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Analog Angle Blog

Are Millimeter Waves the Key to Easy Internet Access?

You may be familiar with Aereo, Inc., a now-defunct start-up that brought streaming TV to individuals via a “farm” of per-user micro-antennas and the Internet. Their scheme was both simple and complicated, and had modest commercial success (it was really hard to assess) but they were put out of business by a 2015 Supreme Court decision that their concept constituted copyright infringement and appropriation of content owned by others.

The founder and force behind Aereo, Chet Kanojia, is certainly full of ideas and energy. His latest startup, called Starry, plans to bring low-cost Internet access and simplified set-up and installation to RF those who are underserved or perhaps feel they are paying too much. The basis of the idea is to use millimeter-wave frequencies between local microcell nodes and the individual users.

There would be no need for any sort of wiring or having a cable installer visit: you (or the building owner) would just buy/lease the user-side Starry Beam box (Figure 1 ) with its integral phased-array antenna, and use it in conjunction with the Starry Point Wi-Fi router (Figure 2 ); on power up, the system would take care of everything needed for configuration and setup—at least that’s the proposition, see here. Starry Beam radios will sit on top of buildings to capture the incoming signals and transmit them to the Starry Point.

Figure 1

Figure 2

The building's Starry Beam (Figure 1) and user's Starry Point (Figure 2) work in a tight pairing to bring mm-wave based Internet to individual users at low cost and with simple setup - at least in theory.

The building's Starry Beam (Figure 1) and user's Starry Point (Figure 2) work in a tight pairing to bring mm-wave based Internet to individual users at low cost and with simple setup – at least in theory.

The term “mm waves” encompasses a broad range of lightly used wireless spectrum, generally considered to range from 30 GHz to 300 GHz, located between microwaves (1 GHz to 30 GHz) and infrared (IR) waves, with wavelength λ in the 1-mm to 10-mm range, see here. Using mm waves is also a technical challenge, especially as you go up in frequency. In principle, there is a lot of available bandwidth – a good thing – but also a world of very tricky RF design, costly components, and unforgiving and often temperamental designs where even a shift in ambient temperature of even a few degrees can spur instabilities and erratic performance due to drifts.

The other problems are that while mm waves have wide bandwidth potential, they also have two other well-known characteristics which can be virtues or vices depending on the application. First, they are effective for unobstructed line-of-sight links, but suffer high attenuation from unavoidable obstacles such as trees, water vapor and rain, leaves, birds, insect swarms, walls, and similar. The Starry proposal therefore will need many base stations (or equivalent) on their build-out infrastructure, which means time, money, local approvals, and more. They also plan to use some sort of dynamic directional control of the beam via phased-array design, to get the best path available at any given instant.

Second, mm waves are subject to the laws of physics, of course, and the well-known free-space path-loss equation, with loss L (in dB) = 92.4 + 20log(f) + 20log(R) where R is the line-of-sight distance between transmit and receive points (in kilometers), and f is the frequency (in gigahertz). So there’s considerable loss between transmitter and receiver, with no way around that loss.

I’m interested in this type of product because and mass-market use of mm waves, such as the 77/79 GHz used for automotive radar, brings lots of new ICs (silicon and other), experience, expertise, vendor support, tools, and more. The mm zone has been, to a large extent, untapped territory where only a few brave (or perhaps foolish, crazy, emboldened, or desperate) engineers hang out, and mass-market commercial devices are fairly rare (mil/aero applicaoit0nd are another story, of course).

I contacted Starry with three basic questions that engineers would want t known more about:

  • what specific part of the wide mm-wave spectrum did they plan on using? (One other story I saw reported it was between 37 GHz and 39 GHz, but that is not confirmed, nor is the speculation of 1 Gbps service.)
  • what is the maximum transmitting power they are planning to use?
  • what are the spectrum-use regulatory issues they face?

The answers I got were simple: “those are great questions, we can’t say right now, check with us later.” (There are, however, some technical details in the launch press release here.)

I wish the folks at Starry good luck; I think their intentions are good, the plans are ambitious, and the obstacles are many and deep. It will be interesting to find out more about their technical specifics, their implementation, and their success (or not). I’ll be trying to follow their progress and find out more; any advances they achieve may have benefits for other related and unrelated applications.

What are your views on the viability of mass-market, low-cost, mm-wave links for widespread Internet access as Starry plans, or other applications?

Related

Surprise: Aereo’s Biggest Woe May Be Power, Not Legal

Whatever Became of RFID?

My Antenna Dilemma: Preamp or Passive?

6 comments on “Are Millimeter Waves the Key to Easy Internet Access?

  1. David Ashton
    February 24, 2016

    I used to do Sat TV installs.  At one install, the user had moved into a place with a good dish but no LNB.  They'd installed the LNB themselves, facing the sky, not the dish…..  So let's say I'm a litle dubious that users can install their own phased array antennas and get them pointing right.  I guess they could get round that by having installers available for a fee, waived if signal is not available.  Also have an RSSI indicator on the antenna.  But really, if you're going to offer a 1G internet service, I reckon users would front up for the cost of a professional installation.  Otherwise a great idea, but they could shoot themselves in the foot the way they are doing it.

  2. jimfordbroadcom
    March 28, 2016

    Good point, David.  I'd had issues with rain fade on my satellite TV receivers some years ago and had a tech come out.  His solution?  Float the ground pin on all receiver boxes in the house, something that even a techie like me would have not thought of for a very long time.  That was in the standard definition days, and I noticed on the high def boxes that replaced the SD boxes, there are only 2-prong power cables.

    The point is that there may be gotchas like this with Starry's or anyone else's equipment.  There's no substitute for the experience of somebody who installs these boxes day in and day out.

  3. jimfordbroadcom
    March 28, 2016

    That's pretty funny about the LNB or LNBF (including the feedhorn) facing the wrong way!  (Forgot to include this LOL in my previous reply)

  4. David_Ashton_EC
    March 28, 2016

    @Jim… ” There's no substitute for the experience of somebody who installs these boxes day in and day out.”

    Starrys may rapidly come unstuck if they don't have techs available for this from day one….

     

    Re LNBF…I'd forgotten about the F….I came in in the KU band days when feedhorns were not really separateable form the LNB…but I did come across a couple of C band LNBFs that were like that.  

    I did take a dud LNBF apart once….didn't fix it, but great little bits of technology.

  5. jimfordbroadcom
    March 28, 2016

    Yeah, I have a Ku band LNBF in my garage lab.  Removed it from a satellite dish that somebody in the neighborhood put out in the trash.  A couple of bolts were loose on that dish, and I suspect that was why they threw it out.  I kept the LNBF, to be fiddled with some day…

  6. uberestimate
    May 20, 2016

    Very goo sum up .

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