In this episode, our guest is Professor Hongwei Zhang from the Department of Electrical and Computer Engineering (ECpE) at Iowa State University (ISU). Here, we talk about his research in rural broadband connectivity and wireless communication systems, along with education-related topics for students. We also discuss his major new grant, ARA Wireless Living Lab for Smart and Connected Rural Communities, which was established under his leadership and has received around $16 million in funding from the National Science Foundation (NSF), United States Department of Agriculture (USDA), and several industry consortium partners. This episode was conceptualized, recorded, edited, and produced by Santosh Pandey from the ECpE Department of Iowa State University. The communications and digital hosting was handled by Kristin Clague from the ISU ECpE Department. The music was provided by beetpro from Pixabay (Track Title: Follow your destiny lofi chillhop 5).
Welcome to our ECpE podcast series where we talk about exciting activities within our department. I'm your host Santosh Pandey. Our guest today is Professor Hongwei Zhang from the Department of Electrical and Computer Engineering (ECpE) at Iowa State University. Hongwei, thank you for joining our listeners today. Today, we want to chat about your research on wireless communication systems and rural broadband, along with education-related topics that will benefit our student listener. To start with, wireless communication networks are essential in our effectively address the 21st century challenges - be it in extended reality, connected and automated vehicles, smart and precision agriculture, smart energy grids, industrial IoT, or cyber physical systems. Do you think we are too dependent on wireless networks today? Yeah, that's a great question, Santosh. You know, in many ways, computer networks, such as wireless networks, have become, to some extent, essential utilities for all of us, right? Just like water and electricity. But on the other hand, there's just so many sources of uncertainties and so on in wireless systems, right? So the question is how can we develop wireless networks we can bet our life on, right, so that we can really depend on them no matter what. I think that it's actually an open question today. I think there's benefit of wireless networks are there, It's even essential for many industries, also even our daily life. Just imagine how much time we use our cell phone. So looking forward, there's this really core question of how do develop trustworthy, dependable wireless networks that can serve us the foundation of 21st century communities and industries. There are actually many research questions to be answered, a lot of opportunity for our students, our faculty members, and the industry to work actually to hopefully deliver this, the level of dependency that's needed for such mission critical networks. Could. You briefly describe some of your research work here at Iowa state and what facilities are available in your research laboratory to support your work? My own research has been mostly focused on, you know, in layman's language - how do we develop wireless systems that we can bet our lives on. Essentially we look at the kind of wireless networks that tend to be, you know, mission critical or even safety critical, such as some of the use cases you mentioned earlier - agriculture, autonomous transportation and so on. So one of the specific questions we have been looking at is how can we enable predictable, real-time wireless communication for those safety critical cyber physical systems. So that's kind of, you know, in a nutshell our general research direction. Now in terms of research facilities that are available at ISU to support this kind of research and other wireless research, we have been developing different types of facilities. For example, in our department building, in Coover 3038, we have kind of indoor test bed of software defined radios, plus some IOT devices. We have recently completed another field project, the CyNet project by which we have deployed open source 5G type of base stations at the ISU Curtis Research Farm and ISU Research Park in the south part of the town. And then there's actually another very exciting project we started about half a year ago, in collaboration with many colleagues in our Ahmed, Mai, Yong and many other colleagues in our department, Tom and so. And together with other colleagues in the university and partners in State of Iowa and beyond. We are building this ARA Wireless Living Lab which we hope will serve, you know, first of its kind research infrastructure for allowing us to study the next generation of rural broadband solutions. And part of that is gonna be focused on the safety, critical mission, critical wireless systems which I personally actually time on today. And, you know, as part of the living lab effort, we would also be working on activities, processes, and that can help engage our students, our partners in industry and communities, also the broader research community to work on some of the grand challenges we kinda alluded to, right? How do we enable trustworthy, dependable wireless systems for safety critical applications? So, you know, the project is actually just started, but we look forward to working with our students and partners in the coming years to really push the boundaries of wireless systems in general. So. That's great. What are your thoughts on the broadband divide that exists in rural America today, in that, people living in cities have access to the fastest internet while those in rural areas have 20 megabits or, or less of internet. Speed? So it's unfortunately to see the broadband divide we have today. You know, in USA, we have tens of millions of people living the rural Americas. And also if you look at the rural industry such as agriculture, the future of agriculture is actually dependent on having broadband connectivity to the field, right to the, farms, which we don't have today. So there are actually many reasons for the situation we have today. One of them is because there's a lack of focus to develop rural specific technologies. Most of the broadband technologies are developed , you know, in San Diego or Silicon Valley, you know, and in other technology centers in the country or across the world, right? So most often when a new generation of solutions emerge, then they tend to focus where the majority of the use cases are, right, which tend to be, unfortunately, if you look at the number of users will be actually on urban settings. So that's why we kind of see that most of the technologies that are available today are mostly developed with the specific urban use cases and settings in mind. That's part of the reason we don't have, for example, the technologies that are affordable enough to be So in order to address those root causes, essentially we have to look at the specific rural even including the rural economics and how that impact the type of technology that would succeed in the rural regions. Those are some of the motivations for us to start actually looking at the rural broadband as a research direction and see how that may actually help address the challenges we see today. I guess, you know, one thing we have learned in this exploration so far is that, yes, there are those challenges that we need to address. But in the meantime, it turns out those challenges are actually really, really good opportunities for us to think about rural-focussed innovation and community development. You know, I feel that there are actually many forces that are coming together to allow us to start think about the future where you could see, you know, kids in the rural community start becoming the drivers of some of the rural focused technology innovation. And as such, innovation could become a foundation for community and economic development. I think that those are some of the topics beyond what we would tend to focus on as engineering professors, but I think there's just so much opportunity over there for our students and faculty members to start thinking about and help potentially leverage some of those opportunity is to create exciting path forward for the rural communities and even for our students and kids in Iowa. Right, right. You know, if you see the field of agriculture or livestock farming, it is challenging to have a sustainable and profitable business for farmers, for example. On the other hand, wireless communication and wireless network - they are driven by cost and profitability. So whereas in agriculture and livestock farming, profitability is very challenging because it's complicated and there are a number of issues and constraints that limit profitability. So in that space, is it practical to incur the extra cost of setting up wireless communication networks? Or do you think in the long run, farmers can actually generate profit? Yeah. Yeah. Great question. Santosh. There have been studies by USDA and many other researchers and research organizations. One number I actually remember was something like the following. So if you have broadband serviced to the farm in USA as a country, the enabled precision agriculture can generate up to over 40 billions of new revenue, just because of the use of broadband-enabled precision So yes, there's actually the cost of rolling out the broadband technology itself or service itself. But along with that, it actually creates the opportunity for improving the efficiency of agriculture, for example, for reducing the input such as water and fertilizer, but also maximizing the output, right, as a way of actually improving the profitability of Do you think your recent project on ARA Wireless Living Network can address the broadband divide that we just talked about? I think, you know, the ARA Living Lab could be a facility, could be a tool, for the broader communities to address the broadband divide. You know, addressing the broadband divide would actually really take a whole industry or whole community approach. But what we can help, I think at ISU would be - one, establish the living lab facility well, and then also be a good contributor in terms of research, education, innovation, for example, help our students succeed. Right. They could be the driver of some of the new technology innovation. And so we are here to help. Yeah. So I would imagine that we could be a contributor, even though we will not be alone, will not be able to adjust the divide by ourselves. You know, wireless networks need to be highly predictable and reliable, and there needs to be less uncertainties and there needs to be higher throughput. Isn't all of this too much to ask from real world systems. And what are some of the biggest hurdles in realizing predictable and reliable wireless networks, especially in the 5G generation? Yeah, that's a great question. You know, compared to wired networks, there are just so many sources of uncertainties and dynamics in the wireless networks, right? For example, if you just look at the wireless channel, given two radios, one transmitter and one receiver, you know, depending on whether there's actually some movement in the environment, the channel is gonna be different. There are those very inherent dynamics uncertainties that you may not see in the wired network systems. And with the openness of wireless signals, it's also just opens up the door for attack. There's actually just a lot more attack service when it comes to wireless networks. But that said, I think, you know, just like when we think about internet, right, uh, when internet started by in the 1960 line, the first message was sent to three letters. You know, it was from the UCLA to Stanford Research Institute (SRI). The researchers leading the project at the time were trying to send a word like "LOG IN", right. L O G I N. They wanna log in to from UCLA to the machine in SRI, but then the network was just not reliable, right. Even though it was wired, only three letters were able to get through - LOG. That was 1969. But if you look at today, now look at the wired internet, you know, once in a while, it may still fail, fail miserably. But, you know, I say, you know, 99% of the time, the wired internet has been able to serve its purpose. So I guess intellectually the question is how do we build dependable systems out of independable components? I think similar question may have been asked in various disciplines in computing. I would imagine probably in your field, which I don't understand as much Santosh, but would love to. I think the beauty of the question is really how do you build dependable, trustworthy systems out of unreliable components. Especially in rural areas where you are exposed to environmental changes, weather changes and, everything else. Right, right, right. So, especially for our students who may have been looking at coding theory, one interesting exercise we just recently started actually was look at, by working with Mike Luby, one of the founder or the pioneer of Fountain Code. We are looking at the case where - Can you have a strategy such that if you look at the end user experience, the message would flow across the network and adapt to the network condition in a seamless fashion. So there are certain strategies that can be leveraged to address some of this inherent, like for example, weather impact that, you know, we will be actually starting to look at. We would very much welcome participation for our students in some of these project explorations. I presume these days, most of the innovation and wireless communication systems is led by industry. Could you talk about your industry partnerships and what do you think is the role of academia in furthering innovation in this area? You know, working with industry has been always a source of inspiration for myself. Actually, we get to what are the challenges they face and also the constraint they have to keep in mind when coming up with solutions. You know, in academia, we can simplify our assumptions and relax our constraint and so on, but it's not for the real world. So, it's a continuous learning process for the ARAproject. We actually have partners from actually various industries. You know, we have partners from the wireless industry, We have partners from the application technology industry, for example, the Collins Aerospace who's using wireless for, for example, for drone control, for extended reality. We also have partners in, what I would call, the application industry, such as agriculture, such as, you know, John Deere. And so on. Through the ARA Living Lab, we're trying to bring together the leaders in the broad ecosystem that's needed to drive the development of wireless technologies, as well as their use in specific industries, applications. Besides working with existing industry leaders, there are opportunities for startups, I do believe in this space. For example, ISU has recently started this Student Innovation Center. We have many other innovation focused training programs across campus. I think our students can actually leverage those opportunities, both entrepreneurship training, and also some of the research and innovation opportunities and application, I think help shape the future of the industry, because I think, you know, the only thing that do not change is change, right? The industry is changing. I think there's, um, need for new sorts and new approaches. That's where I think in general, USA has been doing very well in terms of empowering the startup communities. What we can do better, I think in the Midwest, is I think probably here in ISU is try to see how we can better help our students also to succeed in that space. Right. Instead of just thinking - when I graduate, I'm going to find a big company and then spend my life there. Right. But think about what are the grand challenges - grand addressed there and how can I really help solve those problems? And as part of that, you get a chance to actually do things that potentially even more exciting than joining a big company and then, you know, spending your career there. Yes. That's correct. When you started thinking about the rural broadband connectivity, there are so many options to choose from. There is the Leo satellite communication. There is WiFi, Bluetooth, Zigbee, LoRa. So how did you narrow down to one of these? That's actually a very good question. In fact, when we think about the use case of rural broadband, it's actually very diverse. It turns out there's no single technology that's gonna be the optimal solution for all use cases. So I think in the end, what's gonna happen is that you will see a combination of technologies, you mentioned, that will get used in general. For example, you could imagine a truly remote farm, right? A remote large agricultural farm with thousands of acres of land, and no people living there, actually. So you could imagine in that case, maybe the Leo satellite communication can provide a back haul, but once, so when you need connectivity in the farm, uh, you could potentially see maybe a portable 5G base station deployed at the field that's providing connectivity from the back haul to the, for example, agriculture machines on the farm. And then, you know, inside the vehicle, you can imagine potential of WiFi or Bluetooth for various in-cabin operations, right. And also as the vehicle drives around, it may communicate with sensors on the ground or on farm using ZigBee and so on. So I think it's gonna be actually a combination of different technologies. So one of the, I guess, research engineering question here could be, you know, how do we manage such complexity and ensure that the system can be analyzed, so that you can ensure predictability and dependability as we discussed before? Yeah. So again, this is actually a very interesting, another interesting dimension when it comes to rural broadband as a field. So what you're saying, or what I understand is the smartest way is to use a combination of different approaches in the field and see which ones work and which ones is best for the scenario, right? Yes. On a related question compared to wifi, for example, TV white space is said to be better suited for rural broadband connectivity, mainly because it can pass through obstacles, man-made or natural. Is that true? And what are the benefits over rivals? And a follow up question is, do you think TV white space holds the answers to all the rural broadband connectivity issues? Yeah. TV wide space is, uh, in a way to some it's actually a overloaded term. There was a time when this has been a very exciting research field. In terms of wireless spectrum, it refers to the low band spectrum, somewhere around the like 500 megahertz to 700 megahertz band. So being at the lower band, it does actually suffer less of the power attenuation -very convincing at the time. As I said, I think TV white space as a spectrum brand is still a prime band for rural broadband solution. It was part of the ARA project. We have some research platforms we plan to deploy that will leverage the TV white space brand. We will introduce some new technologies such as MIMO, the multi antenna solution to address some of the drawbacks of the, you know, previous generation TV White space technologies, for example, a lack of capacity, lack of coverage and some. So I think it's still a very spectrum band of huge potential. We should definitely try to find ways to leverage this resource. So could you describe some of your projects in open that's developed in your research and are you proponent of open source software? Yes, absolutely. I'm a proponent of open source in general. So in terms of open source hardware and software, we have been using some of the, like the software-defined radios from National Instruments, NI. Those are some of the latest SDR platforms, which can, you can actually use to build base stations. You can use to build 5G base stations, which is actually what we're going to do as soon, just a few months down the road. On the software side, there are some really interesting developments in terms of open source 5G software stack. There are two kind of, some of the early pioneers, such open air interface and SRS, and they provide, you know, open source solutions for LT and 5G. And recently there's actually another non-profit open networking foundation ONF led by well-respected networking researchers, actually Larry Peterson and Guru. They were professors before they went to start the ONF foundation. So I feel this is where we would see a lot of opportunity and excitement in the coming years and potentially even decades ahead. It has a potential to transform the paradigm on, you know, how the telecom industry and technology are going to evolve. And also who can participate, who can be the driver of those innovations. We have seen the impact of Linux on operating systems and computing, right. You know, we ask the same question. If you have the host opensource telecom solution, that's going to help, especially for what we are talking about today, like for rural broadband and how to empower kids in remote rural regions to participate in such exciting innovations. I think opensource will be a key enabler. There. Do you think creating a 5G open source software stack would be a pretty monumental task? Right? Yes, indeed. Indeed. You know, companies have hundreds or thousands of engineers developing commercial grade solutions, right? So, uh, how will this open source work? I think that's where I have a deep respect about, you know, folks for leading the ONF charge. They have actually, I think, found a good model so that, you know, traditionally, when we think about open source, we tend to think about, you know, maybe it's like one or two person spend their life days and nights and working, hacking things out. Right. And plus the open source communities. So what the ONF have been trying based, on my limited understanding so far, is that they actually find a model to have an organization. I mean, organization with very, uh, talented researchers, engineers, and they have resources to just dedicate their days and nights to the cause. So it's not like, uh, just one or two people take their like office hours working on this. It's their full-time job admission. So I think, uh, the hope is there, I think the industry is also seeing the benefit. How exactly this is gonna work out, that yet to see, but, I feel the promise is there. So. So moving on to questions related to student mentoring and teaching, my question was what is the organization of the group that handles the ARA Living Lab project? Okay. Do you have multiple teams there and each faculty has students, how do the students within each team coordinate? Yeah. Yeah. Its a good question Santosh. Yeah, indeed, you know, the effort does touch many disciplines. So we actually need students and faculty member from even within our own department, you know, from the computer engineering, but also from the electrical engineering. But we also have students and colleagues from other departments. For example, maybe just take maybe one project, right? Take the ARA project as an example. The whole team is organized into four working groups. There's the infrastructure working group, uh, led by, uh, Professor Daji and Ahmed Kamal. That's focussed on, building out this research infrastructure. And then there's the software working group led by Professor Mai and Yong Guan, thats looking at the software right behind the, you know, that's really the, the soul of the whole test bed. And then we have the research working group led by professor Kamal and Yong, that's looking at the engagement, right? Engage the broad research and education communities across the country. That's the research working group. We also have the consortium working group led by - currently in part by myself and Associate Professor, Tom Daniels, looking at how we can engage the public-private partners So overall we have these four working groups, working together with - they have their own individual missions, but we also work together to drive progress together. As far as the students are concerned, most of our students, we have to know enough about computing wireless and to some extent even control, uh, of course software to be able to work on some of projects. Yeah. But I think in general, students have been learning, uh, very well. We have been also able to engage some actually undergraduate students, even in some of the development and research work. So what are the courses that you would recommend for undergraduate and graduate students to take, to be able to be proficient in this field? Yeah. In terms of the coursework, I think for undergraduate students, I would definitely encourage you to study the CPRE 489 - Computer Networks and Data Communications. But also keep in mind, usually a course does not give you all you need. Right. So be prepared to read literature and so. You know, for students who may interested, you can go to my website. There's a link to a webpage that has information about some of the necessary training that may be needed to work on some of the cutting edge wireless research. Well, anyone who may be interested, uh, feel I'll be happy to chat. How does Iowa state compare with other US institutions in terms of research and wireless communication? You know, wireless communication itself is a broad field, right. I think, at ISU, we do have faculty members working on various areas from circuits to communications theory, to communication systems. I think we have, you know, a good coverage in general. Also with this ARA project, that also help us to hopefully serve a leader in rural broadband research. I think that's one mission we can take on, you know, hopefully contribute to the wireless research field. But pretty much, every university does have likely a wireless program. But I think one hope we have is to help build ARA Living Lab, so it can be a tool for the broader research community internally we also of course wanna think about what are the unique contributions we can make to the field and how can we organize as a team and how we can leverage error to that end. So do you have any final word of advice for our students who are interested in wireless communication? Yeah, so I think, you know, this is a field of over a hundred years age, but in the meantime it's also very young. Yeah. So overall I think, there's actually a lot, a lot of opportunities in the wireless communication field, especially with some of the mega trends now, such as softwarization of telecom where you see the convergence of wireless and computing. Also with the emergence of cyber physical systems, you see the convergence of wireless, computing and control and so on. So I think there are actually many interesting problems to be solved, and it's an interesting field to be explored. So you will not be bored if you choose wireless as your field. And also at ISU, we are here to help. You know, we love to hear your thoughts on how we can best, help you to succeed. That's all the questions I had for today. Thank you so much for our discussions. I think we learned a lot about wireless communications. Thank. You. Thank you. So for helping me, thank you.