Wednesday, February 11, 2015

The Motorola GMRS network

So this is a thing. If you use high-end walkies-talkies you are probably aware of this top-tier pricing option.Following the relative inaction of the FCCs proposed 2010 rule-making, GMRS (General Mobile Radio Service ) repeaters still require a license as previous.  I've written about walkies-talkies a twice before but this is a unique service worth discussing. It's a walkies-talkie network.

Walkies-talkies can communicate directly, one to one with no intermediary devices or services. If you've ever bought one you know that this is the cheap end of the pool. There are problems with this  typically analog service. Large buildings, hills, and sources of interference can obstruct reception. But most of the walkies-talkies in this group are basically toys.  They operate at low power, literally half a watt. In this application walkies-talkies are often referred to as HTs, for handheld transceiver. While this may work well in an open area, there will be issues indoors. There are a number of solutions to this but many of them require an FCC license. There is a great synopsis of features and spec here.

The typical solution is to increase the power, and use a GMRS repeater. This repeater's antenna can be installed at a high elevation point to mitigate areas of null reception. Some vendors insist at this point that the device is no longer a walkie-talkies but is a "commercial 2 way radio." This is marketing bunkum and should be duly ignored.  However, it's worth noting that many users avoid this scenario because that GMRS repeater requires a license. But there remains another option.

Motorola has carefully patched together what I consider to be the first walkies-talkie radio network. Using "commercial partners" i.e. their distributors, as proxies they have made significant progress building a GMRS subscription model. These resellers/network providers include:  Utah Communications, New York Communications, Triangle Communications, Comtronics, Mohre Electronics, Illinois Communications, Maine Radio, MCE Wireless, Telecom Communications,  and many others.  Instead of buying your own GMRS repeater, and having to maintain your own license you more-or-less just subscribe the theirs. Using TDMA and frequecy allocations they can cram a surprising  number of subscribers onto the same network.

Motola intends to expand the service to become a ubiquitous Nextel-like service. The twist here is that because these all-digital networks are transmitting data over two-way radio, these local monopoly networks may eventually find themselves classified as ISPs. Their own documentation notes a data rate of 9600 bps which is not much, but certainly could be all that's available in some rural areas. Old PSTN dial-up networks offered 300 bps, so it's not unthinkable that this may be inadvertently included in the new ISP-as-a-utility legal concepts.