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Mobile Cell Phone Towers For Disaster Relief

Posted by timothy on from the well-seattle's-a-reception-disaster dept.

cerberus4696 writes "According to today's Denver Post, Verizon recently premiered one of its new Cells On Light Trucks (COLTs), a complete, self-contained CDMA cell that can be moved to wherever it's needed, such as the scene of a natural disaster or a large public event. Since a standard CDMA cell can only handle a theoretical maximum of 62 calls at a time (usually less in practice), the network of permanent fixtures can quickly become overloaded in high-use situations. Verizon already uses a larger version of the system known as a Cell On Wheels (or COW; gotta love these acronyms), but as it takes three trucks and the better part of a day to deploy, nimbleness of response has apparently been an issue."

8 of 210 comments (clear)

  1. wow, only 62 calls at once? by Anonymous Coward · · Score: 5, Interesting

    That seems really limited. Hell, I bet my local high school would saturate a cell every time class let out, there were always people making calls or listening to messages. I'm surprised I don't see more towers with the number of cell phones I see daily. Of course, I am from Seattle, so the lousy reception they mention applies to me :(.

    Anonymous Coward

    1. Re:wow, only 62 calls at once? by Phil+Karn · · Score: 5, Informative
      That figure is a little misleading. 61 (not 62) is the number of available traffic channels per sector and per RF channel for the original mid-1990's IS-95 CDMA standard. The number 61 comes from having 64 Walsh code channels, minus three for overhead: pilot, sync and paging.

      Sectorization refers to the practice, common with all cellular technologies, of dividing up the area around a cell site into regions, or sectors, each served by its own set of directional antennas. Three sector cells are extremely common; that's why so many towers have triangular platforms with a set of antennas on each side. There are usually three antennas on each side: one for transmit and two for receive, with the extra receive antenna providing spatial diversity.

      Most CDMA cell sites in built-up areas have three (or six) sectors, operate on more than one 1.25 MHz RF channel, and use the newer CDMA 2000 1x standard. That can easily provide a total cell capacity of considerably more than 61 calls.

      CDMA 2000 1x doubles the number of Walsh code channels (to 128) by adding a second set of traffic channels in quadrature to the original 64. Virtually all CDMA phones sold over the past few years do 1x.

      Because of CDMA's inherent robustness, the same RF channel can be reused in adjacent cells and even adjacent sectors, greatly increasing the overall capacity of the spectrum in a given area. Because no careful frequency reuse plan is required, CDMA is also very well suited to the rapid deployment of cells in "hot spots" as described in this article.

      Disclaimer: I work for Qualcomm.

  2. COWs? by daringone · · Score: 5, Funny

    If you put a cell on a COW, can you tip it?

  3. Because communication IS a good thing... by YankeeInExile · · Score: 5, Insightful
    Said the troll dripping with sarcasm:
    because we all know in the event of a majour natural disaster the first thing we all want is cell phone coverage back :-)

    Communication actually is the first service that is needed after a natural disaster. It just turns out that cellular service gives the best bang-for-buck in terms of communication capability.

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  4. Natural (or other) disaster by ffejie · · Score: 5, Insightful

    This could be an incredibly useful technology. Anyone who had someone in New York/DC during 9/11 knows how difficult it was to get a hold of anyone that day. Aside from the fact that cell towers went down with the WTCs, Verizons CO (central office) was right next to Tower 1 and 2, knocking out quite a few landlines. Switching capabilities were compromised, leaving most of us with "All circuits are busy." In the future, deploy a few dozen of these and the cell phone capacity could ramp up rather quickly in an extreme event.

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  5. Re:So... by daringone · · Score: 5, Interesting

    If you're on a network that promises "No Roaming" such as Sprint's Fair and Flexible America or Alltel's Total Freedom, it shouldn't matter what company puts up the tower... you can use it.

  6. Llamas? by op00to · · Score: 5, Funny

    Verizon has taken even more dramatic action to cope with disasters in the past. In 2000, during the Hi Meadow fire near Bailey, the company used helicopters and llamas to transport equipment to the rugged terrain, Weaver said.

    Did anyone else notice this? Llamas. And helicopters. Sounds elaborate. Makes me glad I'm not with Verizon.

  7. Re:Traffic by Crinos · · Score: 5, Funny

    Yes, and they would call them Portable Instruments to Get Service (PIGS)

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