BPR-3 — Application Procedures and Rules for FM Broadcasting Undertakings (sf09951)

Annex A — F(50,50) and F(50,10) Curves

For the purposes of estimating field strength, when using the propagation curves in this annex, any HAAT values exceeding 1600 m will have to be entered as 1600 m.

Figure A1 — Estimated Field Strength Exceeded at 50% of the Potential Receiver Locations for at Least 50% of the Time at a Receiving Antenna Height of 9.1 m

Figure A2 — Estimated Field Strength Exceeded at 50% of the Potential Receiver Locations for at Least 10% of the Time at a Receiving Antenna Height of 9.1 m

Annex B — Summary Sheet

Applicant:
Account Number:

Station:   New     Change  

Principal Service Location (including province):

Station Call Sign:

Originating Station (if rebroadcasting):

Channel Number:

Frequency:

MHz

Class of Station:

Site Details:
Street Address or Site Name:
City:
Province or Territory:

Antenna Coordinates (WGS84):
N. Lat. ° ' "
W. Long. ° ' "

Transmitter:
Manufacturer / Model / Certification Number:
Output Power: kW

Transmission Line:
Manufacturer/Type:
Length (m):
Line Loss (dB/100m):
Line Efficiency: %

Other Losses: %

Antenna:
Manufacturer / Model:
Polarisation:
Directional / Non-directional:
Number of Bays:
Largest Dimension: metres
Maximum Gain: dBd (Horizontal/Vertical/Circular Polarization)
Average Gain: dBd (Horizontal/Vertical/Circular Polarization)

ERP:
Maximum: kW (Horizontal/Vertical/Circular Polarization)
Average: kW (Horizontal/Vertical/Circular Polarization)
At Beam Tilt: kW Maximum
At Beam Tilt: kW Average

Heights:
EHAAT: metres
Radiating Centre (Above Ground Level): metres
Overall tower height (Above Ground Level): metres
Ground elevation (Above mean sea level): metres

Modes: Mono (  ), Stereo (  ), Unattended (  ), Automatic (  ), SCMO ( )

Annex C — Elevation Diagram of Typical Tower and Transmitting Antenna

Figure C1 — Elevation Diagram of Typical Tower and Transmitting Antenna

Annex D — Calculators

Figure D1 — Parameters Equivalent to an Effective Radiated Power of 50 W at a Transmitting Antenna Height of 60 m

Figure D2 — 0.5 Millivolt per Metre Contour Calculator

Figure D3 — 3 Millivolt per Metre Contour Calculator

Annex E — Systematic Method for Determining Low-Power FM (LPFM) Channel Availability

The following presents a systematic method for making a channel search.

1. List the numbers 201 to 300. Channels 201 to 220 should not be considered if there is reception of TV channel 6 in the proposed coverage area, or if there is a channel 6 allotment within 95 km of the LPFM transmitting site. If there is a limitation on the parameters of a channel 6 allotment, this distance may be somewhat reduced. Departmental advice can be sought in this regard.
2. On a suitable map, draw a circle centred at the proposed antenna site with a radius of 144 km(3 mV/m) if Table 8 is used, or 231 km if Table 9 is used.
3. Using the Canadian table of FM allotments starting at channel 201 and working up, check for centres located within the circle in (b). Measure on the map the distance to these centres and, using either Table 8 or Table 9, eliminate those channels whose allotments would preclude assignment to that centre. Take for example a centre that is 90 km away has an allotment listed as 250B. From Table 8 under class B, the required separation for co-channel operation is 97 km, but for first- adjacent channels, it is only 79 km. Thus, channel 250 is eliminated from the list in (a). If 0.5 mV/m coverage is wanted, from Table 9 , the required separation for first-adjacent channels is 109 km. Thus, channels 249, 250 and 251 cannot be used in this example.
4. If there are available channels after eliminating those affected by Canadian allotments, check whether the circle in (b) encloses any US territory. If there are still available channels, select one and enter it in the application form as part of the required technical data.
5. If no channels are available using Table 9, repeat from step (b) using Table 8.
6. If no channels are available based on Table 8, check whether any channel is eliminated by being less than 8 km short of any required separation, excluding those to other LPFM stations (see Section 5.4). A proposal based on such a channel might be considered acceptable under these circumstances.
7. If there are still no channels available, the services of a broadcast engineering consultant should be retained to perform a channel search.

Annex F — Procedure to Determine the Interference Zone

Plot the transmitter sites on an appropriately scaled map and do the following:

1. Plot the protected service contour for the assignment or allotment to be protected based on the maximum or other permissible parameters, as shown in Section 3.2.
2. Plot the interfering contour for the proposed assignment or allotment based on its proposed parameters in accordance with the interfering signal levels, as shown in Section 3.3.
3. Mark the two points where the contours intersect.
4. Repeat steps (a), (b) and (c), but increase the value of each contour while maintaining the same protection ratio until the protected and interfering contours are tangential.
5. Draw a line joining the intersection points obtained above. The area contained within this line and the protected service contour drawn in step (a) define the interference zone.

Example

The following example shows the interference zone between an existing class B station and a proposedclass A station which are short-spaced and on the same channel (co-channel):

1. The protected service contour from Section 3.2 is 54 dBµV/m, which extends to 65 km.
2. The interfering contour from Section 3.3 is 34 dBµV/m (the extent of this contour will vary depending on the proposed operating facilities).
3. Mark the two points where the contours intersect.
4. Plot the 56 dBµV/m service contour and the 36 dBµV/m interfering contour and mark the two points of intersection. Continue to increase the value of the contours, plot them, and mark the intersection points until the contours are tangential.
5. Draw a line joining the intersection points obtained above. The area contained within this curve and the protected service contour drawn in step (a) define the interference zone. This area is shown in grey in Figure F1.

Figure F1 — Interference Zone

Annex G — Procedure for Determining FM to TV Channel 6 Protection Requirements

G1. Purpose

To define the factors and to present a method for determining the protection requirements for TV channel 6 from FM broadcasting stations on channels 201 to 220 when co-located with TV channel 6 and when located outside the grade B contour of TV channel 6.

G2. TV Channel 6 Receiver Measurements

Laboratory measurements were taken on a number of TV receivers to determine the level at which the interference from FM signals on channels 201 to 220 was viewed as being just perceptible. The results are shown in Figure G1. The data showed an improvement of approximately 6 dB over earlier data. The curves of Figure G1 show the average FM to TV channel protection ratio for TV receivers for a picture quality of just perceptible interference. Since the protection varies with the level of the TV signal, separate curves are shown for different TV input levels.

G3. FM to TV Channel 6 Protection

The protection of TV channel 6 from FM stations is related to their field strength ratio by the following formula:

where:

F_u is the FM undesired signal and F_d is the desired TV signal levels both in dBµV/m; P_r is the protection ratio in decibels obtained from the receiver measurement;

G_r is the value in decibels to be added (or subtracted) to change the TV grade of picture from the just perceptible interference value to a specified picture quality;

A_d is the TV receiving antenna discrimination against the FM signals in decibels; and

L is the adjustment made in decibels with respect to the percentage of locations where the field strength level will be above the stated value.

G4. Co-located FM and TV Stations

For co-located FM and TV stations, the field strength of the TV signal will be very high in the vicinity of the TV antenna and therefore outdoor receiving antennas are not normally used. Measurement tests have indicated that the maximum TV signal into the receiver, using an indoor antenna, does not usually exceed 25 dBm. The reduced antenna size (rabbit ears) and its reduced height above ground limit the actual level.

The receiver level of −25 dBm has been used to derive the FM to TV protection ratios as shown in Table 6. It is recognized that a TV receiver input level of less than −25 dBm could be used, when justified, by the type of receiving antenna and possible shielding effect of the type of buildings where the receivers are located. The "antenna system gain" (antenna gain over any losses) can be as low as −29 dB (loss) for an antenna at a height of 2 m. This would place the receiver input signal at 38 dBm for an incident field of 115 dBµV/m, as determined from the F(50,50) field strength curves.

For co-located FM and TV transmitter sites, the TV receiving antenna provides no discrimination against the FM transmissions for horizontal polarization. In such cases, the antenna discrimination factor is zero. The FM power for vertical polarization can be increased 6 dB above the value determined for horizontal polarization.

The picture quality for coverage inside the grade A contour is defined as a picture of acceptable quality for at least 70% of the receiving locations, 90% of the time. Using the ITU-R five-point impairment scale, this acceptable quality has been equated to a picture impairment grade of 4.0.

As the laboratory measurements on the TV receivers were performed using an interference criterion of just perceptible or a picture impairment grade of 4.5, a correction of 3 dB is required to change to a picture impairment grade of 4.0. Given that the goal is to protect 70% of the receiver locations, which is the same percentage of receiver locations as used in the definition of the grade A contour, a 5 dB correction factor is used for "L" to equate the 50% used in the measurements (median value of the ratio) to 70% of protected receiver locations. Table 6 has been derived using the above factors in equation (1).

G5. FM Stations Outside the Grade B Contour

For FM stations located outside the grade B contour, the B contour (F_d = 47 dBµV/m) is protected and the FM to channel 6 field strength values shown in Table 7 have been calculated using the formula in equation (1) with the following considerations:

• the FM to TV channel 6 protection ratio (P_r) is based on measured values for a TV receiver input of −65 dBm; and
• for the antenna discrimination, a value of 6 dB is used. This value represents the performance of an average outdoor antenna as used at locations near the grade B contour.

The picture quality for coverage within the grade B contour is defined as a picture of acceptable quality for at least 50% of the receiving locations, 90% of the time. The acceptable quality has been equated to "interference is not annoying." As it is desirable to have an interference that does not degrade the picture, an ITU‑R picture impairment grade of 4.0 is used.

To change an ITU-R impairment grade of 4.5, (the condition under which the TV receivers were measured) to an impairment grade of 4.0, a value of 3 dB for G_r is used.

"L" in the equation represents the adjustment made in decibels with respect to the percentage of locations in excess of 50%. By using the F(50,10) propagation curves, and given that the interference value is exceeded for 50% of the locations, 10% of the time, the value of "L" is zero. Table 7 has been derived using the above factors in the formula of equation (1).

G6. Step-by-Step Procedure

Use the following steps to determine the maximum power of the FM station that is co-located with a channel 6 TV station:

1. Using Table 6, which shows the permissible power ratio for FM channels 201 to 220 inclusive, select the FM to TV power ratio for the proposed FM channel.
2. Using the ERP of the TV station, determine the power of the FM station by adding the power ratio in step 1 to the ERP of the TV station as converted to decibels. If the TV antenna pattern is directional, the permissible FM power shall be calculated for the different azimuths.
3. If the FM antenna height differs by 30 m or more from the height of the TV antenna, the ERP of the FM antenna shall be adjusted to correspond to its equivalent value.

The equivalent value is calculated by the following procedure:

1. Using the FM ERP as determined in step 2 above and the EHAAT for the TV station, determine the distance to the FM 100 dBµV/m contour using the F(50,50) field strength curves.
2. Using the same curves, determine the FM ERP that will place the 100 dBµV/m contour at this same distance using the EHAAT of the FM station.

To determine the maximum power (ERP) of the FM station when the station is located outside the grade B contour of the channel 6 TV station, use the following steps:

1. Using Table 7, which shows the permissible FM field strength level, select the field strength level of the proposed FM channel.
2. From the field strength level in step 1 above, determine the maximum ERP using the F(50,10) propagation curves and the EHAAT of the station. The ERP represents the maximum radiation in the direction of the channel 6 grade B contour.

Figure G1 — FM/Channel 6 Protection Ratios (Just Perceptible Interference)

Annex H — FM/NAV/COM Protection Criteria

H1. Interference Mechanisms and Compatibility Criteria

H1.1 Type A₁ Interference

For the analysis of type A₁ interference, the following two categories of spurious emissions exist:

• spurious emissions resulting from an intermodulation process caused at the transmitter site, e.g. by multiple transmitters feeding the same antenna; and
• other spurious emissions.

Where the actual frequency of the spurious emission is known, Table H1 gives the values of protection ratio used for frequency differences up to 200 kHz from aeronautical frequencies (radionavigation and radiocommunication). Type A₁ interference does not need to be considered for frequency differences greater than 200 kHz.

H1.2 Type A₂ Interference

The protection ratio values used are given in Table H2.

A frequency difference of less than 150 kHz cannot occur. For frequency differences greater than300 kHz, this type of interference does not need to be considered.

Note: FM sound broadcasting stations may, in some regions, employ compression techniques and/or provide services on subcarrier frequencies up to 99 kHz. Combinations of these practices, especially when associated with a carrier deviation larger than ± 75 kHz, may result in a 0 to 10 dB increase in susceptibility to type A₂ interference of an instrument landing system (ILS) receiver. Also, type A₂ interference does not need to be considered for COM receivers.

H1.3 Type B₁ Interference

Third-order intermodulation products of the form:

1. f_intermod=2f₁−f₂ (two-signal case); or
2. f_intermod=f₁+f₂−f₃ (three-signal case)

with f₁>f₂>f₃,

generated in the airborne ILS or very-high-frequency omnidirectional range (VOR) receiver will cause an unacceptable degradation of receiver performance, if f_intermod coincides with the frequency of the wanted signal and if the inequalities given below are fulfilled.

Intermodulation of the second order is irrelevant and intermodulation of a higher order than three has not been considered.

(1) Two-signal case:

\[2(N_1 - 20log \frac{max(0.4;108.1-f_1)}{0.4}) +\]

\[N_2 - 20log \frac{max(0.4;108.1-f_2)}{0.4} + 120 \ge 0\]

(2) Three-signal case:

\[N_1 - 20log \frac{max(0.4;108.1-f_1)}{0.4} +\]

\[N_2 - 20log \frac{max(0.4;108.1-f_2)}{0.4} +\]

\[N_3 - 20log \frac{max(0.4;108.1-f_3)}{0.4} + 126 \ge 0\]

N₁, N₂ and N₃ have the following meaning:

N₁: level (dBm) of the broadcasting signal of frequency f₁ (MHz) at the input of the NAV receiver;

N₂: level (dBm) of the broadcasting signal of frequency f₂ (MHz) at the input of the NAV receiver; and

N₃:  level (dBm) of the broadcasting signal of frequency f₃ (MHz) at the input of the NAV receiver.

max (0.4; 108.1 −f) means either 0.4 or 108.1 −f, whichever is greater.

H1.3.1 Frequency Offset Conditions

When the intermodulation product falls close to the frequency of the wanted signal, a correction is applied to each signal level which is a function of the frequency difference between the NAV signal and the intermodulation product. This correction is shown in Table H3.

N_1,2,3 (corrected) = N_1,2,3−correction term

For frequency differences beyond ±200 kHz, type B₁ interference does not need to be considered. For COM receivers, the Venn diagram method shall be used.

H1.4 Type B₂ Interference

Table H4 contains maximum permitted levels of broadcasting signals at the input to the airborne ILS or VOR receiver.

For intermediate values, the maximum permitted level is determined by linear interpolation. For COM receivers, the level of any FM signal should not exceed −10 dBm.

H2. Selection of Aeronautical Test Points

For a test point height of:

• 2450 m above sea level (ASL) for ILS; and
• 12200 m ASL for VOR;

Table H5 lists separation distances between a broadcasting station with a given ERP and frequency, and the test point of an aeronautical radionavigation station beyond which it is considered unlikely that the service of the aeronautical station would be affected. The more critical requirements are those for types A₁ and B₁ interference; the higher of the two separation distances is shown in Table H5.

In general, broadcasting stations which are:

• more than 500 km from a VOR/COM test point;
• more than 255 km from an ILS test point; or
• beyond the radio line-of-sight from a VOR or ILS test point;

are considered as being unlikely to affect the service of that aeronautical radionavigation station.

H3. Compatibility Assessments

For the purpose of compatibility assessment, an interference prediction model, based on the compatibility criteria given in Section H1 of this annex, is used.