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The Drone Dilemma, Part 1: The Lack of Bandwidth and Signal Strength

I have been holding off on writing about drones yet I now believe that it is time to touch on this subject. Drone aircraft is so interesting to me that I became a Technical Editor for a website on drones. My interest in drones parallels the advancement of technology that many Planet Analog audience members contribute to. This blog in particular is focused on two of the main limitations that drones face: available bandwidth and signal strength.

Drone navigation relies on the availability of bandwidth simply because these devices are controlled by wireless signals. Therefore, they rely on remote guidance that is transmitted via the regulated frequency spectrum. This guidance comes in many forms including: GPS, interaction such as Wi-Fi/cellular/dedicated airwaves, and sensor interaction. This is all great except for one thing, there is limited bandwidth available already. So where are we going to put these many, many additional signals? Drones do have a place on the spectrum. Some bandwidth from an unused frequency for weather data transmission was allocated for use. I fear that it will be gobbled up faster than SMBus was.

If you look at the frequency spectrum allocations of the United States [1] alone, I’d suggest that you have an incredible zoom capability on your computer or a very strong magnifying glass. You’re going to need it because the spectrum is very crowded. It is getting more and more crowded everyday as we keep adding wireless devices as well as increasing the number of bits that each one transmits.

In July of 2015 there was a Planet Analog webcast on drones. I spent most of my time making the other attendees aware of this issue of limited bandwidth. Whereas many people are concerned with flight paths, privacy, and regulation; few touched on this subject of wireless control.

In order to understand the drone bandwidth dilemma, search #drones on Twitter. I recently did this and found some interesting articles. They all point to creating more traffic on the already overloaded air waves. Included in these articles is a reference to the Amazon patent [3]. A quick glance at it shows that Amazon must deploy communications points around the area of delivery. All I can say about that is you will see the same old, same old dispersion maps that followed the cell phone generations of 2G, 3G, 4G, spare me. In other words, mountain dwellers like me will not be in an area that is densely populated enough to deliver a package to.

There will be no ROI for communications points the same way there isn’t enough demand to justify a cell tower. I’ll have to go into town to get my package just like when I want to make a phone call. I don’t see packages coming through the other wired or optical interfaces such as land lines and cable. Physically that’s impossible. Although the proposed drone navigation techniques of the Amazon patent are possible, they certainly face the limitations that I have outlined.

Spectrum isn’t the only limitation that drones face. Signal strength is the other issue. I spent three weeks analyzing a recent version of the 802.11 Wi-Fi specification. My original notes contained 100 PowerPoint slides illustrating why this document is an attempt to make up for the inadequacies of QAM signal transmission technology.

In the end, I whittled it down to ten slides that described the dilemma. Although the Wi-Fi specification was created by some very intelligent contributors from the world’s foremost communications companies, it really was a band aid fix for poor signal strength. Why else would you need three transmit sources to reach maximum data transmission capacity? The sources and receivers also must be placed in a manner that aligns the signals through beam forming. Some of you may remember a cell phone commercial that applies here.

“Can you hear me now?”

“Can you hear me now?”

“Can you hear me now? What? You can’t? I must be standing in the wrong place.”

Getting maximum data will revert to the old days of having to get up and adjust the antenna on the TV. To me, that’s not progress.

In addition to having to steer signals, the source and the receiver have to identify each other as “capable” of the latest Wi-Fi specification. Is it me or did we just waste a bunch of time identifying each other that could have been used to transmit data? I hope you see my point here. We are resorting to methods of communication that would be unnecessary if there was a stronger, faster signaling solution.

As a final thought on signal strength, the local news just indicated that Christmas lights might be interfering with your Wi-Fi. Really? Anyone out there needing a crashed drone on their lawn next to Santa?

Like anything, the control signaling that drones require will be resolved with new technology. However, the majority of new technology that investors are backing is software. Any software company that mentions the word “platform” gets funded even if they are making incremental changes that everyone else is already doing. It’s almost a parallel to having the word “swamp” in the title of your reality show. Those words seem to generate interest no matter how impactful the product they represent is.

“Choot him! Choot him!”

Sorry, had to get that gator. Where were we? Oh yeah, the limitations that software has in wireless transmission.

Software compression has also made its way into the new Mike Judge show, “Silicon Valley” where a startup war is created when a compression algorithm invokes a disruptive change that is the next big thing. Just remember one thing investors, you can generate all the software in the world and compress it down as much as you want. However, without a means to transport it by, there will always be a data sphincter that limits communication. The secret to freeing up the spectrum is to generate new hardware techniques that enable more digits to flow. This provides an express highway for all of the little software ones and zeros that run along it. When you invest in software, you are funding a bunch of additional Walmart shoppers while not adding anymore checkout stands. This is ludicrous.

Freeing up the spectrum is akin to creating more lanes on the freeway. Stronger, faster signals are similar to increasing the speed limit. Solutions to both the transmit speed and bandwidth are available right now. Getting them funded is another story. Unlike software, hardware for some reason scares investors. Perhaps they believe everything that can be invented already has been patented. Maybe that’s why Amazon’s patent focuses more on loading the system down than speeding it up. Maybe the technology patent of which I speak should be changed to “swamp platform for expanding the bandwidth”. It has all of the right buzz words.

“It’s Mike from the mail room, he DJs on weekends.”

I apologize to the engineers that are still reading this. I had to throw a carrot to the board members that haven’t left in disgust by having to face reality that software isn’t the only answer.

“Cell phones will never leave analog for digital,”…..said Motorola somewhere in the 90’s.

Ayup, and software is the only answer. By the way, did you happen to notice the headsets that football coaches wear once had a Motorola logo on them and now have a Bose logo on them?

In addition to my own views of this situation for controlling drones, there is data available to back up the claims that I make in this blog. I will borrow a line from reference [4]: “As early as 2005, a study of UAV crashes suggested that improved interfaces may reduce the number of accidents.” Maybe hardware is a viable investment after all. But then again you might have to just settle for Mike from the mail room while competitors eat your lunch. Gotta go, the Amazon drone just delivered my razor from Dollar Shave Club. (In addition to technology investments, I was known to disrupt the classroom as well). No gators were harmed during the writing of this blog.

References

  1. United States Frequency Allocations, Radio Spectrum
  2. “When Drones Crash: The Looming Tech Threat That May Cause Countless Drone Deaths” Scott DeutyJun 11, 2015
  3. “Amazon Patent Reveals How Delivery Drones Could Avoid Crashing Into Your Home” Ryan Mac, Staff writer covering technology and e-commerce, December 3, 2015, Forbes website
  4. “WHAT CAUSES SO MANY DRONE CRASHES? THE ANSWER IS A LOT SIMPLER THAN YOU’D THINK.”By Kelsey D.

1 comment on “The Drone Dilemma, Part 1: The Lack of Bandwidth and Signal Strength

  1. nathandavidson
    July 24, 2018

    From a layman's perspective, i.e. mine – I really never knew that our networks could be that crowded! Everybody just assumes that all these data packets flying around in the air are free to go wherever they like but never quite understand what causes downtime and congestion on the access that we get. Now I know. That is the most colourful layered cake I have ever seen, if I do say so myself!

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