SIJ had the chance to catch up with Dr. Lee McMillan, Director of Engineering, Noisecom, about where he sees the company’s SI/PI portfolio going, and the upcoming opportunities and challenges of PAM4. McMillan is the director of engineering at Noisecom, a wholly-owned subsidiary of the Wireless Telecom Group. He has 20+ years industry experience and has worked for Noisecom for more than 17 of them. He studied his BE and PhD at the University of Queensland Australia.

Noisecom has been developing high frequency noise sources aimed at RF and microwave applications for many years.  At the highest level, engineers working in these applications have the same needs as digital designers, to add interference, noise and jitter, to their signals to test for real world performance. 

Fundamentally, a high speed digital design and a RF/microwave design are similar, the objective of both is to communicate a message at high speed with minimal error.  Several years ago we started to see inbound inquiries for high speed digital and serial data applications where engineers wanted to add noise or jitter, and our products for these applications were born. 

A noise source or programmable noise generator is a low cost alternative to AWG, VSG or BERT solutions used for interference signal generation and many digital designers have seen this as a good way to generate and add jitter to their signals.

SIJ: Do you have individual staff members that work in both application areas? If yes, how is that a benefit?

The Noisecom R&D and manufacturing teams have significant expertise in the development and manufacturing of noise sources.  We leverage what we have learned from decades of participating in the RF space to make better products and more robust solutions across all the customers we serve.  We charge our sales and marketing teams to look for a broad range of opportunities based on our core competency and use that to define what we do next and what applications we pursue.

SIJ: How do you foster innovation at Noisecom?

We strive to be customer driven and focused at Noisecom.  Our history is in unique products customized or modified for unique applications.  We leverage that history and the customer relationships built from that to identify the next areas of focus and investment.  Our engineers are directly connected to our customers and that one-on-one technical interaction is where our innovation comes from, directly from the trends and activities we see our customers involved in. 

SIJ: What are some of the most common questions you are getting from engineers grappling with SI/PI issues?

Many digital engineers that are considering an RF noise generator for the first time have a hard time visualizing how noise will work for them, how it can be injected in to their system or combined with their signal.  We typically try to show comparisons using the tools they are familiar with, like oscilloscopes and BERTs.  Questions then become centered on the characteristics of the noise signal and how it can be controlled or managed, such as what frequency bands or power levels are available, what are the inputs and outputs, what filtering or attenuation can be added, etc.  We find that our customers appreciate the high frequency expertise we have which gives them confidence in our ability to handle and support the demands of their application at their frequencies.

SIJ: How does test equipment need to evolve to satisfy the next wave of digital design challenges?

Test equipment needs to be simplified and become a lot easier to use.  The end user applications and the systems being developed and deployed are becoming incredibly complex as frequencies and data rates continue to increase while power consumption requirements decrease. 

Test equipment for these next generation designs needs to be simplified, allowing designers to focus on what matters most to them, understanding the performance and behavior of their products, not learning how to use the newest piece of test equipment in the lab.  Noisecom is focused on providing simple, low cost alternatives to expensive signal generators, signal analyzers or network analyzers and educating engineers on how noise can save time and money in both R&D and production test.  Any Noisecom product, from a basic module to a benchtop instrument is a simple device, power it up and connect to your circuit.

SIJ: Tell us about one of your latest products for SI/PI applications, how did it come about, what was the evolution, and what technical or market challenges had to be overcome?

One of our latest areas of focus has been using a noise source to verify the bandwidth of a test system before using it, specifically the bandwidth of an oscilloscope plus cables and interconnects, versus the stated bandwidth of just the oscilloscope. 

As digital engineers are dealing with higher data rates, they need to determine the frequency response and RF losses of interconnects in a system. System bandwidth of the oscilloscope plus cables can be verified using a noise source such as the NC1128B and the FFT function of the oscilloscope which gives a full system frequency response without needing to sweep signals and vary frequencies due to the broadband nature of the noise source. Once this data is collected it can be used for verification of all elements in the system and compared to future setups that may vary over time. 

This application came about by listening to trade show attendees ask us different questions about the characteristics of noise which got us thinking about noise differently.  We often see it as an interference signal used to stress test communication links, our customers and booth visitors got us thinking about noise sources as a broadband signal generator.  This has helped change our mindset and now has us looking for new opportunities where the broadband nature of noise can help validate, verify and quantify system performance, one example is in the setup of over-the-air measurements in the wireless space.

Have you seen a change in training needs from your customers? How do you satisfy their need for training?

There is a definite desire from customers to understand more about the product up front before doing an evaluation or before inviting a sales or application engineer in to their lab.  Their time constraints and the “has to be done now attitude” has led us to more online type sales and support calls, taking advantage of online meeting and screen share tools.  We feel we can address almost all training and technical support issues this way and it lets us deploy our resources better while taking up less of our customer’s valuable time.

SIJ: Tell us about how you engage with technical partners and how that process benefits your designs?

Our expertise is in noise generation and system integration.  At the most basic level, our products start as a diode that we build up in to a module and eventually a benchtop instrument.  Developing those instruments is what puts us in the realm of system integration as we need to incorporate programmable switches, filters, attenuators and even power meters and spectrum analyzers inside our products, all produced by third parties and design partners. 

In these cases, we rely on experts in other areas that can help us identify and integrate the right components for our applications.  At this point, we have some “go-to” partners that know our typical requirements and expectations, we can supply block diagrams and specifications and get back a range of components that our partner think will best fit our needs.  Through this process we have built some trusted partners who help us fine-tune and enhance our offerings by leveraging their individual areas of expertise.

SIJ: Can you share your product roadmap for SI/PI related products?

We continue to see new opportunities for noise sources and generators outside our traditional customers and applications.  We expect the next generation of emerging standards that use PAM4 to be an area of interest, focus and investment for us.  In signal integrity applications, our products are mostly used to add jitter to a signal. In the RF and microwave world, noise sources are seen as a way to add vertical interference. 

We see PAM4 as a meeting of these two mindsets as engineers look to pack more information vertically in their channels which can result in some requirements to measure noise tolerance that a noise source can uniquely address.  We have heard a lot about PAM4 over the past several years at trade shows and in magazines but with new standards finally embracing it we see some major industry players talking about how noise can be used as we transition from NRZ to four discrete levels with signal-to-noise as a major testing requirement.