RPR-2 — Règles et procédures de demande relatives aux entreprises de radiodiffusion AM

B-4. Preliminary Proof of Performance for Directional Antennas

It is recognized that the surveys and calculations necessary for a Final Proof of Performance may take considerable time. For this reason, the Department will normally accept a Preliminary Proof of Performance for the purpose only of permitting the station to commence operation, provided that the Final Proof of Performance is submitted within 90 days.

B-4.1 Documentation

The Preliminary Proof of Performance (in quadruplicate) shall be submitted to the Director, Broadcast Applications Engineering, at least five working days before commencement of regular broadcasting. It shall consist of:

proof of the shape of the pattern determined from field strength measurements taken at a convenient⁵ distance from the transmitter at approximately 15° intervals, by means of ratio between the directional pattern and non-directional operation, or by any other acceptable method such as short radials if a reliable non-directional pattern is not available;
proof of the size of the pattern by means of a series of readings along one radial in a major lobe to a distance of at least 16 km. The approximate effective field at one kilometre, the attenuation curve and the mean conductivity for the region, shall be determined from these readings;
antenna operating impedances (Z = R + jX) for each tower and pattern at carrier frequency and the antenna self-impedances for each tower measured at carrier frequency and in 10 kHz steps over the range of ±30 kHz.

Where protection to other stations on the same or adjacent channels is required, additional measurements shall be supplied to show that interference will not result from the operation of the station for which the proof of performance is being made.

B-4.2 Tolerance

The normal upper limit is the expanded pattern and the normal lower limit is 5% below the theoretical pattern. Any deviation beyond these limits should be justified. Also, if the upper limit is exceeded but this would not lead to interference, the pattern may be modified in accordance with Annex 2, Appendix 3 of Canada/USA Agreement, 1984. The upper limit may not be exceeded if interference would result.

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B-5. Final Proof of Performance for Non-Directional Antennas

The installation is deemed to be incomplete until such time as the Final Proof of Performance of the antenna system has been submitted to the Director, Broadcast Applications Engineering, and approved by the Department.

B-5.1 Documentation (in quadruplicate)

A proof of performance demonstrating the inverse distance field strength in terms of millivolts per metre at a distance of one kilometre is required of all broadcasting stations operating with non-directional antennas.

Field strength contours are required to show the actual coverage of the station, although the contour protected against interference from other stations is that calculated in accordance with Annex 2, Chapter 2 of Canada/USA Agreement, 1984 and for stations in the 1605-1705 kHz band, with Section C-6, unless there is specific agreement between the stations involved.

The following are the data which shall be submitted in the proof of performance, together with a description of the procedure to be followed in obtaining these data.

B-5.2 Field Strength Measurements to Establish the Effective Field Strength at One Kilometre for Class A or B Stations

Beginning as near to the antenna as possible without including the induction field and to provide for the fact that a broadcast antenna is not a point source of radiation (not less than one wavelength or five times the vertical height), measurements shall be made on eight radials at intervals of approximately:

200 metres up to 3 kilometres from the antenna;
one kilometre from 3 to 10 km from the antenna;
and 3 kilometres beyond 10 km, as required.

Where unobstructed measurements can be made, there should be 18 or more on each radial. However, where unobstructed measurements are difficult to make, these shall be made on each radial at as many unobstructed locations as possible, even though the intervals are considerably less than stated above, particularly within five kilometres of the antenna. In cases where it is not possible to obtain accurate measurements at the closer distances (even out to 8 or 10 km due to the character of the intervening terrain), the measurements at greater distances should be made at closer intervals.

The measurement data shall be plotted for each radial using log-log coordinate paper with field strength as ordinate and distance as abscissa.

The appropriate curve to be drawn through the points plotted shall be determined by comparison with theoretical curves as follows:

plot theoretical curves (refer to Appendix 2, Annex 2 of the Canada/USA Agreement, 1984 and Annex 1, Chapter 2 of Rio 1988 Agreement) for several values of conductivities approximating the conductivity indicated by the measurements on another sheet of the same coordinate paper;
place this sheet under the sheet on which the actual points have been plotted and adjust until the curve most closely matching the points is found;
draw this curve on the sheet on which the points were plotted, together with the inverse distance curve corresponding to that curve.

The field at one kilometre for the radial concerned shall be the ordinate on the inverse distance curve at one kilometre.

When all radials have been analyzed in this manner, a curve shall be plotted on polar coordinate paper from the fields obtained, which gives the inverse distance field pattern at one kilometre. The radius of a circle, the area of which is equal to the area bounded by this pattern, is the measured effective field.

While making the field strength survey, the output power of the station should be maintained at the licensed power as determined by the direct method. If a lower power is used, the results of measurements should be adjusted appropriately. Therefore, it is necessary to determine the antenna impedance as accurately as practical, and to measure the antenna current by means of an ammeter of known accuracy.

Complete data taken in conjunction with the field strength measurements shall be submitted, including the following:

tabulation by number of each point of measurement, the field strength and the distance from the antenna for each point of measurement;
map(s) showing each point of measurement numbered to agree with the tabulation required in (a) above;
curves drawn for each radial showing the field strength as a function of distance;
antenna self impedance (Z = R + jX) at carrier frequency and in 10 kHz steps over the range ±30 kHz, and the results presented in tabular as well as graphical forms;
antenna current (day and night) maintained during field strength measurements;
any other pertinent information.

B-5.3 Field Strength Measurements to Establish the Effective Field Strength at One Kilometre for Class C Stations

The procedure for establishing the effective field strength at one kilometre for Class C stations or stations in the 1605-1705 kHz band, shall be the same as in Section B-5.2 above except that measurements may be made on two radials only, and need not extend beyond the 0.5 mV/m contour.

B-5.4 Test Equipment and Qualifications

The following information shall be submitted on the equipment used for the measurements and on the qualifications of the person responsible for the measurements:

description, accuracy, date and by whom each instrument was last calibrated;
name, stamp and signature of the engineer responsible for the measurements.

B-5.5 Plot of Field Strength

The measured field strength contours should be presented in the same format as in Section B-2.9.

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B-6. Preliminary Proof of Performance for Non-Directional Antennas

The surveys and calculations necessary for a Final Proof of Performance may take considerable time. The Department will normally accept a Preliminary Proof of Performance for the purpose only of permitting the station to commence operation, provided that the Final Proof of Performance is submitted within 90 days.

B-6.1 Documentation

The Preliminary Proof of Performance shall be submitted to the Director, Broadcast Applications Engineering, at least three working days before commencement of regular broadcasting and shall consist of:

a tabulation by number (at least 10) of each point of measurement of the field strength taken along one radial to establish with reasonable accuracy the inverse distance field strength in mV/m at one kilometre;
distances from the antenna of all measurement points included in the tabulation required in (a) above;
a plot of the measurements as required in Section B-5.2 with the unattenuated field at one kilometre indicated thereon.

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B-7. Supplementary Proof of Performance (SPOP)

B-7.1 Introduction

Broadcasting stations are required at all times to protect other stations from interference, as prescribed by international agreements and domestic requirements. Therefore, it is imperative that the operation of broadcast transmitters and their antenna systems be checked from time to time. Accordingly, an SPOP shall be submitted, upon request by the Industry Canada, normally every five years after submission of the previous supplementary or final proof. The SPOP shall be submitted to the departmental office that requested it. SPOPs of performance are not required for non-directional antenna systems.

In addition to normal monitoring, the following comprise the requirements for an SPOP to demonstrate that the broadcast antenna system continues to function as authorized.

B-7.2 Measurements

B-7.2.1 The shape of the directional pattern shall be determined from field strength measurements taken at a convenient distance from the transmitter at approximately 15 degree intervals by means of the ratio between the directional pattern and non-directional operation, or by any other acceptable method such as short radials if a reliable non-directional pattern is not available.

B-7.2.2 The size of the pattern shall be determined by means of a series of field strength measurements taken in a major lobe along one radial from approximately 200 metres from the antenna to a distance of 16 km or to the 0.5 mV/m contour whichever is closer. The effective field at one kilometre shall be determined from these readings as set forth in Section B-3.3.

B-7.2.3 Impedance characteristics of the radiating elements and the operating impedance at point of common input shall be determined by the direct method and expressed as Z = R + jX.

B-7.2.4 To determine the unattenuated field strength at one kilometre, the field strength measurement data should be plotted on log-log coordinate paper with field strength as ordinate and distance as abscissa. The appropriate curve to be drawn through the points plotted shall be determined by comparison with theoretical curves as follows:

plot theoretical curves (refer to Appendix 2 of the Canada/USA Agreement, 1984 and Annex 1, Chapter 2 of Rio 1988 Agreement) for several values of conductivities approximating the conductivity indicated by the measurements on another sheet of the same coordinate paper;
place this sheet under the sheet on which the actual data points have been plotted and adjust until the curve most nearly matching the points is found;
draw this curve on the sheet on which the points were plotted.

The field at one kilometre for the radial shall be the ordinate on the inverse distance curve at one kilometre.

B-7.2.5 While making the field strength measurements, the output power of the station should be maintained at the licensed power as determined by the direct method. A careful log shall be taken of the operating parameters during the measurement period.

B-7.3 Documents

A Supplementary Proof of Performance shall comprise the following, prepared or approved by a professional engineer and submitted over the engineer's stamp and signature:

a statement of the work which was done, adjustments made, components replaced, measurements taken and instructions left with operating staff;
a polar plot of the measured pattern and the expanded (or modified, if applicable) directional antenna pattern (see B-2.5.3 for guidelines);
a plot of the field strength measurements made along the single radial, together with the inverse distance curve plotted on suitable log-log graph paper. The values of ground conductivity and field strength at one kilometre shall be marked;
information on the antenna impedance measurements shall be provided showing:
- description of the methods employed;
- measurement data;
- impedances of each tower at the operating frequency expressed as Z = R + jX;
a table of current and phase readings of the transmitter and antenna system as finally adjusted and the transmitter output efficiency;
if other work was done at the transmitter, such as adjustment and calibration of supervisory control equipment, frequency or modulation monitors, proper documentation covering this work should also be included.

B-7.4 Tolerance

The normal upper limit is the expanded pattern and the normal lower limit is 5% below the theoretical pattern. Any deviation beyond these limits should be justified. Also if the upper limit is exceeded but this would not lead to interference, the pattern may be modified in accordance with Annex 2, Appendix 3 of Canada/USA Agreement, 1984. The upper limit may not be exceeded if interference would result.

B-7.5 Test Equipment and Qualifications

The following information shall be submitted on the equipment used for the measurements and on the qualifications of the person responsible for the measurements:

description, accuracy, date and by whom each instrument was last calibrated;
name, stamp and signature of the engineer responsible for the measurements.

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B-8. Applications for Low-Power Unprotected Stations and Carrier Current Systems with Transmitter Powers of less than 100 W

B-8.1 Low-Power Unprotected Broadcasting Stations

Normally, an application for a low-power unprotected broadcasting station is technically acceptable if:

no interference to other stations is predicted, using regular protection criteria;
the signal level within the area to be served is sufficient to provide reliable daytime and nighttime services;
the disparity between day and night service is minor, i.e., the E_u contour shall enclose at least 90% of the population within the 0.5 mV/m contour.

The transmitter should meet Broadcasting Equipment Technical Standard No. 5 (BETS-5). The use of a transmitter which does not meet these standards could result in an inadequate quality of service.

B-8.1.1 Requirements for an Application

The requirements for an application for a low power broadcasting station are:

one copy of Form IC-3051A as applicable;;
one copy of Form IC-3052B;
one copy of an engineering brief.

Normally, an engineering brief need only describe the transmitting plant and location (population to be served, audio feed). However, if the Department's analysis indicates that protection or service requirements may not have been met, a detailed engineering submission may be requested.

With regard to locating the antenna site, please refer to Section B-1.1.3.

B-8.2 Carrier Current Systems

Normally, an application for carrier current system is considered technically acceptable if the technical requirements of the Department are met as set forth hereafter.

B-8.2.1 Requirements

An engineering brief containing the following data shall be submitted to the Department:
- the location of the transmitter;
- the proposed frequency;
- the type of equipment to be used (manufacturer's name, model number, power). This equipment should be approved by Industry Canada.
Such apparatus will deliver to the line network the minimum radio frequency power necessary to accomplish the desired purpose.
No interference is expected to be caused to other radio services.

B-8.2.2 Proof of Performance and Certification Requirements

A proof of performance demonstrating that the installation meets the requirements mentioned below, shall be submitted to the Director, Broadcast Applications Engineering, at least five working days before the desired date for regular operation.

The applicant shall provide evidence that the electromagnetic field extending outside the property to be served containing the signal distribution circuit does not exceed 15 uV/m at a distance

d=48,000/f

d = the distance in metres
f = the frequency in kHz

from the property served. The measurements shall be taken in daylight using a field strength meter operated by an engineer or technician experienced in this work. The readings shall be obtained with the antenna not less than 50 cm nor more than three metres above ground at 12 points spaced as equally as may be practicable around the property at or within the required distance d.

If there are overhead power cables or other wires connected to the property, readings shall be obtained with the antenna directly under and in the same plane as the wires at the prescribed distance from the property.

Note: Theoretically, at 100% efficiency, the field from a fraction of a mW could exceed the 15 uV/m limit at the defined distance from the source.

The owner and operator of the system is responsible for ensuring that at the defined distance a possible interfering signal from the carrier current system does not exceed the maximum permissible field strength and does not cause interference to authorized radio services. In the event that interference is caused, the operator of the system shall promptly take steps to eliminate the interference and remedialmeasures would have to be taken to the extent of ceasing operation.

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B-9. Applications Based on Deletion of Assignments in the Plan (535-1605 kHz Band)

B-9.1 Deletion or Transfer of an Unused Assignment

B-9.1.1 As a number of the unused Canadian assignments in the Plan were based on an estimate of a need in a general area, such assignments may be transferred to an alternate community if the necessary protection criteria are met. The brief shall include a discussion of the assignments available in both communities.

B-9.1.2 If an application is based on the deletion of an unused assignment, other than a transfer, the applicant shall provide a detailed analysis demonstrating the unavailability of a satisfactory alternative; and

demonstrate that adequate alternate assignments are available in the Plan; or
propose modifications to the Plan to replace the deleted assignment.

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B-10. On-Air Testing Procedure

When the construction of the authorized facilities is complete, notice of on-air testing shall be given to the District Manager at least three weeks (unless otherwise specified in the letter of authority) prior to transmission tests. Departmental permission from the District Office is required for testing.

During on-air tests, identification of the station shall be made, preferably at 15-minute intervals, giving as a minimum the call sign, frequency and location of the station. In the case of rebroadcasting stations without capability to originate the aforementioned information, the broadcaster will be responsible for making the public aware that the new station is being tested. As an example, a notice could be placed in the local press which would explain that the broadcaster should be contacted in the event of interference difficulties that might develop. The broadcaster shall implement any instruction given by departmental representatives at the district, regional or headquarters level.

The required scope and duration of such on-air emission tests will depend to a large extent on the potential for interference that might be caused to existing broadcasting stations or other radio services. Such details of the testing shall be agreed upon with the local District Manager soon after the issuance of the letter of authority.

Following successful on-air tests, the applicant's consultant shall certify to the Department that the station is ready to commence operation in accordance with the approved technical submission and request permission to commence normal broadcasting schedule.