logo

Are you need IT Support Engineer? Free Consultant

Unlocking wireless efficiency: How asymmetric bandwidth helps South Africa beat spectrum congestion

  • By Duxbury Networking
  • May 14, 2025
  • 774 Views

As South Africa continues its push toward greater digital inclusion and economic resilience, the demand for reliable broadband has never been more urgent. Yet, limited spectrum availability and rising levels of wireless interference, particularly in the 5 GHz band, make it increasingly difficult to meet this demand efficiently. This is where one of Cambium Networks’ latest innovations, asymmetric channel bandwidth in the ePMP 4000 Series, is changing the game.

Spectrum scarcity

In a country where fibre remains out of reach for many underserved and rural areas, wireless networks play a vital role in closing the digital divide. Wireless Internet Service Providers (WISPs), educational institutions, healthcare networks, and even industrial sites are all turning to fixed wireless as a practical solution. But in high-density environments or where multiple operators are sharing unlicensed spectrum, interference becomes a limiting factor.

Traditionally, fixed wireless access (FWA) systems use symmetric channel bandwidths meaning both uplink and downlink consume equal portions of the spectrum. While this works in many scenarios, it fails to account for the reality that most users download far more data than they upload. That inefficiency results in wasted spectrum and limits the number of users that can be served effectively.

What asymmetric bandwidth means

The ePMP 4000 Series from Cambium Networks introduces support for asymmetric channel bandwidth, a flexible feature that allows network operators to independently configure uplink and downlink bandwidths. For example, a 40 MHz channel can be allocated as 40 MHz for downlink and 20 MHz for uplink. This customisation allows for better spectrum use in high-traffic environments and tailored performance that matches real-world usage patterns.

Cambium’s solution does more than optimise throughput.  In many networks, APs on crowded high sites suffer from interference the most during their uplink phase. Using narrower uplink channels reduces the impact of uplink interference with the primary objective being to reduce uplink retransmissions. This in turn improves latency and jitter.

Relevance to South African use cases

This is especially relevant in South African townships, dense urban business parks, or rural deployments where several WISPs may operate in proximity. These areas often experience limited spectrum availability, and the regulatory environment for unlicensed bands is becoming increasingly complex. Asymmetric channel bandwidth offers a practical solution that does not require new infrastructure or additional spectrum allocation.

For WISPs serving high-demand residential zones or enterprise users, the ability to allocate more bandwidth to downlink-heavy applications like streaming and cloud services improves customer satisfaction and supports higher service-level agreements (SLAs). For mining operations or remote offices with IoT devices, prioritising uplink might be the better configuration. The point is: asymmetric bandwidth lets you choose.

We have seen first-hand how this capability has enabled more efficient deployments without adding cost. It provides our local integrators and ISP partners with the flexibility to maximise ROI on existing equipment and spectrum. In a market where rolling out new infrastructure is expensive and slow, innovations like these allow South African businesses to stay competitive.

Looking ahead

As South Africa expands its 4IR ambitions and broadband continues to underpin education, remote work, and digital government services, the way we manage spectrum will become a decisive factor. Cambium Networks’ ePMP 4000 Series with asymmetric channel bandwidth equips local providers with the tools to meet these challenges intelligently.

It is no longer just about more bandwidth; it is about smarter bandwidth. And in a spectrum-constrained market like ours, that makes all the difference.

To find out more about how Cambium’s innovations are enabling more with less, visit www.duxbury.co.za or call +27 (0) 11 351 9800.