My oscilloscope wish-list doesn't settle for blind spots or tunnel vision
2020-05-11 | 11 min read
Working late at my test bench on an elusive hardware problem, I envisioned a less frustrating workflow. A clear distinction emerged between the productive steps I was taking, versus the time-consuming workarounds I had to conjure up because my bench oscilloscope wasn’t up to the task. So, I thought…
Wish #1: I want the capability to see important signals that I can’t see now. Like any tool, test equipment is not inherently good or bad. My DVM is great for measuring voltage but is useless for measuring rainfall. Likewise, my old 2 GHz oscilloscope is great for seeing some signals but leaves me completely blind when I troubleshoot a 5GHz Wi-Fi 6 router. That’s capability, but now let’s talk about capacity…
Wish #2: I want the capacity to see more of those signals at the same time. Relationships between signals are critical when I need to find the root cause of a problem. Looking at one channel at a time is like seeing the world from inside of a tunnel. Everything that affects that singular view is missing. For my oscilloscope, finding the context of the signal I am focused on translates into channels. The more channels I have, the more context I get. That’s capacity, but more isn’t always better…
Wish #3: I want the flexibility to have it my way, even if I change my mind later. One size doesn’t fit all. I know what I need, and more bandwidth and more channels aren’t a panacea. I need the right bandwidth for my products, and I need enough channels to be able to apply my experience to look everywhere I know problems might be found. I’ve got a job to do and I need the right tool for that job. What I want when selecting that tool is a solid menu to choose from, simply written in the language of what I need my oscilloscope to do. If my needs change in the future, I want an upgrade path.
Oscilloscope genie - do your stuff. Capability, capacity, and flexibility. Help me banish my bandwidth blind spots, eliminate my channel tunnel vision, and give me meaningful options.
The right capability for the job – There’s a lot going on between 2 GHz and 6 GHz
My 2 GHz scope has been a reliable workhorse over the years, but the growth of new technologies and applications operating between 2 GHz and 6 GHz is astounding. I hate to retire my old scope, but I have important product families coming up that will need that higher bandwidth.
Wi-Fi 6: Wi-Fi carries more internet traffic today than any other wireless technology. Current 2.4 GHz (b/g) and 5 GHz (n/ac) Wi-Fi dominate today’s products and services, and as a result, are increasingly congested. The next-generation Wi-Fi 6, also known as IEEE 802.11 AX operates within the 5 GHz band, but with many significant performance improvements.
Wi-Fi 6 uses orthogonal frequency division multiple access (OFDMA) in combination with multi-user multiple in, multiple out (MU-MIMO) technology, resulting in a disruptor over earlier Wi-Fi standards because it allows multiple users to transmit simultaneously and asynchronously.
Why is Wi-Fi 6 important from an end-user’s perspective? Improved beamforming that virtually eliminates dead zones. Four times better throughput in dense environments, 40% higher peak data rates, four times greater network efficiency, and a dramatic improvement in client device battery life. This is going to be a market disrupter and one of my jobs will be to troubleshoot power integrity issues in a whole new generation of Wi-Fi 6 devices. It all happens in the critical spectrum between 2 GHz and 6 GHz.
IoT: Wi-Fi 6 allows for higher densities of devices, opening the door to many more users per node than previous generation sharing ever could. The resulting applications for the industrial and consumer internet of things bring countless new opportunities. 5G expands Wi-Fi 6 farther afield. Time-domain testing needs for the 5G FR1 band integrated with Wi-Fi 6 demand the 2 GHz to 6 GHz spectrum.
Imaging: Synthetic aperture radar (SAR) operating between 100MHz and 6 GHz creates three-dimensional reconstructions of objects with numerous space-based, terrestrial, and medical imaging applications. Applications exist in both primary and secondary testing.
Primary product testing in the development of SAR technologies improves both the time to market and the quality of images. The next generation of smaller tip SAR field probes operating between 2 GHz and 6 GHz dramatically reduce undesirable probe boundary effects closest to the phantom surface. Troubleshooting will be focused in time domain analog. Secondary testing requirements up to 6 GHz for SAR center around exposure reporting per IEEE Std 1528-2013 and FCC compliance.
Semiconductors: Sub 6 GHz massive MIMO will solve many of today’s signal interference problems by using many antennas at the base station. The resulting requirement for much higher power output and higher frequencies will increasingly put gallium nitride (GaN) semiconductor technology into play. That will require not just a broad 6 GHz bandwidth, but also the ability to probe in more and tighter spaces.
The right capacity for the job – See it all with 8 analog and 16 digital channels
Simultaneously monitoring eight analog channels and up to 16 dedicated digital signal paths on high speed digital, imaging, and semiconductor products is critical. In bench testing, time is of the essence. Having the right bandwidth viewed across more channels moves me from symptom to root cause to resolution fast.
Of course, it’s both a digital and an analog world, so when I’m chasing a complex mixed-signal design issue, I need to see both at the same time. My old scope required me to sacrifice analog channels to get enough digital channels. The oscilloscope genie would never be satisfied with that tradeoff.
The right flexibility for the job – Everything that I need, and nothing that I don’t
Cookie-cutter configurations are not good enough when it comes to bench test. My industry is different than others, and even within my industry, test needs are incredibly diverse. There’s an old saying, “I know what I know, I know what I don’t know, but I worry most about what I don’t know that I don’t know.” Investing in sophisticated test equipment in a rapidly changing technical world brings that saying to mind.
What I need in flexibility starts with a meaningful configuration menu to choose from today. Beyond high-performance hardware, it must include my industry-specific applications to automate predictable tasks. It must allow me to use the equipment within my real-world workflow, including the reality of needing to collaborate seamlessly across worldwide teams.
Here’s the menu I want - configurable memory, integrated toolsets, useful application suites, optional bandwidths, selectable numbers of channels, and choices in warrantees.
But let’s go back to what I don’t know that I don’t know. Every single one of those menu items must be upgradable later in my lab with no shipping of the scope. Is that too much to ask for?
Summary: More capability, more capacity, and more flexibility
No, it’s not too much to ask for. An eight-channel, 6 GHz fully customizable, and upgradable scope is here. Even better, the oscilloscope genie threw in some extra wishes that I didn’t even request. The Infiniium MXR-Series Real-Time Oscilloscope includes a built-in high powered eight in one set of bench instruments and a revolutionary ability to seamlessly use the scope for remote collaboration with my worldwide team.
Until now, eight-channel oscilloscopes hadn’t broken through the 2 GHz barrier, and some required analog channel tradeoffs just to get 16 simultaneous digital channels. As I look at justifying my next important capital investment to accelerate bench testing, I know that bandwidths are not shrinking, they are growing. The number of high-frequency channels and signals that I need to view, along with the complexity of their signal paths is not shrinking, it is growing. I can foresee both of those and for everything else that is yet unknown, I can count on a clear and flexible upgrade path.
Why would I settle for anything less?