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BPR-4 — Application Procedures and Rules for Television Broadcasting Undertakings

Annex A — Propagation Curves

For the purposes of estimating field strength, when using the propagation curves in this annex, any HAAT values exceeding 1 600 metres will have to be entered as 1 600 metres.

Figure A1: Propagation Curves F(50,50) for Channels 2-6

Figure A1:  Propagation Curves F(50,50) for Channels 2-6 (the long description is located below the image)

Figure A2: Propagation Curves F(50,10) for Channels 2-6

Figure A2:  Propagation Curves F(50,10) for Channels 2-6 (the long description is located below the image)

Figure A3: Propagation Curves F(50,50) for Channels 7-13

Figure A3: Propagation Curves F(50,50) for Channels 7-13 (the long description is located below the image)

Figure A4: Propagation Curves F(50,10) for Channels 7-13

Figure A4: Propagation Curves F(50,10) for Channels 7-13 (the long description is located below the image)

Figure A5: Propagation Curves F(50,50) for Channels 14-69

Figure A5: Propagation Curves F(50,50) for Channels 14-69 (the long description is located below the image)

Figure A6: Propagation Curves F(50,10) for Channels 14-69

Figure A6: Propagation Curves F(50,10) for Channels 14-69 (the long description is located below the image)

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Annex B — Summary Sheet

Applicant:
space to insert Applicant name
Account Number:
space to insert Account Number
Address:
space to insert Address
space to insert Address
space to insert Address
Principal Service Location:
(including province)
space to insert Applicant name
Call Sign:
space to insert callsign
Originating Station:
(if rebroadcasting)
space to insert originating station
Call Sign:
space to insert callsign
Channel:
space to insert channel
Class:
space to insert Class
Offset:
space to insert Offset
Precision Offset:
space to insert Precision Offset
Site Details:
Street Address or Site Name:
space to insert Street Address or Site Name
City:
space to insert City
Province or Territory:
space to insert Province or Territory
Site Coordinates:
(WGS84)
space to insert Site Coordinates - degrees° space to insert Site Coordinates - minutes'space to insert Site Coordinates - seconds" N. Lat.
space to insert Site Coordinates - degrees°space to insert Site Coordinates - minutes' space to insert Site Coordinates - seconds" W. Long.
Transmitter:
Manufacturer / Model:
space to insert Manufacturer / Model
Output Power:
space to insert Output Power kW
Aural to Visual Ratio:
space to insert Aural to Visual Ratio %
Transmission Line:
Manufacturer / Type:
space to insert Manufacturer / Type
Length (m):
space to insert Length (m)
Line Loss (dB/100m):
space to insert Line Loss (dB/100m)
Line Efficiency:
space to insert Line Efficiency%
Other losses:
space to insert Other losses %
Antenna:
Manufacturer / Model:
space to insert Manufacturer / Model
Polarization:
space to insert Polarization
Directional / Non-directional:
space to insert Directional / Non-directional
Number of Bays:
space to insert Number of Bays
Largest Dimension:
space to insert Largest Dimension Metres
Beam Tilt:
space to insert Beam Tilt °
Power Gain:
space to insert Power Gain Maximum (Horizontal / Elliptical Polarization)
(w.r.t. Half-Wave Dipole)
space to insert Average (Horizontal / Elliptical Polarization) Average (Horizontal / Elliptical Polarization)

ERP:
space to insert ERPWatts Maximum
(at beam tilt, if applicable) (Horizontal / Elliptical Polarization)
space to insert ERPWatts Average:
(Horizontal / Elliptical Polarization)
EHAAT:
space to insert EHAAT Metres
OHAGL:
space to insert OHAGL Metres (Overall Height of Tower Structure Above Ground Level)
RCAGL:
space to insert RCAGL Metres(Radiating Centre Above Ground Level)
Ground Level:
space to insert Ground Level Metres (Above Mean Sea Level)

( ) Unattended ( ) Ancillary Service

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Annex C — Elevation Diagram of Typical Tower and Transmitting Antenna

Figure C1 — Elevation Diagram of Typical Tower and Transmitting Antenna

Figure C1 — Elevation Diagram of Typical Tower and Transmitting Antenna (the long description is located below the image)
Description of Figure C1

Figure C1 is an example of an elevation diagram of a typical tower and transmitting antenna. The tower is drawn as a vertical pole and the antenna is shown as a small vertical structure, attached to the tower. The ground level is drawn as a horizontal line running at the base of the tower. The average elevation of terrain is drawn as a horizontal line slightly below the ground level. The mean sea level is drawn as a horizontal line at the bottom of the graphic, below the average elevation of terrain. A horizontal line runs from the vertical center of the antenna and is identified as the Radiating Center.

There is a bidirectional arrow between the top of the tower and the line of the ground level, labeled as being of 300 meters high. Below, there is a bidirectional arrow between the line of the average elevation of terrain and the line of the mean sea level, labeled as being of 190 meters high.

Next, there is a bidirectional arrow between the line of the ground level and the line of the mean sea level, labeled as being of 211 meters high.

Next, the space between the top of the tower and the top of the antenna is surrounded by two pointing arrows and is labeled as being of 5 meters high. Below, there is a bidirectional arrow between the top and the bottom of the antenna, labeled as being of 35 meters high.

Next, there is a bidirectional arrow between the radiating center of the antenna and the line of the ground level, labeled as being of 277 meters high.

Next, there is a bidirectional arrow between the radiating center of the antenna and the line of the average elevation of terrain, labeled as being of 298 meters high.

Next, there is a bidirectional arrow between the radiating center of the antenna and the line of the mean sea level, labeled as being of 488 meters high.

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Figure D1: 47 dB Above 1 Microvolt per Metre Contour Channels 2-6

Figure D1: 47 dB Above 1 Microvolt per Metre Contour Channels 2-6 (the long description is located below the image)

Transmitting Antenna Height (metres)


Figure D2: 56 dB Above 1 Microvolt per Metre Contour Channels 7-13

Figure D2: 56 dB Above 1 Microvolt per Metre Contour Channels 7-13 (the long description is located below the image)

Figure D3: 64 dB Above 1 Microvolt per Metre Contour Channels 14-69

Figure D3: 64 dB Above 1 Microvolt per Metre Contour Channels 14-69 (the long description is located below the image)

Transmitting Antenna Height (metres)

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Annex E — Distance Versus Depression Angle (For Various Antenna Heights)

Figure E — Distance Versus Depression Angle (For Various Antenna Heights)

Annex E — Distance Versus Depression Angle (For Various Antenna Heights) (the long description is located below the image)

Depression Angle (in degrees)

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Annex F — Procedure to Determine Interference Zone

On an appropriately scaled map plot the transmitter sites 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 3.1.2.
  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 3.1.4.
  3. Mark the two points where the contours intersect.
  4. Repeat steps 1, 2 and 3 except 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 1 defines the interference zone.

Example

The following example shows the interference zone between an existing UHF Class B station and a proposed Class A station which are short-spaced and on co-channels.

  1. The protected service contour from Section 3.1.2 is 64 dBu which extends to 45 km.
  2. The interfering contour from Section 3.1.4 is 46 dBu (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 66 dBu service contour and the 48 dBu 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 tangent.
  5. Draw a line joining the intersection points obtained above. The area contained within this line and the protected service contour drawn in step 1 defines the interference zone. This area is shown cross-hatched in the drawing.

Figure F1: Interference Zone

Figure F1: Interference Zone (the long description is located below the image)
Description of Figure F1

The figure F1 shows how to calculate the interference zone as described in the example. At the left, a cross represents the protected station which is a class B station and it is surrounded by 4 arcs of circle corresponding to the following field strength contours: 70 dbu, 68 dBu, 66 dBu and 64 dBu. A dotted line between the station and the 64 dBu contour is labeled as being of 45 km long.

At the right, the interfering station which is a class A station, is surrounded by 4 arcs of circle corresponding to the following field strength contours: 52 dbu, 50 dBu, 48 dBu and 46 dBu.

The 68, 66 and 64 dBu contours from the protected station intersect respectively the 50, 48 and 46 dBu contours from the interfering station at two points each (one at the top and one at the bottom). The 70 dBu contour from the protected station is tangent to the 52 dBu contour from the interfering station and consequently, they intersect only in one point. The interference zone is shaded and drawn as follows. The right boundary of the interference zone follows the 64 dBu contour of the protected station between the two intersections with the 46 dBu contour from the interfering station. The left boundary follows the seven intersection points of the curves described above.

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Annex G — Television Ghost Investigation

Figure G1: Ghost Delay Versus Ghost Level for a Given Picture Grade

Figure G1: Ghost Delay Versus Ghost Level for a Given Picture Grade (the long description is located below the image)

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Annex H — Protection Criteria

Table H1: UHF Protection Criteria for Assignments With Operating Parameters
Greater Than 1000 kW ERP and/or 300 Metres EHAAT
Channel Separations Protection Criteria
± 1 The maximum permissible F(50,10) signal at the protected Grade B contour is equal to 100 dBu
± 2, ± 3 No overlap of 100 dBu contours calculated with F(50,50) curves
± 4 Protected site outside of proposed 74 dBu F(50,50) contours
 -7 No overlap of 74 dBu contours calculated with F(50,50) curves
 +14 The maximum permissible F(50,10) signal at the protected Grade B contour is equal to 110 dBu
 +15 The maximum permissible F(50,10) signal at the protected Grade B contour is equal to 92 dBu

Note: For international protection criteria, refer to the International Agreement.

For VHF allotments or assignments, where the separation is less than 96 km, the maximum permissible interfering signal at the adjacent channel's protected Grade B signal contour of a domestic assignment shall not exceed that shown in the table below using F(50,50) propagation curves.

Table H2a: Maximum Permissible Interfering Signal – Channels 2 to 6
Separation between TX Sites
(km)
Interfering Signal
(dBu)
D/U Protection Ratio (dB)
Between 95 and less than 96 96 -49
Between 93 and less than 95 84 -37
Between 92 and less than 93 77 -30
Less than 92 72 -25
Table H2b: Maximum Permissible Interfering Signal – Channels 7 to 13
Separation between TX Sites
(km)
Interfering Signal
(dBu)
D/U Protection Ratio (dB)
Between 95 and less than 96 93 -37
Between 93 and less than 95 89 -33
Between 90 and less than 93 87 -31
Between 87 and less than 90 84 -28
Between 84 and less than 87 82 -26
Less than 84 81 -25
Table H3a: Standard Separation Distances in Kilometres Required Between Canadian Classes of UHF Television Allotments and Assignments
Class of Allotment
/ Assignment
Channel Separation "r", Number of Channels Above (+) or Below (-) the Reference Channel "n"
Co-channel ± 1
Adjacent
D/U = -16 dB
at
D = 74 dBu
F(50,50)
or
D/U = -36 dB
at
D = 64 dBu
F(50,50)
± 2, ± 3
IM
No overlap
of
D = 100 dBu
F(50, 50)
U = 100 dBu
F(50,50)

+ 4
Adjacent

Locate
Outside

D = 74 dBu
F(50,50)

- 4
Adjacent

Locate
Outside

D = 74 dBu
F(50,50)

Channel
Accorded
Protection
n
Desired
(D)
Potential
Interfering
Channel
n + r
Undesired
(U)
Non-offset Offset
D/U = 35 dB
D = 64 dBu
F(50,50)
U = 29 dBu
F(50,10)
D/U = 18 dB
D = 64 dBu
F(50,50)
U = 46 dBu
F(50,10)
* Protection Provided at Potential Interfering Channel 64 or 74 dBu Contour.
C C 353 250 88 36 53 53
C B 328* 225* 77 25 53 30
C A 308* 205* 73 21 53 15
B C 328 225 77* 25 30 53
B B 248 153 52 14 30 30
B A 228* 133* 48 10 30 15
A C 308 205 73* 21 15 53
A B 228* 133 48 10 15 30
A A 163 85 28 6 15 15
Table H3b: Standard Separation Distances in Kilometres Required Between Canadian Classes of UHF Television Allotments and Assignments
Class of Allotment
/ Assignment
Channel Separation "r", Number of Channels
Above (+) or Below (-) the Reference Channel "n"

-7
Oscillator

No overlap
of

D = 74 dBu
F(50,50)
U = 74 dBu
F(50,50)

+ 14
Sound image

D/U = -46 dB
at
D = 64 dBu
F(50,50)
U = 110 dBu
F(50,50)

+ 15
Picture image

D/U = -28 dB
at
D = 64 dBu
F(50,50)
U = 92 dBu
F(50,50)

Channel
Accorded
Protection
n
Desired
(D)
Potential
Interfering
Channel
n + r
Undesired
(U)
* Protection Provided at Potential Interfering Channel 64 or 74 dBu Contour.
C C 106 80 99
C B 83 74 82
C A 68 72 75
B C 83 55 74
B B 60 49 57
B A 45 47 50
A C 68 35 54
A B 45 29 37
A A 30 27 30

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Annex I — Minimum Distance Separations

Table I1: Minimum Distance Separations in Kilometres Required Between Low-Power (LP) VHF and Other VHF Television Allotments and Assignments
Class of Station/System Channels 2-6 Channels 7-13
Channel Separation "r", Number of Channels Above (+) or Below (-) the Reference Channel "n"
Co-channel ± 1
Adjacent
Co-channel ± 1
Adjacent
Channel
accorded
protection (n)
Desired (D)
Channel
applied for
(n + r)
Undesired (U)
Non-offset Offset D/U = -16 dB
D = 47 dBu
F(50,50)
U = 63 dBu
F(50,10)
Non-offset Offset D/U = -16 dB
D = 56 dBu
F(50,50)
U = 72 dBu
F(50,10)
D/U = 35 dB
D = 47 dBu
F(50,50)
U = 12 dBu
F(50,10)
D/U = 25 dB
D = 47 dBu
F(50,50)
U = 22 dBu
F(50,10)
D/U = 35 dB
D = 56 dBu
F(50,50)
U = 21 dBu
F(50,10)
D/U = 25 dB
D = 56 dBu
F(50,50)
U = 31 dBu
F(50,10)
Regular LP 209 159 94 158 123 85
LP LP 132 82 17* 88 53 11*

Note 1:  Distances are based on VHF low-power operations having 100 watts ERP and 30 m EHAAT and regular stations operating with the maximum values given under Maximum Permissible Parameters in Section 3.1.1. For other low-power parameters, the desired-to-undesired (D/U) ratios in the table must be satisfied.

Note 2:  The Grade B contour is 12 kilometres and 8 kilometres respectively for channel 2-6 and 7-13.

Note 3:  In principle, those distances marked with as asterisk (*) may be eliminated if stations are co-sited.

Note 4:  Offset operations require a frequency stability of ± 1 000 Hz.

Table I2: Distance Separations in Kilometres Required to Assure Minimum Interference Within the Grade B Service Area of Low-Power VHF Television Broadcasting Stations From Other Classes of VHF Television Allotments or Assignments
Class of Station/System Channels 2-6 Channels 7-13
Channel Separation "r", Number of Channels Above (+) or Below (-) the Reference Channel "n"
Co-channel ± 1
Adjacent
Co-channel ± 1
Adjacent
Channel
accorded
protection (n)
Desired (D)
Channel
applied for
(n + r)
Undesired
(U)
Non-offset Offset D/U = -16 dB
D = 47 dBu
F(50,50)
U = 63 dBu
F(50,10)
Non-offset Offset D/U = -16 dB
D = 56 dBu
F(50,50)
U = 72 dBu
F(50,10)
D/U = 35 dB
D = 47 dBu
F(50,50)
U = 12 dBu
F(50,10)
D/U = 25 dB
D = 47 dBu
F(50,50)
U = 22 dBu
F(50,10)
D/U = 35 dB
D = 56 dBu
F(50,50)
U = 21 dBu
F(50,10)
D/U = 25 dB
D = 56 dBu
F(50,50)
U = 31 dBu
F(50,10)
LP Regular 367 290 90 323 258 78
LP LP 132 82 17* 88 53 11*

Note 1: Distances are based on VHF low-power operations having 100 watts ERP and 30 m EHAAT and regular stations operating with the maximum values given under Maximum Permissible Parameters in Section 3.1.1. For other low-power parameters, the desired-to-undesired (D/U) ratios in the table must be satisfied.

Note 2: The Grade B contour is 12 kilometres and 8 kilometres respectively for channel 2-6 and 7-13.

Note 3:  In principle, those distances marked with as asterisk (*) may be eliminated if stations are co-sited.

Note 4:  Offset operations require a frequency stability of ± 1 000 Hz.

Table I3: Minimum Distance Separations in Kilometres Required Between a Low-Power UHF Television Station and Other Classes of UHF Television Allotments or Assignments
Class of Station/System Channel Separation "r", Number of Channels Above (+) or Below (-) the Reference Channel "n"
Co-channel

± 1
Adjacent

D/U = -16 dB
D = 64 dBu
F(50,50)
U = 80 dBu
F(50,10)

± 2, ± 3, ± 4
Intermodulation

D/U = 0 dB
D = 100 dBu
F(50,50)
U = 100 dBu
F(50,50)

- 7
Oscillator
Radiation
D/U = 0 dB
D = 74 dBu
F(50,50)
U = 74 dBu
F(50,50)

+ 14
Sound Image

D/U =-28 dB
D = 64 dBu
F(50,50)
U = 92 dBu
F(50,10)

+ 15
Picture Image

D/U = -10 dB
D = 64 dBu
F(50,50)
U = 74 dBu
F(50,10)

Channel
accorded
protection
(n)
Desired
(D)
Channel
applied for
(n + r)
Undesired
(U)
Non-offset Offset
D/U = 28 dB
D = 64 dBu
F(50,50)
U = 36 dBu
F(50,10)
D/U = 18 dB
D = 64 dBu
F(50,50)
U = 46 dBu
F(50,10)
C LP 140 107 75 20 60 72 77
B LP 115 82 50 9 37 47 52
A LP 95 62 30 5 22 27 32
LP LP 82 49 17* 3* 14 14* 19

Note 1:  Distances are based on a UHF low-power operating at 5 kW ERP and 30 metres EHAAT (with a Grade B contour of 12 kilometres) and other UHF stations operating with parameters according to the class designations shown under Maximum Permissible Parameters in Section 3.1.1. For other low-power parameters the desired-to-undesired (D/U) ratios in the table must be satisfied at the desired contour.

Note 2:  In principle, those distances marked with an asterisk (*) may be eliminated if stations are co-sited.

Note 3:  Offset operations require a frequency stability of ± 1 000 Hz.

Table I4: Distance Separations in Kilometres Required to Assure Minimum Interference Within the Grade B (64 dBu) Service Area of Low-Power UHF Television Broadcasting Stations from Other Classes of UHF Television Allotments and Assignments
Class
of
Station/System
Channel Separation "r", Number of Channels Above (+) or Below (-) the Reference Channel "n"
Co-channel

± 1
Adjacent

D/U = -16 dB
D = 64 dBu
F(50,50)
U = 80 dBu
F(50,10)

± 2, ± 3, ± 4
Intermodulation

D/U = 0 dB
D = 100 dBu
F(50,50)
U = 100 dBu
F(50,50)

- 7
Oscillator
Radiation
D/U = 0 dB
D = 74 dBu
F(50,50)
U = 74 dBu
F(50,50)

+ 14
Sound Image

D/U =-28 dB
D = 64 dBu
F(50,50)
U = 92 dBu
F(50,10)

+ 15
Picture Image

D/U = -10 dB
D = 64 dBu
F(50,50)
U = 74 dBu
F(50,10)

Channel
accorded
protection
(n)
Desired
(D)
Channel
applied for
(n + r)
Undesired
(U)
Non-offset Offset
D/U = 28 dB
D = 64 dBu
F(50,50)
U = 36 dBu
F(50,10)
D/U = 18 dB
D = 64 dBu
F(50,50)
U = 46 dBu
F(50,10)
LP C 252 192 62 20 60 41 72
LP B 175 122 35 9 37 24 44
LP A 114 72 22 5 22 17 27
LP LP 82 49 17* 3* 14 14* 19

Note 1:  Distances are based on a UHF low-power operating at 5 kW ERP and 30 metres EHAAT (with a Grade B contour of 12 kilometres) and other UHF stations operating with parameters according to the class designations shown under Maximum Permissible Parameters in Section 3.1.1. For other low-power parameters the desired-to-undesired (D/U) ratios in the table must be satisfied at the desired contour.

Note 2:  In principle, those distances marked with an asterisk (*) may be eliminated if stations are co-sited.

Note 3:  Offset operations require a frequency stability of ± 1 000 Hz.

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Annex J — Zones One and Two Canada and U.S.A.

Figure J — Zones One and Two Canada and U.S.A.

Annex J — Zones One and Two Canada and U.S.A. (the long description is located below the image)
Description of Figure J

Figure J shows the map of Zone 1 in Canada and in United States.

The Zone 1 in Canada is the area between Windsor and Quebec which is located within the confines of the USA‑Canada border and the following lines: beginning from the West at the intersection of the common border and the latitude 44° 10′; thence in a straight line Northeast to the point of intersection of 77° longitude and 46° latitude; thence following the 46° latitude until the 75° longitude; thence in a straight line Northeast to the point of intersection of 72° longitude and 47° latitude; thence following the 47° latitude to the point of intersection with 71° longitude; thence following the 71° longitude Southwards to the common border. The Zone 2 in Canada is the area comprising the rest of Canada. It will be all Canadian territories except Zone 1.

The Zone 1 in the United States consists of that portion of United States located within the confines of the following lines drawn on the United States Albers Equal Area Projection Map (based on standard parallels 29° 30′ and 45° 30′; North American datum):  Beginning at the most easterly point on the State boundary line between North Carolina and Virginia; thence in a straight line to a point on the Virginia‑West Virginia boundary line located at north latitude 37° 49′ and west longitude 80° 12′ 30”; thence westerly along the southern boundary lines of the States of West Virginia, Ohio, Indiana and Illinois to a point at the junction of Illinois, Kentucky and Missouri State boundary lines; thence northerly along the western boundary line of the State of Illinois to a point at the junction of the Illinois, Iowa and Wisconsin State boundary lines; thence easterly along the northern State boundary line of Illinois to the 90th meridian; thence north along this meridian to the 43° 30′ parallel; thence east along this parallel to the United States‑Canada border; thence southerly and following that border until it again intersects the 43° 30′ parallel; then east along this parallel to the 71st meridian; thence in a straight line to the intersection of the 69th meridian and the 45th parallel; thence east along the 45th parallel to the Atlantic Ocean. When any of the above lines pass through a city, the city shall be considered to be located in Zone 1.

The Zone 2 in United States consists of that portion of the United States which is not located in Zone 1.

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Annex K — Television / Land-Mobile Mutual Interference Analysis (Provisional)

K1. Purpose

The purpose of this annex is to define the factors and to provide a method for evaluating mutual interference between land-mobile services and TV services on channel 7, 14 and 69 operating in adjacent frequency bands. It is to be noted that the present analysis does not deal with interference from multiple sources.

K1.1 Interference to Land Mobile

Interference to land-mobile base station receivers may occur when they operate near the site of a TV transmitter and on frequencies close to the TV channel (within 4 MHz). Such interference may be eliminated or reduced by increasing the physical separation of the stations.

The following are the types of interferences and possible remedies:

K1.1.1 Out-of-Channel Radiation From the Television Undertaking

This type of interference is produced intrinsically and with respect to the ambient "noise floor":

  1. Out-of-channel radiation by the television transmitter which can intrinsically create interference to LM. Normal operation usually results in video components* up to -60 dB in the adjacent channel, reference level being the peak envelope visual power.

    *Note: In the worst case, components as high as the below figures can exist for a few seconds at a time:
    -40 dB @ fv- 4.5 MHz (aural image, 3.25 ± 0.01 MHz below channel edge)
    -40 dB @ fv+ 9.0 MHz (visual image, 4.25 ± 0.01 MHz above channel edge)
    -60 dB @ fv- 3.58 MHz (chroma image, 2.33 ± 0.01 MHz below channel edge)
    -37 dB (worst case sporadic video components) down to 3 MHz below and up to 4 MHz above channel edge.

    Emissions at a specific frequency could, from a particular contributor, be reduced by a further 20 to 30 dB at the television transmitter by the use of special filters.

  2. LM usable sensitivity at VHF and UHF frequencies which is determined by internal noise and man-made noise. The sensitivity of a typical receiver is such that an input signal of 0.5 µV (-114 dBm, assuming a receiver input impedance of 50 Ω) would result in a 12 dB SINAD ratio at the output. To minimize the potential for interference to land-mobile receivers, out-of-channel television emissions at the specific LM carrier frequency and at the input of land mobile should ideally not exceed -120 dBm (assuming a signal to in terference ratio of 6 dB at that level).

While the above numbers apparently prohibit co-existence of LM and adjacent band television services except at great distances, statistical, technical and subjective factors have, in reality, proven that separation distances much lower than those implied by the theoretical numbers above can provide satisfactory results. In fact, a minimum separation distance** of 35 km is deemed to be sufficient for full power television undertakings. The minimum separation distance may be decreased by 3 km per dB of reduced ERP value to a minimum separation distance of 15 km.

**Note: The separation distance is based on out-of-channel (within 4 MHz from the edge of channel) TV emissions that are suppressed by 60 dB (referenced to peak envelope visual power), a receive LM antenna gain of 5 dB (10 dB for UHF) and a cross-polarization discrimination of 20 dB.

In real interference situations, the actual values that could be attributed to the above factors and in the note may differ from those assumptions. Additional factors such as TV antenna pattern, the degree of additional TV transmitter filtering and/or other rejections in the LM system may provide shorter separation distances.

The ambivalent nature of all these factors does not provide a sound foundation on which distance separation requirements could be based. The Department will therefore consider individual agreements between the TV applicant and the affected LM operators as an alternative to minimum separation distances.

K1.1.2 Desensitization of the Base Station Receiver

Interference can be minimized by installing cavity filters at the LM receiver to provide some rejection of the adjacent visual or aural carriers except where the frequency is too close.

K1.1.3 Intermodulation Products

Intermodulation products result from the mixing of two or more undesired signals at the input of the receiver. This may be eliminated by employing appropriate filters at the land-mobile receiver to reduce the magnitude of the TV signal contributing to the intermodulation product. If the intermodulation products are caused by mixing inside the receiver, upgrading the receiving equipment or better shielding may also alleviate the problem.

K1.2 Interference to Television

Figures K1 to K3 reflect measured values of protection ratio versus frequency separation for various channels.

In the case of channels 7 and 14, if a land-mobile transmitter of relatively high power is operating on a frequency near 2.33 MHz below the edge of the channels, a mixing process takes place producing severe color interference. For other frequencies in the lower 4 MHz adjacent band of channels 7 and 14 or in the entire upper adjacent 4 MHz band of channel 69, interference to television generally takes the form of distortion of the luminance information.

The potential for interference in the second, third and fourth adjacent TV channel is negligible.

LM assignments in the frequency band beyond 4 MHz from the edge of television channels can operate within the television service contour and provide the required protection. Within 4 MHz, however, full protection to television service from LM base station operations may be provided either through co-siting the TV transmitting antenna with the related adjacent channel LM base station transmitter, or by selecting the television site in such a way to keep the LM base station outside the proposed service contour (Grade B) where the protection ratios are met. These options may prove to be impractical in some cases due to location.

Co-siting TV and LM transmitters will result in a uniform signal differential inside the service contour of the television undertaking. The best approach to co-siting is to locate both the TV and LM transmitting antennas on the same tower or supporting structure. In such cases, similar antenna patterns are not needed as long as the TV/LM effective radiated power (ERP) ratio meets or exceeds that implied in Table K3. For best results, the LM receiver(s) should be kept at some distance rather than at the transmitting antenna site.

When not co-located, LM base station transmitters inside a television service contour will establish pockets of interference the size of which varies depending on the frequency separation and the strength of the television signal. As the separation distance between the two stations increases, the field strength of the TV signal decreases enlarging progressively the size of the area of interference. For all such cases, the applicant shall indicate the presence of interference zones from the related LM assignments on the coverage map. The interfering field strength of the land-mobile station may be calculated using the propagation curves of Figure K4.

Viewing tests were conducted in 1989 (refer to report BTRB-7 entitled Protection to Television from Land Mobile Stations Operating Adjacent to Television Channels 7, 13, 14 and 69) to determine the susceptibility of television receivers to adjacent band LM interference. LM signals in the frequency bands adjacent to channels 7, 14 and 69 were applied to the receiver terminals and the levels were adjusted for "Just Perceptible" interference. The viewing conditions for the assessment of picture quality were in accordance with the Recommendation ITU-R BT.500. The TV signal at the receiver terminal was adjusted to -25, -35 and -55 dBm (dB above 1 mW).

The average protection or rejection ratios obtained at the laboratory are based on non-varying desired and undesired input voltages at the receiver. In practice, it is necessary to define the percentage of time as well as the percentage of locations for which the desired quality of service is met.

The picture quality for coverage inside the Grade A (or Grade B) contour is defined as a picture of acceptable quality for at least 70% (50% for the Grade B) of receiver locations and 90% of the time. If F(50,50) propagation curves are used inside these contours, a time probability factor (T) and a location probability factor (L) have to be used to account for signal fading and terrain irregularities respectively. Consequently, protection to television reception from LM base station transmitters is derived from the following formula:

F u = F d PR + AD H ( L ) H ( T )
(1)

where:

Fu and Fd are the undesired LM and desired TV signal levels respectively. Fu is calculated by the free space propagation model out to 1 km. The "Egli propagation model" for 50% of locations is to be used for distances of in excess of 2 km (refer to Figure K4 of this annex). Interpolation is used to join the curves for distances of between 1 and 2 km. Fd is calculated by using the F(50,50) propagation curves. Figure K4 indicates the field strength for typical land-mobile stations with an ERP of 125 W (VHF) and 250 W (UHF). The appropriate field strengths for other ERP values can be obtained by shifting the curves ± 6 dB vertically for each multiplication/division of the ERP by a factor of 2. Field strengths are expressed in dBu.

PR is the average protection ratio in dB obtained from the receiver measurements (see figures K1 to K3 in this annex);

AD is the combined cross-polarization and directional discrimination of the TV receiving antenna against LM signals in dB (AD ≈15 dB when LM base station outside the Grade B, otherwise, AD = 0 dB);

H(L) is the adjustment made in dB with respect to the percentage of locations where the desired field strength level will be above the calculated value;

H(T) is the adjustment made in dB with respect to the percentage of time when the desired field strength level will be above the calculated value.

Table K1: H(L) and H(T) Values at VHF Frequencies (Channel 7)
Inside H(L) (in dB) H(T) (in dB) Total (in dB)
Grade A 4 3 7
Grade B 0 5 5
Table K2: H(L) and H(T) Values at UHF Frequencies (Channels 14 and 69)
Inside H(L) (in dB) H(T) (in dB) Total (in dB)
Grade A 6 3 9
Grade B 0 4 4
K.1.2.1 Near the Grade B Contour

The protection ratios of figures K1 to K3 are average values obtained at a TV receiver input level of -55 dBm. This level of signal represents viewing conditions close to the edge of the protected contour.

K.1.2.2 Co-located (Same Tower) TV and LM Transmitters

For TV receiving locations near the transmitting site, the television signal levels will be very high and therefore outdoor receiving antennas are not normally used. The reduced antenna size (rabbit ears) and its reduced height above ground limit the actual level. Measurements have indicated that the TV signal into the receiver using an indoor antenna inside the Grade A contour is usually between -25 and -35 dBm. In addition, it is assumed that the indoor TV receiving antenna provides no cross-polarization discrimination and indeed very little directional discrimination against vertically polarized LM transmissions, hence:

AD = 0 dB

Table K3 (below) gives the average values of the protection ratio for television. These are based on a receiver input level of -35 dBm (inside the Grade A contour). The ratios for -25 dBm are somewhat similar since they do not exhibit significant dependence on the level of the desired television signal.

Table K3: Average Desired (TV) to Undesired (LM) Protection Ratios
for TV Receiver Input Level of Between -25 and -35 dBm
TV Channels Frequency Separation (in MHz) of LM Base Station From the Edge of the TV Channel Protection Ratio (dB) at the Input of the Television Receiver
7 and 14 2 - 3 +12
> 3 0
69 > 2 +3

Figure K1: Desired (TV) to Undesired (LM) Protection Ratio Curves for Channel 7

Figure K1: Desired (TV) to Undesired (LM) Protection Ratio Curves for Channel 7 (the long description is located below the image)

Figure K2: Desired (TV) to Undesired (LM) Protection Ratio Curves for Channel 14

Figure K2: Desired (TV) to Undesired (LM) Protection Ratio Curves for Channel 14 (the long description is located below the image)

Figure K3: Desired (TV) to Undesired (LM) Protection Ratio Curves for Channel 69

Figure K3: Desired (TV) to Undesired (LM) Protection Ratio Curves for Channel 69 (the long description is located below the image)

Figure K4: Field Strength of Land Mobile Stations

Figure K4: Field Strength of Land Mobile Stations (the long description is located below the image)
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