
| Building factor | Effect on design |
|---|---|
| Concrete core or lift lobby | Plan APs on both sides. One AP does not cover through the core. |
| Glass meeting rooms | Expect extra signal loss. Cover dense rooms directly. |
| Neighbour floors | Use lower transmit power, more APs and narrower channels. |
| Many 6 GHz clients | Use tighter AP spacing to get the 6 GHz benefit. |
| Frequent DFS events | Expect fewer usable 5 GHz channels. Use narrower widths. |
6 GHz cells are short. Do not remove APs because the new model is Wi-Fi 7.
Does Wi-Fi 7 MLO fix this?
No. Multi-Link Operation (MLO) lets a client use more than one band. In a high-rise, the 2.4 GHz link is noisy and the DFS link is unstable. The real gain comes from non-DFS 5 GHz plus 6 GHz. That gain needs 6 GHz clients and denser AP spacing. MLO does not replace a survey.
What should you send us for a survey?
A floor plan with the core, lifts and glass rooms marked.
A screenshot of neighbour networks from the Meraki dashboard (Air Marshal or RF spectrum).
Your client mix: how many laptops support 6 GHz.
Any devices that need 2.4 GHz.
Where can I read more?
Frequently asked questions
Why does my access point keep changing its 5 GHz channel?
It probably detected radar on a DFS channel. The rules require it to leave that channel. Use non-DFS channels 36–48 first and narrower channel widths.
Should we turn off 2.4 GHz in our office?
Turn it off on staff SSIDs if all laptops support 5 GHz to prevent issues where clients connect to 2.4 GHz channel with higher interference. Keep it for printers, scanners and IoT devices that need it, preferably on a separate SSID.
Will Wi-Fi 7 fix slow Wi-Fi in a high-rise office?
Not by itself. Wi-Fi 7 helps when 6 GHz clients exist and AP spacing suits 6 GHz. It does not remove radar events or 2.4 GHz congestion.
Should we use 80 MHz or 160 MHz to make wifi faster?
Usually not in a busy office. Without DFS, 5 GHz has only two clean 80 MHz channels and no 160 MHz channels. Overlap between APs then costs more speed than the wider channel gives. Enable DFS to get more wide channels, and check the dashboard for radar events. Use 20 or 40 MHz where you have many APs. Use 80 or 160 MHz mainly on 6 GHz, which has no DFS."
How can Megatron Technology help with your floor?
Send us the floor plan, a neighbour RF screenshot and your client mix. We size Cisco Wi-Fi for the bands that work on your floor. Reach out to us for a quote if you need a price. Contact us.
Megatron Technology (est. 1990, UEN 199002644W) is an authorised Cisco Networking Partner and Managed Services Provider in Singapore, and a Fortinet reseller. Our 4 Cisco-certified engineers design, licence, procure, deploy and support Cisco Meraki, FortiGate and Cisco enterprise networks. Verify us on the Cisco Partner Locator. Contact: +65 6346 2001 · info@megatron.com.sg.
Sources (checked October 2026):
Cisco Meraki: Dynamic Frequency Selection (DFS) (documentation.meraki.com)
IMDA Technical Specification for Short Range Devices (TS SRD) [VERIFY current issue]