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<<< Back to January 17 - Issue 197
January 24, 2000 - Issue 198Final Edition
- FCC Reaches Agreement on Use of 220-222 MHz, 24 GHz and 39 GHz Bands Along the U.S./Canada Border (Jan. 21)
- The FCC and Industry Canada have agreed on requirements for sharing the 220-222 MHz, 24 GHz and 39 GHz along the U.S.-Canada border. Operations in the 220-222 MHz band within 120 kilometers of the U.S-Canada border are affected by the interim Arrangement. The Arrangement allocates 200 channel pairs in the band for primary use by the United States, Canada or shared use by both and sets antenna height and power restrictions in the border area. There are special sharing arrangements for certain geographic areas and for low power stations. Affected U.S. licensees in the border area that have had their construction delayed during the negotiations were given a deadline of January 21, 2001 to construct base stations and place them in operation. See the Public Notice DA 00-109 for a summary of the Arrangement.
Broadband wireless systems in the U.S.-Canada border area operating in the 24.25-24.45 GHz, 25.05-25.25 GHz and 38.6-40.0 GHz frequency band are affected by another interim Arrangement. In this Arrangement, licensees on both sides of the border are encouraged to develop their own cross-border sharing agreements. If licensees cannot develop their own agreements, the Arrangement specifies certain "power flux density" (pfd) levels and imposes different coordination requirements depending on the pfd level involved. Operations below are certain pfd level require no coordination. This information is from FCC News Release (nrin0003).
The full text of the both Arrangements are available in Adobe Acrobat format from the FCC International Bureau Planning and Negotiations Division International Agreements web page.
- FCC Seeks Comment on Computer Model Predicting Signal Intensity to Determine Unserved Households (Jan. 20)
- The FCC has released a Notice of Proposed Rule Making seeking comments on the computer model it uses to predict signal intensity at a household for purposes of determining eligibility for receiving distance TV broadcast signals by satellite. The Individual Location Longley-Rice (ILLR) computer model was created in the FCC's February 1999 Satellite Home Viewer Act (SHVA) Report and Order. In the Order, the FCC asked the cable and broadcast industries for guidance on how to include vegetation and buildings in the model.
The Satellite Home Viewer Improvement Act enacted by Congress last November recognized the FCC's ILLR and directed the FCC to revise it to include "terrain, building structures and other land cover variations." The FCC proposes to meet this requirement by adding clutter loss parameters. The NPRM states: "Reception point environments are to be classified in terms of the codes used in the Land Use and Land Cover (LULC) database of the United States Geological Survey, and clutter loss values are to be added to the radio propagation loss predicted by basic Longley-Rice 1.2.2. Based on therecord in CS Docket No. 98-201, we believe the LULC database is highly appropriate for incorporating land use and clutter in ILLR. The LULC database is publicly available in a form suitable for use in conjunction with computer programs at the point-of-sale of satellite programming services."
The technical details of the ILLR analysis are outlined in Appendix A of the NPRM. Table 3 of Appendix A specifies clutter loss values in dB to added to the Longley-Rice prediction of path loss. Loss values range from 0 dB over wetland, water and snow and ice to 25 dB on UHF channels 38-69 in forested areas. This example points out the difference frequency makes in clutter loss. In the forest environment, loss at channels 2-6 is 7 dB. At channels 7-13 it is 8 dB. For UHF channels 14-36 the loss is 16 dB but for channels 38-69 the loss increases to 25 dB. For the high-UHF channels, the loss is greater in residential areas (21 dB) than in mixed urban areas (16 dB). For low-UHF channels, loss is 1 dB greater in mixed urban areas (17 dB) and 3 dB less (18 dB) in residential areas.
The LULC database is available at http://edcwww.cr.usgs.gov/glis/hyper/guide/1_250_lulc. A summary of the NPRM is available in the FCC News Release FCC Seeks Comment on Computer Model Predicting Signal Intensity to Determine Unserved Households. The Notice of Proposed Rule Making on Establishment of an Improved Model for Predicting the Broadcast Television Field Strength Received at Individual Locations, ET Docket No. 00-11,
is available for download from the FCC web site as a text file (fcc00017.txt) or Word 97 document (fcc00017.doc). Note that the table format in the text version may be difficult to interpret. Also see the FCC Satellite Home Viewer Improvement Act Page.
- FCC Approves New Non-Commercial Low Power FM Radio Service (Jan. 20)
- The FCC issued a News Release (nrmm0001) announcing the creation of a new non-commercial low-power FM radio service. Stations under the LPFM service are divided into two classes - LP100, with a power from 50-100 watts and a service radius of about 3.5 miles and LP10, with a power from 1-10 watts and a service radius of about 1-2 miles. Interference to existing FM broadcast services will be limited by using distance separations between co-channel, 1st-adjacent, 2nd-adjacent and intermediate frequency (IF) related stations.
Stations will be required to broadcast a minimum of 36 hours per week. During the first two years of the service, no entity will be permitted to operate more than one LPFM station nationwide. The News Release said "no existing broadcaster or other media entity can have an ownership interest, or enter into any program or operating agreement, with any LPFM Station." LPFM stations will be prohibited from operating as translators. The News Release said " Eligible licensees can be noncommercial government or private educational organizations, associations or entities; non-profit entities with educational purposes; or government or non-profit entities providing local public safety or transportation services." Although the stations will be non-commercial, licenses will not be limited to the FM frequencies reserved for use by non-commercial educational stations.
The News Release contains a link to a zip file with the full text of the Order in Word format. Also see the FCC LPFM website.
- DTV - Proposed Canadian DTV Letter of Understanding Impacts DTV Maximization Near U.S. Canadian Border (Jan. XX)
- The engineering consulting firm of Hammett and Edison posted a copy of a Letter of Understanding Between the Federal Communications Commission and Industry Canada Related To the Use of the 54-72 MHz, 76-88 MHz, 176-216 MHz and 470-806 MHz Bands For the Digital Television Broadcasting Service Along the Common Border. The Letter of Understanding (LOU) applies to proposed facilities located within 400 km (249 miles) of the U.S-Canada border. Low power television facilites, either digital or analog, proposed within 100 km (62 miles) of the border are included in the LOU. Major U.S. TV markets that fall under this LOU include Chicago, Boston, Baltimore, Detroit, Minneapolis, New York City, Cincinnati, Cleveland, Portland OR, Philadelphia, Seattle,and Milwaukee as well as many others. Some of the Canadian markets included are Calgary, Regina, Vancouver, Winnipeg, Moncton, Saint John, Halifax, Yarmouth, Ottawa, Toronto, Montreal, and Quebec.
Under Appendix 3, Planning and Separation Criteria, of the LOU, DTV service availability is based on F90/90 availability (90 percent of the locations 90 percent of the time), except during the analog to digital transition period when F50/90 criteria is used. The minimum required signal strength is 35 dBuV/m at low-VHF, 33 dBuV/m at high-VHF and 39 dBuV/m at UHF. (The "u" in dBuV/m refers to the prefix "micro"). Appendix 3 includes several cases where co-channel stations (both VHF and UHF) located over 300 km apart would have to conduct additional interference studies. All proposed allotments in Canada and the U.S. (as outlined in the FCC 98-315 Table of DTV Allotments) were accepted, although the LOU notes that "in a few cases, acceptance was based on adjustments noted in the Plan." In one case, the entry for DTV channel 34 in Buffalo NY includes the comment: "-20 dB to 34D Peterborough ON". If a station desires to modify its facility, approval under the LOU would be required if the parameters proposed exceed those in the plan. The LOU states: "Parameters include ERP, HAAT, location, and, if a directional antenna is used, its pattern in the horizontal plane. Parameters are deemed to exceed those in the Plan if the pertinent interfering contour extends further into the other country."
The LOU sets specific deadlines for approval of DTV allotments. If the proposed parameters do not exceed those in the plan, the other country must be notified, the parameters are considered approved, and operation may begin 21 days after the notification is sent. If the proposed parameters exceed those in the Plan but meet the spacing requirements of Appendix 3, notification is also required, and the parameters will be considered approved if the affected Administration objects and states the reason for the objection with 21 days of the date the notification is sent. "Discussions to resolve the situation shall follow." If the proposed parameters exceed those in the plan and do not meet the spacing requirement, notification is required and a study using the Longley-Rice propagation model must be included with it. Before operation can begin, a favorable response is required or, if no response is received within 45 days from receipt of the notification, it will be assumed the notification has been approved. If the notification is rejected, the reasons for the rejection must be stated. Other requirements exist for allocations not included in the plan and low-power analog or digital stations.
Hammett and Edison prepared a list of U.S. DTV allocations short-spaced with respect to Canadian allotments. Before these stations can modify their FCC DTV allotment from that contained in the Plan (usually the same as in the last FCC DTV Table of Allotments), a Longley-Rice study must be included with the Canadian notification. A copy of the Letter of Understanding and the listing of short spaced DTV allocations is available on the Hammett and Edison web site in Adobe Acrobat format.
- OTHER Items of Interest
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