Last week at the IEEE Broadcast Symposium in Alexandria, Va., a panel discussion on spectrum issues related to the FCC's National Broadband Plan highlighted a paper by Alcatel-Lucent Bell Labs scientists as well as opposition to the plan from weather-related groups worldwide. This got me thinking about the impact of the National Broadband Plan on the environment. It doesn't look good.
The IEEE panel discussion highlighted the need for more spectrum for mobile and portable devices. Rick Engelman from Sprint displayed a graph showing that much of the projected increase in demand for mobile broadband spectrum is due to increasing demand for mobile video. He pointed out that broadcasters could partner with wireless carriers to offload some of that demand using Mobile DTV.
Broadcasters can deliver the most popular content much more efficiently using less spectrum than wireless Internet connections. This is because Internet video delivery over the Internet requires a separate connection to each viewer. Broadcast video uses the same amount of spectrum to reach a million viewers as it uses to reach one viewer. Forward error correction and more robust modulation make broadcast video inefficient for reaching a small number of viewers, but I'd estimate that as the number of viewers exceeds a dozen or so broadcasting is more efficient. If the millions of people that now watch popular TV shows, sporting events and breaking news stories try to watch these broadcasts in similar quality over wireless Internet instead of over broadcast TV (cable, satellite or over-the-air), the wireless broadband carriers will need a lot more spectrum, far more than broadcasting uses now. This spectrum will have to come from other services.
Broadcasters aren't the only ones whose spectrum is being targeted for wireless broadband. In the Nexgov.com article, Bob Brewin reports that groups including the World Meteorological Organization (WMO), weather agencies in countries including Vietnam and Canada, state and local agencies, and commercial weather service providers in the U.S. oppose the National Broadband Plan's recommendation to reallocate spectrum used by weather satellites to commercial cell phone carriers. NTIA plans to give up 15 MHz of spectrum for broadband use.
Bob Brewin quotes a letter Michel Jarraud, secretary-general of WMO ,a United Nations Agency, sent to the FCC saying the NTIA plan could influence other countries to try the same thing, which "would put at risk meteorological and hydrological activities worldwide" and jeopardize a global system whose operation costs run between $2 billion and $3 billion annually. "There is no alternative to spectrum for METSAT [meteorological satellite operations], and no alternative frequency band that can provide similar reliable and available service." Brewin's article has quotes from representatives of agencies and companies depending on weather satellites and wireless monitors used to measure stream water flow that would be adversely affected by reallocation or sharing of their spectrum.
While broadcast engineers that just completed the DTV transition and who are now working to bring Mobile DTV to the public might disagree, broadcasting is not only more efficient, but much simpler, uses less resources and is more reliable during natural disasters than wireless broadband Internet for delivering video to consumers. The signal from the TV transmitter can be directly received by the consumer. While cable TV is an option, it isn't essential in most cases. Although some additional transmitters may be needed to reach distant or shadowed areas, broadcast TV is already available to the vast majority of households without the need for new cell phone towers.
Cell phone and smartphone users are becoming aware their devices have to transmit to connect to the Internet and are concerned about the impact the RF from these transmitters may have on their health. Most are not aware that power increases exponentially as you move closer to the transmitter, making that cell phone in your hand a far greater threat than that cell phone tower a few blocks away or that tall broadcast tower in the middle of a large field outside of town or on a distant mountain top. While the impact of low level RF on human health is still controversial, broadcasting and wired-broadband expose the user to far less RF energy as neither requires a transmitter in the device the consumer is using.
By now you may understand why I started seeing the National Broadband Plan's emphasis on wireless broadband at the expense of other spectrum users as a threat to the environment. First, broadcasting is far more efficient at transmitting video and audio programs to more than few people at the same time. And it's not only more efficient in spectrum use, but in power use and the amount of equipment required. In their presentation at the Frontiers in Optics 2010 annual meeting in Washington D.C., Alcatel-Lucent-Bell Labs scientists addressed the equipment issues, noting that gains in network energy efficiency are not keeping pace with traffic growth. Their solution is to move traffic to fiber optics and away from wireless networks. Dan Kilper, a member of the technical staff at Bell Labs and chair of the GreenTouch Technical Committee said, "Our findings also showed that optical transmission gear consumes more than a factor of 10 less than other network technologies such as cellular base stations and packet routers," Broadcasting and wired, not wireless, broadband is far more energy efficient.
Finally, agencies and companies that depend on spectrum the NTIA is planning to give up for wireless broadband have expressed concern that loss of this spectrum will threaten their ability to monitor the weather and stream flows.
It is clear that as the use of smartphones and other Internet connected portable devices grow, more spectrum will be needed for broadband. On the other hand, the amount of spectrum needed and the impact of the transfer of that spectrum would be reduced if broadcasting becomes part of the broadband solution. Delivering video programming and other "broadcast" content to thousands of devices at one time via broadcast, as well as via fiber optic and other wired networks in conjunction with very low power in-building transmission systems (perhaps using "white space" devices on unused TV channels) would lessen this impact if they were given a larger position in the National Broadband Plan.
