5G networks are here. US carriers are all moving ahead with their rollouts. Verizon currently has more than 10 cities turned up with go-live plans for 30 by the end of 2019. Early user testing shows promising yet mixed results. Watch WSJ’s Joanna Stern informative and entertaining review on the service.
Joanna’s video and accompanying article point out many technical challenges for carriers and handset manufacturers. I’ll focus here on the carrier side as it relates to millimeter-wave (24-40 GHz) base station deployment. The wide channel bandwidths at these frequencies are key to achieving the promised data rates of 5G. The challenge is that these frequencies are easily attenuated and blocked by almost everything we encounter in the real world: moisture, glass, brick, concrete, wood, foliage, and more, as Ms. Stern points out.
For decades US carriers have operated in frequencies that range from 600 MHz to 2.7 GHz. The propagation characteristics of these signals are well known, and in all but the toughest issues network quality of service can be managed remotely from a network operations center (NOC).
How well do the carriers understand millimeter wave? I think the answer is not all that well, as the current live tests of these deployments have shown. To grow these new networks to maturity, the carriers and their contractors are going to have to do extensive physical layer testing and evaluation of the frequency coverage on the ground. I don’t believe there’s any way around that.
For this type of work there are a variety of tools on the market that can be used for walk and drive physical layer testing. Some criteria for evaluation of this gear should include the functionality, size, form factor/weight, and cost; not necessarily in that order. The established players in this market offer fully featured toolsets that range from somewhat portable to quite uncomfortable and cost anywhere from $50k-$150k per toolset. This pricing isn’t unfair, considering the wide-ranging capabilities of these spectrum analyzers. Given the need for extensive physical layer testing, often requiring technicians to walk a sector, the form factor and cost of these toolsets is going to prove daunting. Much of the functionality found in these tools will rarely, if ever, be used. Many of these kits require an operator to wear a large, heavy backpack or chest harness. For extensive testing, this is quite a physical demand on the operator. In urban settings the setup can draw a lot of attention ranging from curiosity to outright concern from bystanders. Lastly, if each kit costs $75k, the cost to equip 30 network engineers is over $2M!
To address this specific problem, SAF Tehnika developed a smartphone-sized 24-40 GHz spectrum analyzer called Spectrum Compact. Spectrum Compact packs all the essential features needed to perform physical layer testing. The original concept was designed specifically for tower work, so a lightweight, comfortable form factor was a key design consideration. It powers up and is ready to measure in a matter of seconds. The analyzer works well in a variety of conditions, including extreme temperatures and rain. The onboard recording can retain hundreds of hours of data for post-processing analysis. The UI is intuitive and simple to learn. To top it all off, the tool and all the required accessories cost a fraction of what the other solutions do, enabling the carriers and their contractors to do more with their capital investment.
To learn more about Spectrum Compact visit: www.spectrumcompact.com
