February 1, 2021

Looking for a low cost way to grow your capacity?

For the last 30 years or more, communication networks have relied heavily on microwave technologies operating in traditional microwave bands (between 6 and 38 GHz) to provide fast, reliable, and cost-effective connectivity as an alternative to more expensive or bandwidth-limited wired alternatives (copper or fiber). With the broad rollout of advanced 4G technologies, the introduction of 5G underway, and as more people work from home and look for more flexible ways of doing business, the resulting demand for higher network capacities is competing with the congestion in these once reliable microwave bands. This congestion will inhibit the operator’s ability to extend their networks to connect new customers and deliver high bandwidth broadband services to rural communities.

Scaling up Microwave Link Capacity

Microwave links use available spectrum in specific chunks called channels—the wider the channel, the more capacity that can be supported. The usual ways of increasing capacity in a single channel, such as higher modulation, using both polarizations with XPIC, and payload optimization techniques, have reached the point where the capacity improvements are a matter of diminishing returns. New high-frequency bands with much larger channel bandwidths, such as the 80 GHz E-Band, cannot support the link distances needed with sufficient reliability to be a complete solution.

Significant Upgrade Cost and Complexity

For the past number of years, operators have been stacking multiple channels, meaning multiple radios, to support higher link capacities. This approach is effective but is costly and ultimately does not scale. A typical single channel in a traditional ETSI band can support up to 500 Mbps and 730 Mbps for FCC. Doubling the link capacity to 1 Gbps involves doubling the amount of equipment needed, and hence your investment. Four times the capacity, or 2 Gbps, would mean 4x the investment. And it is not just the cost of the additional equipment as capacity needs grow. Each upgrade will also require additional recurring expenses for new microwave spectrum licenses and the costs to procure, ship, install and configure the additional radios. To climb a tower to add new radios can cost more than the new equipment itself.

Getting Higher Capacities is Increasingly Difficult with Microwave

Combining more than four microwave channels on a single antenna gets complicated and expensive, meaning that the practical and economical microwave link capacities run out of gas at around 2 Gbps (for 4x 56 MHz ETSI channels), 3 Gbps (for 4x 80 MHz FCC channels), or in the rare event that you can license 112 MHz ESTI channels, up to 4 Gbps. Beyond that, the next alternative is probably fiber, which comes with different economic and deployment challenges.

Multi-Band – Incremental Up-Front Investment for near Unlimited Capacity

In contrast, Aviat’s unique Multi-Band solution enables smooth capacity migration up to 10 Gbps, without additional hardware investments, no site visits or tower climbs, and (in most cases) little or no increase in spectrum fees. Capacity increases are as simple as you can get – order through Aviat Store and then download your capacity upgrades from AviatCloud.

Higher Capacities with much Lower TCO – what’s not to like?

Multi-Band does require some foresight as to your future capacity needs and a small premium up-front investment compared to deploying a microwave link. Still, then you have almost unlimited capacity at your fingertips. Since most networks have as much as 70 to 80% of links below 10 km (6.21 mi) in length, they are ideal candidates for Multi-Band deployment (depending on rain region and path design). You can consider Multi-Band as a viable alternative to deploying any new link in traditional bands. Depending on the spectrum fees charged in your country, Multi-Band can also lead to significant savings in fees where E-Band is charged at a much lower rate per Gbps of capacity.