Wireless • Fixed wireless setup

How to set up fixed wireless internet for your business

A practical, vendor-neutral guide to getting a business-grade fixed wireless link installed, configured for voice, and hardened against outages – without the sales spin.

Last verified 1 July 2026
By the WhichVoIP editorial team
8 min read

Line of sightA clear path to the tower is the make-or-break requirement

5–15 daysTypical time to go live after the site survey

~100 kbpsPer concurrent VoIP call the link must carry

From ~R599/moEntry 5G fixed wireless; microwave runs far higher

The short answer

What do you need to set up fixed wireless internet for a business?

You need a clear line of sight to the provider’s tower, an outdoor radio (CPE) mounted high on your building, a PoE injector, and a business-grade router. A provider does a site survey first, then installs and aligns the antenna. Most sites go live in 5 to 15 business days.

Bandwidth per concurrent VoIP call the link must reserve

Typical upper bound to go live after a clean survey

Core hardware pieces: radio, mount, PoE, router

Independent links you want for true failover

Rooftop Fixed Wireless Antenna On A South African Business Building At Dusk, Aimed Toward A Distant Mast — Fixed wireless lives or dies on line of sight: the outdoor radio has to see the tower cleanly, which is why height and mounting position matter more than any spec sheet.

What fixed wireless actually is (and what it isn’t)

Fixed wireless delivers internet over licensed or unlicensed radio from a base station on a tower to a fixed antenna on your premises. It is not mobile data, and it is not fibre.

Because the receiver is fixed and aimed at a specific tower, fixed wireless can deliver low-latency, business-grade throughput that mobile LTE rarely matches consistently. The trade-off is physical: the radio needs a clear path to the tower. New buildings, growing trees and seasonal foliage can all break a link that worked on install day, so the mounting decision is a long-term one, not a convenience.

The path a fixed wireless connection takes

✓

Bottom line: if a provider quotes you a package without asking about your roof, your surroundings or a site survey, they are selling a price, not a connection.

The equipment you actually need

A business fixed wireless install is four core pieces plus two optional ones. The provider usually supplies and mounts the radio; the rest is worth owning and controlling yourself.

Provider-supplied

Outdoor radio (CPE)

JobReceives the tower signal
MountRoof or high pole
Owned byUsually the ISP

PoE injector

JobPowers the radio over the network cable
WhereIndoors, near the router
Back upPut it on the UPS

Business router

JobQoS, VLANs, firewall, failover
WhyConsumer boxes can’t prioritise voice
Owned byYou

The two optional pieces earn their place quickly: a UPS to keep the radio, injector and router alive through power interruptions, and a managed switch if you want to run separate VLANs for voice, data and CCTV. Mounting hardware (brackets, poles, weatherproofing) is part of the install, not an afterthought.

The site survey and installation, step by step

The survey is the single most valuable part of the process. It tells you whether the connection will work before anyone drills a hole.

Confirm coverage and book a surveyCheck the provider serves your address, then insist on a physical or drone-assisted line-of-sight survey before you sign.

Agree the mounting positionThe surveyor picks the spot with the cleanest path to the tower and the best signal margin, not just the easiest place to bolt a bracket.

Install and alignThe technician mounts the radio, runs shielded cable to the PoE injector, and aligns the antenna for the strongest, most stable signal reading.

Connect and testPlug the injector into your router, run a real throughput and latency test, and confirm the link holds under load, not just on an idle speed test.

Go live and documentRecord the signal readings at handover so you have a baseline to compare against if performance drifts later.

No clear line of sight? You are not automatically out of options. A relay point on a neighbouring building or a secondary mast can bridge an obstruction, but it adds cost and a second point of failure, so price it honestly.

Configuring the network so voice comes first

A fixed wireless link is fast enough for VoIP, cloud apps and video conferencing, but only if you stop those workloads from fighting each other for the same bandwidth.

Voice is unforgiving: it needs low latency and steady packet delivery, not raw speed. Budget roughly 100 kbps up and down per concurrent call using the standard G.711 codec, then configure the network so that voice always wins a contention fight.

Turn on QoSPrioritise SIP and RTP voice traffic on the router so a large file upload can’t starve a live call.

Isolate voice on a VLANA separate voice VLAN keeps CRM syncs, backups and CCTV off the same broadcast domain as your phones.

Monitor jitter and latencyWatch the metrics that actually predict call quality, not just the download number a speed test shows.

When you’re choosing	Fixed wireless	Fibre
Areas without fibre	Works where cables don’t reach	Only where the network is built
Speed to install	Days once line of sight is confirmed	Weeks if trenching is needed
Peak throughput	Strong, tower-dependent	Highest and most consistent
As a backup link	Ideal second path to fibre	Works, but same-medium risk

Fixed wireless doesn’t fail on the spec sheet. It fails on the roof – on the tree that grew, the building that went up, the mount nobody checked.

WhichVoIP editorial view

Technician On A Rooftop Aligning A Fixed Wireless Antenna Against A Clear South African Sky — Alignment is a craft: a few degrees off the tower can turn a strong link into an intermittent one, which is why the install technician’s signal reading at handover is worth recording.

Building in redundancy and security

A single link, however good, is a single point of failure. Business continuity comes from a second path and a hardened edge.

Pair the fixed wireless link with a genuinely independent second connection, ideally on a different medium such as LTE or fibre, so one outage doesn’t take voice and internet down together. Configure automatic failover on the router so the switch happens without a human noticing. On the security side, a business firewall, a VPN for remote sites and disciplined firmware updates matter far more than any single feature toggle.

✓

On power: put the radio, PoE injector and router on a UPS so a short power interruption doesn’t drop your voice and internet. It is the cheapest resilience upgrade you can make and it applies to every connection type, not just wireless.

Our verdict

Fixed wireless is a genuinely business-grade option where fibre isn’t available, and a smart backup where it is. The technology is proven; the risk is almost entirely in the site survey and the mount. Get the line of sight right, own your router, prioritise voice, and add a UPS plus a second link, and a fixed wireless connection will carry a serious workload.

Our recommendation: never sign before a physical line-of-sight survey, and treat the mounting position and a UPS as non-negotiable parts of the install, not upsells.

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Frequently asked questions

Does fixed wireless need line of sight?

In most cases yes. The outdoor radio needs a clear path to the provider’s tower. Where a direct path is blocked, a relay point on a nearby building or mast can sometimes bridge the gap, at extra cost.

How long does a fixed wireless installation take?

Once coverage and line of sight are confirmed by a survey, most business sites go live within 5 to 15 business days. The survey itself is what determines whether the link is viable at all.

Is fixed wireless good enough for a VoIP phone system?

Yes, provided you reserve bandwidth for voice and prioritise it. Budget around 100 kbps per concurrent call on the G.711 codec, enable QoS, and keep latency and jitter low.

What equipment do I need for business fixed wireless?

An outdoor radio (usually supplied by the provider), a PoE injector, mounting hardware and a business-grade router. A UPS and a managed switch are strongly recommended additions.

Can I use fixed wireless as a backup to fibre?

It is one of the best backup options because it uses a completely different medium from fibre. Configure automatic failover on your router so traffic switches over without manual intervention.

What does fixed wireless cost for a business in South Africa?

Entry 5G fixed wireless typically starts around R599 per month, WISP fixed wireless runs roughly R899 to R2,500, and licensed point-to-point microwave sits well above that. Always confirm current pricing with the provider.

Keep reading

Why fixed wireless works for SA businesses
Fixing common fixed wireless problems
Best wireless internet for business
VoIP speed and network requirements

Sources: ITU-T G.711 codec bandwidth reference; WhichVoIP South African wireless market pricing data; standard fixed wireless installation practice (line-of-sight survey, PoE-powered CPE, QoS and VLAN configuration). Verified 1 July 2026.