Frequencies in the VHF and UHF Bands for Use as "Wide Area" Channels and "Common Use" Channels

United States Department of Commerce
National Telecommunications and Information Administration
Interdepartment Radio Advisory Committee
Washington, D.C. 20230

6110-7
6110-26

July 27, 1978

Director, Telecommunications Regulation Branch
Telecommunication Regulatory Branch
Journal North Building
300 Slater Street
Ottawa, Ontario
K1A 0C8

Dear Sir:

NTIA has recently allotted two sets of frequencies in the VHF and UHF bands to be reserved for use as "wide area" channels and "common use" channels.

163.100, 418.050 and 418.575 MHz have been allotted as wide area channels to provide for intermittent wide area requirements of a transient nature. It is envisioned that many of these assignments will be U.S. wide. It occurs to us that Canada probably has the same type of requirement to be able to use a frequency anywhere in Canada on a short term basis. If you are in a position to do so, you might want to consider a similar allocation for these frequencies in Canada.

168.350, 408.400 and 418.075 MHz have been allotted as common use frequencies to provide for radiocommunications that do not justify the assigning of a radio frequency exclusively to that use i.e., the frequency can be shared with other users. It is intended that there will be multiple users of these frequencies within interference range but the nature of the frequency use would allow sharing of the channel. Hopefully, Canada has a requirement for a complement of frequencies to meet low priority or low duty cycle frequency requirements that could be satisfied using one of these frequencies on a shared non-priority basis.

Attached are the rules we have established for use of both categories of use. We would appreciate your comments on the possibility of Canada using these frequencies in the same manner or if this is not possible, comment on our use of 163.100 MHz as a "wide area channel" U.S. wide. In the light of no formal coordination agreement for the 410–420 MHz band, any comments you have on our use of 418.050 and 418.575 MHz as wide area channels would also be appreciated. If Canada has no requirement for common use channels, we would continue to coordinate our use of 168.350 MHz as we have been under Arrangement D.

A. M. Corrado
Executive Secretary

Attachments


Attachment 1

4.2.3 Allotment of 163.100, 418.050, and 418.575 for Wide Area Use

These allotments are to provide for intermittent wide area requirements of a transient nature. The frequencies 163.100, 418.050, and 418.575 MHz are allotted for use by U.S. Government agencies and may be authorized for use by agencies as required upon application.

The designed frequencies are available on a shared non-priority basis only and will not be authorized for exclusive use of any one agency. No protection from interference will be provided to any station operating on these frequencies from other stations operating on the same frequency. The use of equipment with coded squelch is strongly encouraged to reduce interference from other users.

In all cases, the minimum ERP necessary to support the intended use shall be employed. However, the maximum transmitter output power of the base station shall not exceed 30 watts and the mobile output power shall not exceed 30 watts. The gain of the base station antenna shall not exceed 7 decibels and the height of the base station antenna shall not exceed 20 feet above the height of the structure containing the transmitting equipment. The station class is limited to FB, FC, ML or MS and portable fixed (FX, S016). All equipment shall be in conformity with 5.4 of the Manual. Repeater operations are not permitted.

All applications for the use of these frequencies must bear record note S352 which reads, "This assignment is for intermittent wide area requirements of a transient, itinerant nature pursuant to Section 4.2.3 of the Manual."


Attachment 2

4.2.4 Allotment of 168.350, 408.400 and 418.075 MHz as Common Use Frequencies

These allotments are to provide for radiocommunications that do not justify the assigning of a radio frequency exclusively to that use i.e., the frequency can be shared with other users.

The frequencies 168.350, 408.400 and 418.075 MHz are allotted for use by U.S. Government agencies and may be authorized for use by agencies as required upon application. All operations shall be authorized in accordance with Section 9.1.3. The frequencies are available on a non-priority basis only and will not be authorized for the exclusive use of any one agency. No protection from interference will be provided to any station operating on these frequencies from other stations operating on the same frequency. Critical services involving safety of life and property should not employ these frequencies in view of their unprotected status. The use of equipment with coded squelch is strongly encouraged to reduce nuisance interference from other users.

In all cases, the minimum ERP necessary to support the intended use shall be employed. However, the maximum transmitter output power of the base station shall not exceed 30 watts and the mobile output power shall not exceed 30 watts. The gain of the base station antenna shall not exceed 7 decibels and the height of the base station antenna shall not exceed 20 feet above the height of the structure containing the transmitting equipment. The station class is limited to FB, FC, ML or MS and portable fixed (FX, S016). All equipment shall be in conformity with 5.4 of the Manual. Repeater operations are not permitted.

All applications for the use of these frequencies must bear record note S353 which reads "This assignment is for a common use frequency pursuant to Section 4.2.4 of the Manual."


Journal Tower North
300 Slater Street
Ottawa, Ontario
K1A 0C8

6110-7 (DOS-F2)
6110-26

January 17, 1979

Executive Secretary
Interdepartment Radio
Advisory Committee (IRAC)
1325 G Street, N.W.
Suite 250
Washington, D.C. 20005
U.S.A.

Dear Sir:

This has reference to your letter of July 27, 1978, requesting our comments on the NTIA allotment of two sets of frequencies in the VHF and UHF bands for use as "wide area" channels and "common use" channels throughout the U.S.

Your proposal has been examined in light of possible similar Canadian requirements. We have concluded that the NTIA concept is a good one and certainly would enhance the processing of frequency assignments intermittent or transient in nature involving short-term "temporary" applications. A mutual Canada/U.S. arrangement on common frequencies would of course, offer maximum practical advantages in the border areas.

The frequencies listed in your letter have been evaluated for compatibility with the existing Canadian ECM environment and actual requirements and we are able to say that "common use" of the UHF frequencies appears to be practical. With regard to the VHF frequencies, however, the rather extensive use of these frequencies in Canada would preclude their use as proposed as well as their "uncoordinated" use.

Our specific comments relative to the frequencies in question are as follows:

  • 163.100 MHz and 168.350 MHz — No objections, subject to favourable U.S./Canada Coordination;
  • 408.400 MHz — No objections on a non-interference basis. This frequency is used in Canada exclusively for radio astronomy purposes;
  • 418.050 MHz, 418.075 MHz — Agree, common U.S./Canada usage on a shared 418.575 MHz non-priority basis.

While we have not formulated any firm policy as yet on the condition of assignment of the UHF frequencies, we envision that restrictions on frequency use similar to those adopted in the U.S. will be implemented. We regret the delay in responding to your letter which was unavoidable due to national coordination requirements.

Yours very truly,

Dr. John deMercado
Director General
Telecommunication
Regulatory Service

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