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  5. Episode 5: Getting Creative About How to Get the Message Through

Getting Creative About How to Get the Message Through

Technologically Speaking. The Official S&T Podcast

Host Dee Saini chats with Office of Science and Engineering program manager Sridhar Kowdley about testing technology in the New Mexico desert at JamX 2022, a field exercise where S&T evaluated tactics and technologies that help responders better deal with electronic jamming. Listen in as Sridhar discusses what jamming is and gives a rare inside look into the JamX exercise—including what it’s like to conduct an exercise amidst desert wildlife. This very special episode features clips from the field test as the action was unfolding and an interesting exchange on government acronyms and actress/science inventor Hedy Lamarr.

Run time: 26:13
Release Date: August 17, 2022

Show Notes

Guest: Sridhar Kowdley, Program Manager, Office of Science and Engineering

Host: Deepak Saini, Media Strategist

[00:00:00] Deepak: Hi, I'm Deepak Saini. You can call me Dee, and I work for the Department of Homeland Security, Science and Technology Directorate, or S & T as we call it. Join me and meet the science and technology experts on the front lines, keeping America safe. This is Technologically Speaking. Welcome to this special edition of Technologically Speaking. I'm one of your hosts, Deepak or Dee Saini. Now, today, we're talking with Sridhar Kowdley, a program manager in the Science and Technology Directorate’s Office of Science and Engineering. We're talking about electronic jamming and related implications for emergency response.

[00:00:39] Back in April, we joined Sridhar at JAMX 22. We were at a New Mexico field exercise where we evaluated tactics and technologies to help responders better identify, locate, and mitigate the impact of jamming. Now, throughout this episode, we'll play clips from the field as the action was unfolding, as well as my debrief with Sridhar after he returned home from the event. Welcome Sridhar.

[00:01:06] Sridhar: Glad to be here.

[00:01:07] Deepak: In the moment we spoke with you back in April, about what electronic jamming means. I'd like to start off by playing back some of what you had to say.

[00:01:15] Sridhar: Jamming is, actually it's basically interference. Think of it this way. RF signals are out there, and they make your cell phone work, they make your Wi-Fi. Imagine, if you will, you're in a room and people are conversing in different languages. And if you put too many people in the room, it becomes so loud that you can't communicate anymore. It's essentially the same in terms of, radio frequencies that are going over the air that make your television work all the way to your cellular phones, and you want to get that signal out and jamming raises the noise so much that you can't hear. If you're jamming or interfering with any type of communications that is wireless, the call can't get through. So, whether it's a 911 call, or a police officer that, that needs some information or is requiring help. That sort of information is essential for public safety and the public at large.

[00:02:13] Deepak: That's really interesting. I can't imagine needing to call 911 and not being able to get through. Can you walk me through like some of the biggest challenges related to jamming, especially when it comes to emergencies?

[00:02:26] Sridhar: Sure. I'm sure you've encountered the possibility of sometimes, and this happens naturally, you know, you have solar flares and sometimes, when there are high solar flares, I know that people have trouble with their cell phones. They have trouble with, tried to use their wireless devices. You have the challenge of, sometimes you see in your cell phone, I'm getting all the bars, but I can't communicate.

[00:02:50] Deepak: All the time.

[00:02:51] Sridhar: You see that all the time. So, so the idea is, sometimes you get the fast busy that implies, you know, the networks are at capacity, and you don't have added capacity to support your call. But at the same time, you do end up in an environment where you could see a lot of bars that implies that your signal is very strong. And if you can't communicate, that means one of two things. One is that there might be interference in the area or somehow your phone isn't able to reconnect with the actual tower. So, you have to kind of look at both sides of the coin with regard to that.

[00:03:26] Deepak: I just find it really interesting because I don't think the everyday person really ever thinks about counter jamming at the highest level in terms of like the work, that you're heavily involved in. So, I think this is really educational.

[00:03:39] Sridhar: I think you have a very good point, but again, don't think of counter jamming don't think of jamming. Imagine the perfect storm, right? You have Mother’s Day where everybody's on their phone. You don't have capacity, you don't have communications. So, what do you do? What does a first responder do if they're relying on traditional cell phones? You know, they would go out and grab their radios that they use at the police and EMS use and say, I'm going to use my radio. Again, you have to think about if the call must go through, you have redundant paths, you have alternatives, you have other ways of addressing the problem. And so, it's just a question of, are you trained in those methodologies? So, for example, I'll give you an example, right? We weren't just looking at jamming a specific communication link. We were really thinking about how do we make communications more resilient? So, if something doesn't work, you switch to another mode.

[00:04:35] Sridhar: If you, if that mode doesn't work, you switch systems. If that system doesn't work, then you figure out an alternative way to do your job. So that's in a sense what we were trying to do at JAMX, is do the training and working with our partners at DHS CISA, we were actually developing some training programs to develop something called PACE plan, for example, which is primary, alternative, contingency, emergency. You know, it's not just about knocking the signal off, it's getting creative about how to get the message through and actually do your job efficiently and safely.

[00:05:11] Deepak: Oh, that’s interesting.

[00:05:12] Sridhar: Yeah.

[00:05:13] Deepak: Can you tell me how the JAMX 22 exercise came to be and how it relates to the previous 2016 and 2017 exercises as well?

[00:05:21] Sridhar: Well, prior to 2016, I think DHS had looked at the impact of interference on GPS systems for position and navigation. And I think that test was done in 2012, but we'd never looked at, we'd never looked at physically communication systems. Position navigation timing is sort of, relying on GPS or other signals. So, what we decided to do is, um, sort of say, well, is this a problem? And then start started looking and doing a little bit of research and we found out that it could be a problem, again. And with the reliance of, first responders, as well as those who are on DHS missions, the importance of actually getting the message through requires that we're able to have some sort of reliability and high availability systems.

[00:06:10] Sridhar: So, we were thinking, why not conduct an experiment to see, how does signal interference impact public safety networks? So, in 2016, we invited a bunch of public safety practitioners, we brought them out to White Sands Missile Range. And we picked that location because again, it allowed us to create interfering sources. And sort of see what the impact is on communication systems. And so, we found some interesting results. There was a little bit of an impact, depending on how, the interfering sources were used and operated. So, we said, oh, you know, there is something to be looked at. And then in 2017, we said, Hey, what can we do about it? So, we had another event at Idaho National Labs. And again, we invited first responders, state, federal, local folks to come out and we sort of assessed, can we implement techniques and technologies to assess and evaluate, if we could solve this problem or make sure that communication networks are more resilient.

[00:07:12] Sridhar: And again, we need to think about it in a more top-down view. The loss of communications could be attributed to not just jamming, but it could be a flood, a hurricane that would maybe drops a tower. There could be a bunch of issues that cause loss of communications. So the idea is, to come across, and implement certain techniques and technologies as well as plan for these outages and operate through. I mean, that's the critical aspect of what we wanted to look at and, this year's jamming event. So again, it was a more comprehensive look at what happens when networks become unreliable. How do I get the message through how do I continue to operate and do my mission?

[00:07:56] Deepak: Walk me through a little bit about the location. So White Sands Missile Range, smack middle in the New Mexico desert. What about this location spoke to you?

[00:08:10] Sridhar: The reason we pick White Sands is because, if we are targeting networks and doing a threat-based vulnerability analysis, it's better to do it where you're not going to physically impact, day to day lives of anyone. And you are doing it in a very controlled manner, which is why we picked White Sands.

[00:08:29] Deepak: For the folks listening, I'd like to play another clip from April when you were actually in the desert describing the environment and what we were doing out there. Again, it was in the middle of the night, and S&T and its local, state and federal partners were running through response exercises.

[00:08:41] Sridhar: White Sands has always been wonderful and also a challenge in that we're operating at night in the middle of nowhere. There's no lights. So, we have to essentially provide everything ourselves and everyone has to be self-sufficient from water to power and lights at these locations. The other challenging aspect of it is on the range, are a number of animals, including the oryx, which is a, a huge, animal that was brought over from Africa. And so, they roam freely across a range. And so that has created a number of challenges for us in order to make sure that our, users and folks at the event, not only come here safely, but can leave safely at the end of the day. So, the night is complicating things because we have very little light to operate.

[00:09:33] Sridhar: We do it at night to make sure that we don't interfere with any businesses or people using wireless devices. We also have a wide range of temperatures. We have a 30 to 40 degree drops across the environment. So, it's definitely challenging. And seems like most of the folks, especially the responders seem to always rise to the challenge to do that. We want to operate in a place and jam or interfere with technologies and wireless devices in a way that it doesn't impact ongoing public safety communications, and users and the public. So, we picked locations that are number one, allowed by the federal government to operate jammers and number two, do it in a function and our location where we can do it safely without causing harm.

[00:10:24] Deepak: Walk me through a little bit of the camaraderie there. It seems like everyone was there very passionately, to fulfill their own roles and to really learn from one another and to work together.

[00:10:35] Sridhar: Sure. There were a ton of organizations. We've had folks from Harris county, for example. Not only were they so instrumental in helping us with defining, defining the approaches and some techniques that they came up with, but, the camaraderie that they have to offer and support the activities, was significant. We had the FCC out there, they're part of the enforcement bureau that actually goes out and hunts for jammers based on complaints. And they were out there and they were working with responders and teaching them what they've learned and sort of help their colleagues and their brothers in arms, so to speak, was really pretty impressive. I mean, a lot of the evaluators, a lot of the trainers were public safety users themselves. So, it's sort of, almost train the trainer type situation where, folks that have come to previous events actually learned, and they were actually able to contribute to the learnings of new folks. The evaluators, the trainers, obviously I've seen it before. So, part of it is really that sort of camaraderie in terms of helping somebody else out with lessons learned.

[00:11:44] Deepak: Now let's jump back to our April conversation. We're gonna listen to what you had to say about the exercise itself. Not only who you were there with, but specifically what everyone was actually doing.

[00:11:47] Sridhar: At this particular JAMX event, we have about 220 people total. There are, mixed between public safety practitioners from across the country. I believe we have about 20 or 30, public safety agencies who are represented, including federal, state, local, from the public safety side. We also have a number of vendors, and users from, from federal agencies, such as Department of Drug Enforcement. Uh, we also have folks from DEA, FCC as well as NTIA. But, on the industry side, we have a number of industries who provide, technical capabilities, such as the DevOp, either communication products or infrastructure, as well as spectrum analyzers and other tools and technologies that is used by industry for scanning the spectrum.

[00:12:45] Sridhar: JAMX 2022 covers approximately five days. Three of those days are pretty much dedicated for public safety and operators. And then the other two days, the primary technology that we will be looking at is project resilience, which is focused on industry participation and working with the industry at large. The technologies that we are actually looking at fall into three main categories, one is actual communication networks, which is the critical, the infrastructure. For example, we have DOD providing 4G and 5G services because at White Sands, there is hardly any cellular service. So, for users to experience, jamming or interference, we wanted to create those wireless bubbles, coverage bubbles. We also have, folks providing, land mobile radio coverages that we are going to be interfering with. The second category tends to be, people developing spectrum analyzers and tools that allow you to scan the spectrum. The third category is we have companies that are providing capabilities to either jam or provide countermeasures. So, the countermeasures could be anything from smart antenna systems to the ability to, process signals in a different way that you can sort of work through the jamming.

[00:14:05] Sridhar: With this particular event, we want to understand, how vulnerable 4G, 5G systems are. We also want to understand, what can we do to operate through interference conditions? Thirdly, we want to figure out how do we plan for communication outages? We always talk about, Hey, we're going to lose communications because of jamming. Well, that's not entirely true. We could lose part of the network as a disaster for you, whether it's manmade or natural. And we want to be able to recover from that quickly and operate through.

[00:14:39] Deepak: Were there any nice nuggets of surprises or anything you didn't expect that came out of JAMX 22?

[00:14:46] Sridhar: I'm not sure there were any surprises. But like I said, I'm always humbled by the responders and the amount of dedication that they provide to support us and support themselves in sort of contributing to the whole. Part of the concept that we were looking at is whatever we learn from here is going to be sort of rolled out nationwide. So, all responders can benefit from the event. Whether it's training, whether it's fine tuning our procedures, whether it's, actually making sure that communications are resilient by following the tips and tricks. So, I'm always surprised by the length at which the responders go to, to kind of contribute to the overall project. And then the second thing is that, we did learn that, technology could be a solution. We found we, at DHS has developed some technologies to provide responders with some tools and techniques to allow them to identify and locate jammers or signal interfering sources.

[00:15:48] Sridhar: And so, we found that, and industry was a great partner as well. We had a bunch of folks come out, that actually provided a spectrum, scanning technologies, spectrum analyzers and other tools that someone could use to actually identify and locate interfering sources and essentially take them out of commission. At the base level, responders ought to be able to take the lessons learned in terms of, Well, how do I operate my radio? How do I operate it in a manner that is, gives me the best performance in the field? How do I know that I've been jammed? If I detect that I've been jammed, who, should I report it to, what data do I need? It sort of starts from, the identify, identify that something's happened to my communications system. The other is, locate, can I locate what the source of the interference is? Can I locate what the problem is? And the third is operate through, right, or mitigate. How do I work around the conditions that I was subjected to? So, I would kind of break it up and, I think that's the progression that we want to get to, the mindset, to kind of detect, identify, locate, and mitigate.

[00:16:32] Deepak: Before I pivot into some more general questions. I wanna leave listeners with one last clip from our last conversation about warning signs of jamming for responders and the public.

[00:17:08] Sridhar: There are some warning signs DHS has put out some infographics. For example, you may see a lot of bars. You may see full bars on your phone, but you can't make a call. That's sort of an indication of potential interference. There are other indications of, of, interference signal and interference or jamming. But that's a key one. That's a very simple one to look at. If you have multiple devices that, you know work generally well, but all of a sudden they don't work in the same location. There might be something going on that you may want to be concerned about. I think, with regard to responders using wireless devices, very simple. If a police officer wants to call an ambulance and he's using his cell phone to do that, obviously he can't, or if he's using his radio and the signal is not going through, he's not going to be able to do his essential mission or function. If he needs to coordinate with other first responders and sort of have an efficient response, he's not going to be able to do that.

[00:18:09] Sridhar: Other folks, for example, in a firearm incident command, where they're tracking people, in terms of where the firefighters are for their safety and being able to direct them or give them directions or instructions. They're not going to be able to do that. So, from a public safety standpoint, communications is vital and essential, and that those are the functions that are driving us to kind of look for ways of improving communications resiliency. So, this particular event is not just about jamming, but it's sort of understanding how do I improve my communications, make sure that it's available all the time.

[00:18:45] Deepak: It's been great talking about the JAMX 22 exercise. You know, everything that we do kind of falls under the science umbrella. Sridhar, when it comes to the word science. What does that word evoke for you? 

[00:18:58] Sridhar: Yeah, it's sort of the basis for everything that we do and how we live.

[00:19:03] Deepak: Isn't that the truth though?

[00:19:05] Sridhar: It's how we, get up and make a cup of coffee. That's science related to the coffee, right.

[00:19:11] Deepak: So why are stories about science and technology so important?

[00:19:15] Sridhar: What we use science and technology for is to make us safer ensure that we can live happier, healthier lives. I think that the contributions that we are looking at making at least, whether it's the first responder community or the public. Our goal is to actually work towards that. So, I think, part of why we live. As long as we do is because of science.

[00:19:40] Deepak: Exactly. What is your first love of science memory? Do you have a certain thing that was an aha moment for you when you were really young, that just kind of made you realize this is it? Science is for me.

[00:19:53] Sridhar: I think it was, I think it was the work that NASA was doing. I do remember having all of the shuttle specs and I even had a cutaway of the NASA space shuttle on my wall as I, when I was growing up. And to me, that was the cool stuff.

[00:20:15] Deepak: That's so neat. I could picture, little Sridhar sitting on his bed,

[00:20:19] Sridhar: Well, it's.

[00:20:20] Deepak: out his window, dreaming about NASA.

[00:20:22] Sridhar: Well, I will tell you that that's a double-edged sword. One of the worst days in terms of interviewing happened to me because of the shuttle. My first job, I had three interviews with three different companies who all lost the shuttle on the day of the interview.

[00:20:40] Deepak: Was that the Challenger disaster?

[00:20:42] Sridhar: That was, exactly right. And I went I had three interviews that day and they were all, each of the companies had lost equipment on the shuttle that day, and everybody was a basket case.

[00:20:56] Deepak: Oh, I bet.

[00:20:57] Sridhar: So, it's a double-edged sword.

[00:21:00] Deepak: Yeah. Some, what's interesting though as awful as that was, sometimes the most learning or lessons or tools, or just things that help us progress and move forward kind of comes out of those situations. So they don't happen again. Hopefully.

[00:21:18] Sridhar: That's true. That's true.

[00:21:19] Deepak: How young were you when you realized like this is the field that I'm kind of falling into, were you more excited in some sort of your like math and science sort of classes versus maybe some of the creative arts ones?

[00:21:32] Sridhar: Well, actually, it's always been STEM for me. The track that I took as I went to engineering school at the university and all of the colleges I applied to were primarily engineering schools, but, I got into Columbia University and probably in my sophomore year, I took a course on information theory. And, one of my favorite professors and he really flipped the switch in terms of something that I gravitated towards and I really enjoyed it. It was basically a communication theory, uh, everything from, how do you design filters to, how do you recreate communication system? You know, you sort of sample technologies, how does a cell phone work?

[00:22:12] Sridhar: You basically have to create the digital to analog or rather the analog to digital, and you have to follow the signal processing chain. And that's sort of the switch that got flipped for me. That's when I started getting into communication networks and engineering related to those, type of, topic areas.

[00:22:32] Deepak: That's really interesting to hear sometimes what makes your brain tick, or just even the teachers that influence us to make the decisions we do in our career. What led you to starting at the Science and Technology Directorate?

[00:22:46] Sridhar: I had been doing communication networks for a long time, specifically, about 10 years or so of my life, I did mostly satellite communications, primarily in the defense area. So, we were conducting testing and design and test and evaluation of satellite payloads. Subsequent to that, I spent a bunch of time doing design of wireless networks, commercial wireless systems, including CDMA, GSM. And then I started looking into the civilian world and I started doing a lot of work with DHS. What really introduced me to S&T is when I was at CBP as a contractor, we engaged S&T to conduct some research to solve the next generation wireless system technology gap that we wanted to be solved. And that was my first introduction to S&T. I really enjoyed the work that we did together with CBP and sort of built that relationship forward.  That interest, or rather the, the engagement sort of gave me visibility into what S&T does, and then drove me to join S&T.

[00:23:55] Deepak: Now that you've been here for a while. You know Sridhar, there's so many acronyms across DHS in general? Do you have any favorites?

[00:24:05] Sridhar: Favorite acronyms?

[00:24:06] Deepak: Yeah.

[00:24:07] Sridhar: Boy, I'm not a huge fan of the acronym.

[00:24:10] Deepak: I'm not either. There’s too many.

[00:24:11] Sridhar: There's too many of them. Yes. I think one of my favorite was, spread spectrum over, uh, spread spectrum dynamic access, spread spectrum mobile radio. So, CDMA is another favorite one that I, got used to when I started doing my master's thesis, which stands for code division multiple access. And actually there's a great story behind it. Hedy Lamar was a famous actress and, she actually is credited with identifying the ability to, to create something called spread spectrum. And what that means is that if I stay on a specific frequency, right, the enemy can find me. So for example, in World War II, they were talking about radio-controlled torpedoes that were actually aimed at the allies ship. Or rather the allies were using radio-controlled. And if you jammed that signal, guess what would happen is that, that torpedo would be ineffective. And so, she sort of said, well, what happens if I jumped frequencies? Right. And I jumped the frequencies in a predictable manner so that they don't know where I am or they can't keep up with me, then I can continue to control the torpedo. And so, so she's kind of credited with spread spectrum technologies and there's two varieties. One is frequency hopping, as I mentioned, and the other is called code division multiple access. And that's where it came from.

[00:25:34] Deepak: It's been great speaking to you and thanks for joining me for today's episode of Technologically Speaking. I enjoyed learning about counter jamming and hearing about the exercise.

[00:25:44] Sridhar: Thank you, guys.

Deepak: This has been Technologically Speaking, the official podcast of the DHS Science and Technology Directorate. To learn more about S&T and find additional information about what you heard in this episode, visit us online at scitech.dhs.gov and follow us on social media at DHS Scitech. Thanks for listening.


Last Updated: 04/19/2024
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