Coordination and Use of 25 kHz Frequency Assignments in the Aeronautical Mobile (R) Sub-band 128.8125-132.0125 MHz

Federal Communications Commission
Washington, D.C. 20554

In reply refer to: 6320-C

September 27, 1977

Mr. M.F. Yalden
Deputy Minister of Communications
Department of Communications
Ottawa, Ontario
K1A 0C8
Canada

Dear Mr. Yalden:

Pursuant to meetings held in Ottawa, Canada on February 28, 1977 and in Washington, D.C. on May 18-20, 1977, between representatives of the Canadian Department of Communications and the United States Federal Communications Commission on the subject of the coordination and use of 25 kHz frequency assignments in the aeronautical mobile (R) sub-band 128.8125-132.0125 MHz, the attachments are recommended interim procedures to be utilized by the two governments pending revision of the Agreement Between the United States of America and Canada on the Coordination and Use of the Radio Frequencies Above 30 Megacycles per Second.

We are pleased to advise that these procedures have been approved by the Commission and recommend that they become effective upon the date of your written acceptance.

This letter was adopted by the Commission on September 14, 1977.

BY DIRECTION OF THE COMMISSION

Richard E. Wiley
Chairman

Attachments - 3


December 20, 1977

Mr. Charles D. Ferris
Chairman
Federal Communications Commission
1919 M Street, N.W.
Washington, D.C. 20554
U.S.A.

Dear Mr. Ferris,

This refers to the Commission's letter of September 27, 1977 on the subject of the coordination and use of 25 kHz frequency assignments in the aeronautical mobile (R) sub-band 128.8125-132.0125 MHz and which included attachments which are recommended interim procedures to be utilized by the two governments pending revision of the Agreement Between the United States of America and Canada on the Coordination and Use of the Radio Frequencies Above 30 Megacycles per Second.

Whilst we can agree to the intent of the agreement, we feel that its comprehension would be enhanced by a rearrangement of the order of the paragraphs as per the attachment to this letter.

On the assumption that this minor adjustment would be acceptable to the Commission, we are pleased to advise that these procedures have been approved by this Department and have become effective as of this date.

Yours sincerely,

André Lapointe
Acting Deputy Minister


Federal Communications Commission
Washington, D.C. 20554

In reply refer to: 6320-C

February 14, 1978

Mr. André Lapointe
Acting Deputy Minister
Department of Communications
300 Slater Street
Ottawa, Ontario
K1A 0C8

Dear Mr. Lapointe:

This refers to your response of December 20, 1977 to our letter of September 27, 1977, relating to the establishment of interim procedures for the coordination and use of 25 kHz frequency assignments in the aeronautical mobile (R) sub-band 128.8125-132.0125 MHz.

We have noted your approval of these procedures with the minor adjustments in the order of the paragraphs as shown in the attachment to your letter. We find these adjustments acceptable and are therefore pleased to consider the interim procedures to be in effect between our respective administrations as of the date of this letter.

I wish to extend my appreciation for the excellent cooperative spirit which prevailed during the development of the procedures and am sure that this arrangement will greatly facilitate our spectrum management responsibilities in this band.

Sincerely,

Charles D. Ferris
Chairman


Attachment 1

U.S.A./Canada Interim Channeling Arrangement for the Aeronautical Mobile (R) / (Enroute) Service Utilizing 25 kHz Channels for the Band 128.8125-132.0125 MHz

  1. The provisions of this Arrangement apply to Canada and the United States in the utilization of the 25 kHz channels for the band 128.8125-132.0125 MHz which appear in paragraph 2 below.
  2. These 25 kHz channels are allotted as follows:

    U.S.A./Canada Interim Channeling Arrangement for the Aeronautical Mobile (R) / (Enroute) Service Utilizing 25 kHz Channels for the Band 128.8125-132.0125 MHz
    Freq. MHz U.S.A. Canada
    128.825 x
    .875 x
    .925 x
    .975 x
    129.025 x
    .075 x
    .125 x
    .175 x
    .225 x
    .275 x
    .325 x
    .375 x
    .425 x
    .475 x
    .525 x
    .575 x
    .625 x
    .675 x
    .725 x
    .775 x
    .825 x
    .875 x
    .925 x
    .975 x
    130.025 x
    .075 x
    .125 x
    .175 x
    .225 x
    .275 x
    .325 x
    .375 x

    U.S.A./Canada Interim Channeling Arrangement for the Aeronautical Mobile (R) / (Enroute) Service Utilizing 25 kHz Channels for the Band 128.8125-132.0125 MHz
    Freq. MHz U.S.A. Canada
    130.425 x
    .475 x
    .525 x
    .575 x
    .625 x
    .675 x
    .725 x
    .775 x
    .825 x
    .875 x
    .925 x
    .975 x
    131.025 x
    .075 x
    .125 x
    .175 x
    .225 x
    .275 x
    .325 x
    .375 x
    .425 x
    .475 x
    .525 x
    .575 x
    .625 x
    .675 x
    .725 x
    .775 x
    .825 x
    .875 x
    .925 x
    .975 x

    Note 1: Frequencies primarily allotted for United States use may also be assigned to Canadian stations within the frequency coordination zones listed in Attachment 2 following successful coordination with the United States.

    Note 2: Frequencies primarily allotted for Canadian use may also be assigned to United States stations within the frequency coordination zones listed in Attachment 2 following successful coordination with Canada.

    Note 3: All frequencies listed in paragraph 2 may be assigned without prior coordination outside the coordination zones listed in Attachment 2.

    Note 4: Both frequency plans will remain in effect until the Canada/U.S. Allotment Plan mentioned in paragraph 7 of the interim agreement becomes effective.

    Note 5: The frequency band 131.4 and 132.0 MHz is being protected to the extent practicable, in Canada for the duration of the Aerosat experiments scheduled to begin in 1980. The Aerosat experiments will employ 25 kHz channels which are compatible with the interim agreement.

    Note 6: It is unclear whether DIC means non-conforming 25 kHz equipment of broadband (50 and 100 kHz) equipment. As mentioned in TRC-41 25 kHz equipment will be evaluated for technical acceptance in keeping with established procedures. This would seem to preclude the putting into service of "non-conforming" 25 kHz equipment.

    Note 7: 50/100 kHz users operating after 1981 will not be protected from interference from properly operating 25 kHz assignments nor in the coordination process, a conflicting 25 kHz channel would not normally be assigned unless there are no other 25 kHz channels available in the area. DIC's reference to paragraph 6, page 3, of interim arrangement re conforming and nonconforming systems is not clear.

    Note 8: Status of existing allotted channels after 1981

    Insofar as coordination between both countries is concerned, both plans are effective until a new Agreement is signed. However, after February 1, 1981, broadband assignments will no longer be protected in the coordination process from implementation of properly operating 25 kHz channels. TRC-41 recognizes the desirability of domestically assigning only 25 kHz channels after February 1, 1981, for operation in the 128-132 MHz band. All VHF Aero mobile communication bands will likely adopt a 25 kHz plan by the mid or late eighties.

  3. Frequencies proposed for assignment in accordance with paragraph 2 above, which will be located within 25 NM of the U.S./Canada border, shall be coordinated with the other Administration prior to implementation. Requests for frequency assignments removed 25 kHz from existing assignments listed in Attachment 3 will be coordinated when such an assignment will be within 130 NM of the existing station. With these exceptions frequencies may be assigned and stations established by either country in accordance with paragraph 2 without coordination with the other country.
  4. In adopting the above Arrangement, it is understood that each Administration has complete flexibility in making use of its channels within the frequency coordination zone; that the option provided by Notes  1) and 2) should not be exercised unless the proposed assignment cannot be accommodated on a channel allotted under the plan; that an assignment made under the provisions of Notes 1) and 2) should not be a bar to future utilization of the channel by the Administration to which it is allotted under this Arrangement. However, in the event that return of a frequency is deemed necessary by the Administration to which it is allotted in paragraph 2 above, consideration shall be given to the overall frequency utilization in the area of the proposed station. Before an Administration requests the return of one of its allotted frequencies, it shall establish that it cannot otherwise meet its operational requirements. Where a determination indicates congestion of equal magnitude, consideration should be given to the sharing of a frequency on an equal basis by the two countries. In cases where such determination indicates greater congestion in the area of the proposed station, the frequency shall be returned to the Administration to which the channel is allotted.
  5. In order to ensure protection of the Air Traffic Control frequencies 128.8 and 132.025 MHz, the assignment of the frequencies 128.825 and 131.975 MHz within 600 NM of the U.S./Canada border are subject to prior coordination with the other Administration.
  6. Implementation of 25 kHz channel assignments by either Administration shall become effective on the date of signing of Letters of Understanding by both the United States and Canada. The use of 50 and 100 kHz equipments shall not be protected from properly operating 25 kHz equipments beyond February 1, 1981.
  7. This Arrangement, which is subject to periodic review at the request of either Administration, is of an interim nature pending its incorporation into an Allotment Plan for certain bands allotted to the aviation services to meet the United States and Canadian aeronautical frequency requirements along the U.S./Canada border, to the mutual satisfaction of both countries.

Attachment 2

Frequency Coordination Zones For Co-Channel Assignments
Type of Station Altitude Level
(Feet)
Coordination Zone
(Nautical Miles)
Ramp (RT) Ground Level 50
Helicopter (HO) 0 to 2,000 150
Low Level (LL) 0 to 10,000 250
Mid Level (ML) 0 to 20,000 400
High Level (HL) Over 20,000 600

In Attachment 2, there are three maps which portray the Canada-United States frequency coordination zones for co-channel assignments.

Figure 1: Map of Alaska

Map of Alaska (the long description is located below the image)
Description of Figure 1

For the first map, the State of Alaska is depicted showing the different coordination zone distances by a series of lines, dependent on type of station, from the Yukon-Alaska border. Ramp operation is shown at 50 nautical miles; helicopter at 150 nautical miles; low-level at 250 nautical miles; medium-level at 400 nautical miles; and high-level at 600 nautical miles.


Figure 2: Map of the United States

Map of the United States (the long description is located below the image)
Description of Figure 2

The second map depicts the lower 48 states of the continental United States with the corresponding coordination zone distances for ramp, helicopter, low-level, medium-level and high-level operations.


Figure 3: Map of Canada

Map of Canada (the long description is located below the image)
Description of Figure 3

The third map depicts Canada with its corresponding coordination zone distances for ramp, helicopter, low-level, medium-level and high-level operations.


Attachment 3

US 25 kHz Assignments will be Coordinated with Canada when Adjacent To and Within 130 NM of the Existing 50 kHz Canadian Assignments Listed Hereunder

US 25 kHz Assignments will be Coordinated with Canada when Adjacent To and Within 130 NM of the Existing 50 kHz Canadian Assignments Listed Hereunder
Location Frequency (MHz)
Abbotsford, B.C. 129.25
130.8
Burnaby, B.C. 130.0
Delta, B.C. 128.85
130.35
Saltspring Island, B.C. 130.5
Vancouver, B.C. 129.25
129.35
129.9
130.8
130,9
131.2
Victoria, B.C. 129.2
130.6
Fort Frances, Ont. 130.15
Sarnia, Ont. 130.35
Sault Ste. Marie, Ont. 130.15
130.9
St. Catharines, Ont. 131.1
Windsor, Ont. 131.1
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