The Feds as CheerleadersTuesday, May 06, 2008
What do the National Telecommunications and Information Administration (NTIA), the Federal Communications Commission (FCC) and the Federal Energy Regulatory Commission (FERC) all have in common? The answer is that for the last three or more years, these agencies have been actively promoting (cheerleading) the use of Broadband over Power Lines or BPL as the "third wire" to take broadband to many places in the United States where it is not available today.
The basic idea is to put a broadband radio frequency signal on our power lines, including high-tension lines, and transport the signal over the power lines to homes along the route. After all, most of America's homes do have electricity and this would be a great way to get broadband to all of them. This sounds great to those who do not understand much about radio frequencies. The fact is that wires are great antennas, so not only do they carry RF, they send it out into the air along the entire route of the power cables. A number of other issues with using BPL for broadband distribution include getting around the transformers that step down the power from a very high 660 volts and higher to standard household 220, which is split in the house to provide two legs of 120 VAC. The number of transformers that have to be bypassed is dependent on the route that is used for BPL transmissions, but it could range from one to four or more.
Over the past few years, various schemes have been used to get around the transformers, including one that uses Wi-Fi at each transformer. Motorola used to have a product to distribute broadband via a Canopy network (wireless point to multi-point) and then used AC power lines from the pole into the house. This product is no longer available since it did not meet Motorola's expectations for a volume product.
The most significant issue is that when you put RF on a wire-or a pair of wires, especially those that have no insulation or shielding-the RF not only flows down the wire, it also radiates into the air. Wires have been used as antennas for a very long time and perhaps you have had an experience where your stereo speakers had voices or sounds coming out of them from time to time that are not coming from your own audio system. This is because the wires between your amp and speakers are acting like receive antennas and, depending on their length and the source of the interference, they can generate sounds in your speakers. In this case, the fix is easy. You simply attach a couple of capacitors between the leads at the speaker end of the wire and the problem usually goes away. However, you cannot do the same thing when the wire carrying the RF signal is radiating that signal down the entire electrical system.
BPL and the interference it causes is a problem for several reasons. First, it can interfere with two-way communications in the 30-50 MHz band, a band that is used by the California Highway Patrol and many other agencies that need to cover large areas in rough terrain. Next, it interferes with amateur radio receivers in any number of bands they are licensed to operate on. The American Radio Relay League (ARRL) has proven time and again that BPL does interfere. Perhaps the FCC, NTIA and FERC are not worried about interference to bands in which licensed amateur radio operators are operating as a hobby, but there is more to it than that. During many different types of disasters (including Katrina and the World Trade Center), ham radio operators provide communications for emergency groups who need it because their own systems are down or overcrowded. These amateur radio operators also work in conjunction with the Red Cross to provide one of the few conduits available for people who are looking for relatives and loved ones. If they cannot operate without interference, they cannot provide their services.
Let's take a look at some figures that were recently published in the ARRL monthly magazine QST. It admits that it is difficult to track numbers of BPL customers, but according FCC records, the number of subscribers is less than 5,000 nationwide. However, in a recent TIA report, it was claimed that the BPL population is more than 200,000. It seems that the TIA was using data from a research firm that lumped BPL and several other forms of broadband access into a single category and the TIA reported the total number of customers in this category without trying to come up with a more accurate number. Why is this important? BPL, like Muni-Wi-Fi, was to be the be-all, end-all for providing rural America with broadband access and through all of the hype, it has basically been a failure-but our government is still pushing it. There are some electric companies using BPL for their own internal data communications, but on the whole, BPL is one of those technologies where the problems outweigh the benefits and the cost to deliver data over power lines makes it cost prohibitive.
The solution for providing broadband to rural America is not BPL, nor is it WiMAX at 2.5 GHz, Wi-Fi, satellite or the next big thing. If we are serious about providing broadband access for rural America, we need to put together a system that is perhaps a combination of technologies on a number of segments of spectrum. I think we can use the 700-MHz D block as the prime access mode for much of rural America as part of a nationwide, coordinated plan.
The government's job is not to act as a cheerleader for a technology it thinks is "interesting" such as BPL or unlicensed white noise. Rather, it is to have its engineering staff review and test the technologies, weigh the pluses and minuses of each and then make recommendations that are followed by the Commission. Unfortunately, it appears those days are over and what we are left with is a politics and damn the consequences attitude!