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Broadband Over Power Line and Amateur Radio Ed Bruette, N7NVP ARRL WWA Section Manager n7nvp@arrl.org 360-698-0917. Questions of the day. Who has been promoting BPL? Is it a realistic threat to Radio?. Show Broadband over Powerline Primer video here. In the US, Regulated by FCC Part 15.
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Broadband Over Power Line and Amateur RadioEd Bruette, N7NVPARRL WWA Section Managern7nvp@arrl.org360-698-0917
Questions of the day • Who has been promoting BPL? • Is it a realistic threat to Radio?
In the US, Regulated by FCC Part 15 • BPL has been legal all along under FCC rules • On October 14, the FCC made significant changes to the rules governing BPL • Although they spun it as rules to “enable” BPL, it “enables” only in that it attempts to address interference issues • In reality, the new rules put significant new restrictions on BPL
What Was Kept? • Absolute-maximum limits defined in Part 15 • Carrier-current must meet limits for intentional emitters • Part 15 also is clear that unlicensed devices such as BPL must not cause any harmful interference and they must accept any interference caused to them • Manufacturer responsible for FCC authorization and maximum limits • Operator responsible for harmful interference • Both components to the rules are necessary for Part 15 to work
What is New? • Interference Database – Zip code and contact information • Mandate to have ability to control frequency, power level and shut off • Certification instead of Verification • List of forbidden frequencies • FCC said interference would be “very rare” but carved out 13 blocks of government spectrum that BPL couldn’t use • Operate under “transition” rules • Devil in details – will define what constitutes interference?
Intentional Emitter Radiated Emissions Limits - HF • Sec 15.209 • 1.705-30.0 MHz -- 30 V/m at 30 meters • These limits should protect users of the spectrum against interference, yes?
No! • If the absolute emissions limits were set to offer unconditional protection to all radio services, the permitted levels would be unworkably low • Amateur Radio Service, by design, uses sensitive equipment and weak signals • The “legal limit” will result in a strong signal to nearby amateur HF installations • On 3.5 MHz, a half-wave dipole placed in a 30 V/m field will receive a –86.4 dBW signal (338 V across 50 ohms) • To amateurs, this is S9+16 dB – clearly harmful interference to typical amateur communications! • Harmful interference at even greater distances than the compliance distance is likely • The absolute limits are not enough to prevent interference to nearby receivers
Harmful Interference • Defined as the repeated disruption of radio communications or any disruption of certain emergency communications services • Merely hearing a signal is NOT harmful interference • 30 V/m at 30 m works to a degree for discrete frequency signals • If from broadband device, however, will interfere with entire band(s)! • 30 V/m works to a degree for isolated point sources • If from PLC, level will occur for entire length of line in areas where access PLC is deployed!
Harmful Interference – the BPL Perspective "It is Progress Energy’s position and interpretation of the FCC's rules with regard to 'harmful interference' that any interference that may still exist is not 'harmful' as that term is defined by the FCC's rules," Len Anthony, PEC's attorney for regulatory affairs, told James Burtle, chief of the FCC's Experimental License Branch. "This level of interference does not seriously degrade ham radio operation or transmissions or cause repeated interruptions." The FCC defines as "harmful" any interference that "seriously degrades, obstructs or repeatedly interrupts a radio communication service operating in accordance with the Radio Regulations." Anthony noted that since PEC can modify its Amperion BPL system to totally eliminate interference to fixed stations, "the only impact of any kind upon ham operations is upon mobile operators." PEC concluded that since BPL interference to mobiles would by "very short lived," the company is not causing harmful interference and is in "full compliance" with FCC Part 15 rules.
BPL Misconceptions • BPL is a solution for rural America • Not cost effective • No back up power • VOIP • No 911 • Connectivity during disasters
How do I know it is BPL? • It is possible to misidentify BPL • Each BPL system has a unique sound • Some are spread spectrum – broadband noise • Some are OFDM, broadband noise or multiple carrier • Onset vs spectrum is generally over about 100 kHz • If the noise has a strong 60- or 120-Hz component, it is probably “regular” power-line noise • If heard every 10-50 kHz, as a buzz or as birdies, it is probably a computer, TV set or switch-mode power supply
Emergency management National Guard US Coast Guard U.S. Military Fire Departments Law Enforcement CAP FAA FEMA NASA Voice of America TV stations Amateur and CB radio BPL Could Interfere With:
Power Lines as Antennas • EZNEC 3.1 used to model 300 feet of simple electrical wiring (uses NEC-4, written by Lawrence Livermore National Laboratories) • ARRL’s modeling showed “gain” of –16 dBi on 3.5 MHz to +10 dBi on upper HF • This is about the gain of a mobile whip on 75 meters and a 3-element Yagi on HF
Analysis • ARRL’s filing contained an analysis of the degradation of HF Communications by Part-15-level signals • Over 70 dB increase in peak local noise – on entire length of line – in whole neighborhoods! • Overseas measured studies showed similar results to ARRL calculations
Other organizations that share ARRL’s concerns: • Federal Emergency Management Agency • National short-wave listener associations • Short-wave broadcasters • Aeronautical • NTIA has done field measurements in Potomac, MD and Emmaus, PA • They released a report on their findings
Is Amateur Radio Doomed? • No! • In a speech last year, FCC Commissioner Abernathy stated that she envisioned that most rules that were restricting BPL could be removed. • In a letter issued several months later, she clarified that protection against harmful interference was a “bedrock” position. • In October, 2004, the FCC came out with an announcement of new rules that removed NO restrictions, but proposed to add requirements that apply to no other unintentional emitter • The work being done by amateur radio IS having an effect, and we can continue to drive home the point to the FCC and to electric utilities that power lines are not the right place to put high-speed digital signals
Interference to BPL • Our test conditions: Mobile Icom 706, with Outbacker Perth, curb side approximately 70ft from house, 100+ feet from the BPL pole interface. • BPL conditions: Output level was normal. System activity was low, however we had some control since we had access to a BPL modem and connection. Inside the home a laptop with BPL interface repeatedly downloading a 40MB+ file. • All Ham bands within the BPL spectrum were filtered out. Manassas, VA
Interference to BPL • Band Output Power Result • 80M 40w BPL data transfer stopped had to be restarted • 40M 40w and 2w BPL data transfer stopped had to be restarted • 20M 40w BPL data transfer stopped had to be restarted • 15M 40w BPL data transfer stopped had to be restarted • 10M 40w BPL data was interrupted or slowed. • We could not conclude testing all bands at all available power levels do to time constraints.
CA PUC • Public hearing on broadband deployment - including BPL – Draft Policy * Susan Kennedy • "encourage deployment of BPL by its electric utilities by providing regulatory certainty in the areas of its affiliate transaction rules, in the treatment of BPL program expenses and revenues, and exemption from Section 851 requirements for the use of utility assets."
CA PUC (cont.) • "should adopt this policy framework proactively without waiting for an application to be filed by an electric utility for a BPL project." • reply comments recommended the FCC "ensure that adequate testing is performed and industry standards are developed before any deployment takes place." The CPUC also noted "significant disagreement in the industry over the level of interference."
Dean Straw, N6BV at CA PUC • No mention of disadvantages • Interference to radio receivers • Interference from radio transmitters • No available bandwidth for expansion, especially where mitigation is required
CA PUC (cont.) • We (Hams) are not opposed to broadband internet services • We (Hams) are not opposed to BPL • We (Hams) are opposed to interference
CA PUC Reply Comments • Notwithstanding the Draft Report’s enthusiasm about Broadband over Power Lines (BPL), there is nothing to suggest that it will be a viable technological solution to broadband deployment hurdles any time soon.
CA PUC Reply Comments (cont.) • Even PG&E admits that while BPL may generate a multitude of benefits to both consumers and electricity and telecommunications utilities, it is “both density and distance-sensitive, and therefore, not presently well-suited to serve widely-dispersed rural users.”
Executive Summary • “Prescribing an anticipatory form of regulation could presume that we know how technologies and markets will evolve. Regulators also want to avoid favoring any one technology over others and thereby distort the market or impede innovation.”
BPL in WA • State Senate committee presentation • Chelan/Douglas – Main Net • Spokane – Avista – 2005? • Seattle City Light – evaluating various technologies
Good Signs • Many trial areas have shut down • Cedar Rapids, Iowa - deactivated by carrier after ham filed interference complaints. The carrier attempted to resolve the interference issues, but after 11 weeks or so, the interference was still unresolved. The FCC stepped in and the carrier voluntarily deactivated the system.
Good Signs • Penn Yan, New York - the system had open interference complaints, system integrator decided to discontinue the BPL trial and migrate to wireless. • Raleigh, North Carolina - Carrier announced deactivation of the system which they claim was a successful trial. Numerous interference complaints lodged, however, most of which were unresolved at the time of the announcement. It's arguable whether this shut down was due to interference, but the FCC never officially dismissed the interference complaints.
Good Signs • AT&T has withdrawn • Cisco is not funding Amperion’s continuing effort • Some utilities are working in cooperation with local Hams
New FCC Chair Kevin J. Martin’s statement at the 14 Oct. R&O • "Nevertheless, I recognize that Amateur radio operators still have concerns that they will experience interference from BPL systems. In addition, broadcasters are concerned that BPL systems will cause interference in the low VHF band. I take these concerns -- as well as the other concerns expressed about BPL systems causing interference -- very seriously. I am confident that the Commission will continue to monitor these concerns and will take steps, where needed, to address interference problems going forward."
What is ARRL doing? • Maintaining contacts and presence in standards area • Ed Hare is chair of IEEE C63 ad hoc BPL working group • Funding staff and outside filings • Funding staff and outside studies in BPL areas • Making other affected users aware of BPL interference issues and encouraging them to file • Articles in QST and on ARRL web pages • Guidance for local BPL teams
Reconsideration Petition • "a gross policy mistake.“ • "represents a classic case of prejudgment“ • deliberately authorizing "a spectrum pollution source“ • Powell "tainted this proceeding“ • "late and incomplete" responses to FOIA requests
What’s Next? • Circuit court of Appeals • Supreme Court
What Can You Do to Help? • Membership • Contributions to Spectrum Defense Fund • File comments with FCC • Right place at the right time
Good BPL • Microwave • 200 – 400 MHz
Other Technologies • WildBlue Satellite - 1st of 2 launched and will activate early 2005 – 35 spot beams 200 to 250 mi. dia. • Hughes Network Systems – 780 spot beams – 2005 • WiFi & WiMax • DSL – speed and distance improvements • Fiber to the Home
MORE INFORMATIONEd Hare, W1RFIARRL Laboratory Manager225 Main StNewington,CT 06111w1rfi@arrl.org860-594-0318 • http://www.arrl.org/bpl • http://www.rarchams.org/bpl.htm • http://www.arrl.org/~ehare/bpl/hyperlinks.html