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1995 No. 74 RADIOCOMMUNICATIONS (MULTIPOINT DISTRIBUTION STATION LICENCES - REGIONAL LICENCES) GUIDELINES No. 1 of 1995 - SCHEDULE 1

                           SCHEDULE 1               Subclause 3(1)

ASSESSMENT ASSESSMENT A - MDS TRANSMITTER TO MDS RECEIVER PURPOSE OF
ASSESSMENT OF INTERFERENCE FROM MDS TRANSMITTER TO MDS RECEIVER The
assessments A.1, A.2 and A.3 below specify how to assess the potential for
interference from an MDS transmitter to co-channel or adjacent channel MDS
receivers for the purposes of Guidelines 14(a), (b) and (c).
A.1   MDS TRANSMITTER TO CO-CHANNEL MDS RECEIVERS IN OTHER LICENCE
AREAS A.1.1. This assessment (A.1) is intended to lead, where necessary, to
the imposition of a licence condition aimed at ensuring that the field
strength from an MDS transmitter does not exceed 32 dBuV/m in any other
co-channel licensee's MDS licence area.
Step 1: Identifying if an Interference Assessment is Necessary A.1.2. The
following information is needed to decide if an interference assessment must
be carried out:
Information provided by MDS Licensee
- MDS transmitter location
- MDS transmitter channel
Information provided by the SMA
- MDS licence area boundaries
(NOTE. Details of the MDS licence area boundaries are contained in Schedule 1
to the Radiocommunications (Allocation of Multipoint Distribution Station
Licences - Regional Licences) Determination No. 1 of 1995.) A.1.3. An
assessment of the potential for interference from an MDS transmitter to
another MDS licence area is necessary if the MDS transmitter is to be located
within a distance 'D' of another MDS licence area. The distance 'D' is
determined from the height of the transmitting antenna of the MDS transmitter
above average ground level and is indicated in the following table.
      Height of Transmitting Antenna above         D

          Average Ground Level, Ht*               (km)


   (m) 
                  Ht<-37.5                        65

                37.5- PR where:
Pw = wanted power, calculated at step 3 (dBm)
Pu = unwanted power, calculated at step 3 (dBm)
PR = is the protection ratio required by a fixed link receiver from an MDS
transmitter at frequency offset of fo MHz (dB) (see Schedule 5)
fo = frequency difference between MDS transmitter frequency and fixed link
receiver frequency (MHz) fo is calculated from the equation:
fo = the absolute value of (fMDS - fr)
where:
fMDS = MDS transmitter channel centre frequency (MHz)
fr = fixed link receiver centre frequency (MHz)
(NOTE. The results of Assessment D may lead to the imposition of licence
conditions, see Guideline 14(e)).)
(NOTE. Secondary fixed link receivers cannot claim protection from
interference from an MDS transmitter. The SMA will advise the licensee of the
secondary fixed link of the potential for interference. Secondary fixed link
licences should already be subject to the condition that the service cannot
claim protection from, or cause interference to, services of a primary status.
If not, a licence condition may be imposed on the licence authorising
operation of the secondary fixed link (see Guideline 15).) ASSESSMENT C -
FIXED LINK TRANSMITTER TO MDS RECEIVER PURPOSE OF ASSESSMENT OF INTERFERENCE
FROM FIXED LINK TRANSMITTER TO MDS RECEIVER This Assessment C specifies how to
assess the potential for interference from a primary or secondary fixed link
transmitter to a notional MDS receiver lying within a defined area (called an
assessment area). This assessment is intended to lead, where necessary, to the
imposition of a licence condition on a secondary fixed link transmitter, where
the unwanted field strength from that secondary fixed link transmitter
received by a notional MDS receiver in an assessment area is calculated to
exceed protection requirements (see C.9. below).
(NOTE. The references in steps 1 - 4 below to 'fixed link' transmitters are to
both primary and secondary fixed link transmitters.) Step 1: Identifying if an
Interference Assessment is Necessary C.1. The following information is needed
to decide if an interference assessment must be carried out:
Information provided by MDS Licensee
- MDS transmitter location
- MDS transmitter frequency
(NOTE. The location and channel of the MDS transmitter are required because
the notional MDS receiver for which this assessment (C) may be required is
deemed to be lying within the assessment area around that MDS transmitter. The
assessment area is bounded by a circle of radius R kilometres from the MDS
transmitter. The radius R is related to the transmitter height and EIRP, and
is calculated in accordance with Schedule 3. See also C.4. below.)
Information provided by the SMA
- location and frequency of fixed links
(NOTE. The details of the location and frequency of fixed link receivers are
held by the Spectrum Management Agency.) C.2. An assessment of the potential
for interference to an MDS receiver from a fixed link transmitter is necessary
if the MDS transmitter is located within a distance D from a fixed link
transmitter as indicated in the following table, and the fixed link
transmitter is operating in the frequency range:
2040 - 2147 MHz for Group A MDS channels; or
2266 - 2420 MHz for Group B MDS channels.
      Ht*           EIRP**   (Watts)


   (metres)
             100     200    1000    2000    10000

    37.5     216     222     227     229     234

     75      216     223     237     239     244

    150      216     223     250     252     257

    300      216     223     250     271     277

    600      216     223     250     271     304

    1200     216     223     250     271     344

Values for D (km)

* Ht: MDS transmitting antenna height above the average level of the ground
between distances of 3 and 15 km from the transmitter in the direction of the
receiver (see CCIR Rec 370-5)

**EIRP: the EIRP of the proposed MDS transmitter
(NOTE. CCIR Recommendations are available from the Standards Australia
International Sales Group, Strathfield NSW.) Step 2: Calculating Terrain Loss
C.3. The following information is needed to complete this calculation:
Information provided by MDS Licensee
- location and site height of the point in the assessment area
around the proposed MDS transmitter nearest to the fixed link
transmitter
(NOTE. For the purpose of this assessment, the point described above
represents the location of the antenna of a notional MDS receiver, with
nominal antenna height as specified below.)
- fixed link transmitter site height (determined by knowing the
fixed link transmitter location)
- terrain profile between the fixed link transmitter and the
point in the assessment area around the MDS transmitter nearest
to the fixed link transmitter
Information provided by the SMA
- fixed link transmitter location and antenna height
- nominal MDS receiver antenna height = 10m
(NOTE. The details of the locations and of some antenna heights of fixed link
transmitters are held by the Spectrum Management Agency. If the antenna height
of the link under consideration is not held by the Spectrum Management Agency
a height of 70 m may be used, or specific height information sought from the
fixed link licensee.) C.4. The assessment area is bounded by a circle of
radius R kilometres from an MDS transmitter. The radius R is proportional to
the transmitter height and EIRP, and is calculated in accordance with Schedule
3. C.5. Using the method detailed at Schedule 2, calculate the terrain loss
between the fixed link transmitter and the point in the assessment area around
the MDS transmitter that is nearest to the fixed link transmitter.
(NOTE. If the protection criteria of Assessment C.9. are satisfied when a
terrain loss value of Lt = 0 dB is used in the equation at assessment C.7.
then calculation of an actual value for Lt is not required.) Step 3:
Calculating Received Signal Levels C.6. The following information is needed
for this calculation: Information provided by MDS Licensee - terrain loss
(calculated in the same manner as under Step 2, para C.5)
Information provided by the SMA
- fixed link transmitter power and antenna gain in the direction
of the point in the assessment area around the MDS transmitter
that is nearest to the fixed link transmitter C.7. The unwanted field strength
(at an MDS receiver) is then calculated at the point in the assessment area
around the MDS transmitter that is nearest to the fixed link transmitter using
the following equation:
Eu = 44.77 - 20log(d) + Pt + Gtm - Lt where:
Eu = unwanted field strength (dBuV/m)
d = distance between fixed link transmitter and the point in the assessment
area around the MDS transmitter that is nearest to the fixed link transmitter
(km)
Pt = fixed link transmitter power (dBm)
Gtm = gain of the fixed link transmitter antenna in the direction of the point
in the assessment area around the MDS transmitter that is nearest to the fixed
link transmitter (dBi)
Lt = terrain loss (as calculated at Step 2)(dB)
(NOTE. The Spectrum Management Agency holds details of both the power, and the
antenna gain, of fixed link transmitters. If either the transmitter power or
the antenna gain of the link under consideration is not held by the Spectrum
Management Agency, the value in the EIRP data field may be used in lieu of the
combined value of Pt + Gt. If the EIRP is also not held by the Spectrum
Management Agency, then the values of Pt and Gt must be sought from the fixed
link licensee. The boresight gain value (or EIRP, as applicable) should then
be de-rated in accordance with the 2.1 GHz Fixed Link Notional Antenna
Radiation Pattern at Schedule 4, to find the off-axis gain (Gtm) (or EIRP) in
the relevant direction. Note that off-axis antenna gain (or EIRP) should be
considered in both the horizontal and vertical planes.) Step 4: Assessing
Received Signal Levels Against Protection Requirements C.8. The following
information is needed for this assessment:
Information provided by MDS Licensee
- unwanted field strength (as calculated at Step 3)
- MDS transmitter channel centre frequency
Information provided by the SMA
- MDS receiver protection requirements (see Schedule 6)
- fixed link transmitter centre frequency (ft) C.9. A fixed link transmitter
will meet the protection requirements for MDS receivers if:
Eu <- Em
 where:
Eu = unwanted field strength calculated at Step 3 (dBuV/m)
Em = the maximum permissible unwanted field strength in the assessment area
around the MDS transmitter at frequency offset of fo MHz (dBuV/m) (see
Schedule 6)
fo = frequency difference between MDS transmitter channel centre frequency and
fixed link transmitter frequency (MHz) fo is calculated from the equation:
fo = the absolute value of (fMDS - ft) where:
fMDS = MDS transmitter channel centre frequency (MHz)
ft = fixed link transmitter centre frequency (MHz)
(NOTE. Details of the centre frequencies of fixed link transmitters are held
by the SMA.)
(NOTE. The results of Assessment C may lead to the imposition of licence
conditions, see Guideline 16.) ASSESSMENT D - MDS TRANSMITTER TO EARTH STATION
RECEIVER This Assessment D specifies how to assess the potential for
interference from an MDS Group B transmitter to an earth station receiver in
the space research service. A detailed discussion of the interference
mechanisms between MDS and earth stations can be found in Section 2 Part B of
the Coordination Handbook. The SMA considers that earth station receivers in
the space research service are not likely to receive interference from Group A
MDS transmitters. Accordingly, no assessment of the interference potential to
earth station receivers from Group A MDS transmitters need be carried out.
Step 1: Identifying if an Interference Assessment is Necessary D.1. The
following information is needed to decide if an interference assessment must
be carried out:
Information provided by MDS Licensee
- MDS transmitter location
- MDS transmitter EIRP (in dBm)
Information provided by the SMA
- Location of Parkes earth station
- Location of Tidbinbilla earth station
(NOTE. For information on the locations of the Parkes and Tidbinbilla earth
stations see Schedule 7.) Parkes D.2. An assessment of the potential for
interference to the Parkes earth station is necessary if an MDS transmitter is
to be located within a circle around the Parkes facility of radius:
    250 km                    for an MDS transmitter EIRP <- 60 dBm

    250 + 12(EIRP - 60) km    for an MDS transmitter EIRP > 60 dBm
Tidbinbilla D.3. An assessment of the potential for interference to the
Tidbinbilla earth station is necessary if an MDS transmitter is to be located
within a circle around the Tidbinbilla facility of radius:
    180 km                    for an MDS transmitter EIRP <- 60 dBm

    180 + 12(EIRP - 60) km    for an MDS transmitter EIRP > 60 dBm
D.4 If an interference assessment is necessary, the assessment will comprise
the following steps 2 - 4. Step 2: Calculating Propagation Loss D.5. The
following information is needed to complete this calculation: Information
provided by MDS Licensee - MDS transmitter location, site height, antenna
height and antenna gain in the direction of the earth station receiver -
terrain profile between MDS transmitter and earth station receiver
Information provided by the SMA
- Earth station receiver location, site height, antenna height
and antenna gain in the direction of the MDS transmitter (see
Schedule 7)
- required time percentage for which the calculated basic
transmission loss is not exceeded (see Schedule 8)
- meteorological data for path profile under assessment
(see Schedule 8) D.6. The propagation loss between the MDS transmitter and the
earth station receiver under assessment is to be calculated using ITU Rec
452-5 (see Schedule 8).
(NOTE. ITU Recommendations are available from the Standards Australia
International Sales Group, Strathfield NSW.) Step 3: Calculating Received
Signal Levels D.7. Calculating Received Power (at the earth station receiver)
D.7.1. The following information is needed for this calculation:
Information provided by MDS Licensee
- MDS transmitter power
- MDS antenna gain in the direction of the earth station receiver
- propagation loss (as calculated at Step 2)
Information provided by the SMA
- earth station receiver antenna gain
- allowance factor for multiple MDS transmitters D.7.2. The received power (at
the earth station receiver) is then calculated using the following equation:
Pr = Pt + Gte - Lb + Grm + Fa where:
Pr = power received (dBm)
Pt = proposed MDS transmitter power (dBm)
Gte = proposed MDS antenna gain in the direction of the earth station receiver
(dBi)
Lb = propagation loss (as calculated at Step 2) (dB)
Grm = gain of the earth station antenna in the direction of the MDS
transmitter (dBi) (see Schedule 7)
Fa = factor to account for the additive contributions from multiple MDS
transmissions (dB) (see Schedule 7) D.8. Calculating Received Noise Power (at
the earth station receiver) D.8.1. The following information is needed for
this calculation:
Information provided by MDS licensee
- MDS transmitter power
- MDS antenna gain in the direction of the earth station receiver
- propagation loss (as calculated at Step 2)
Information provided by the SMA
- earth station receiver antenna gain
- MDS emission limits in the band 2290 - 2300 MHz
- allowance factor for multiple MDS transmitters D.8.2. The received noise
power (at the earth station receiver) is then calculated using the following
equation:
Prn = Ptn - Lb + Grm + Fa where:
Prn = received noise power (dBm in a 1 Hz bandwidth)
Ptn = deemed transmitted MDS noise power in the band 2290 - 2300 MHz* (dBm in
a 1 Hz bandwidth)
Lb = propagation loss (as calculated at Step 2) (dB)
Grm = gain of the earth station antenna in the direction of the MDS
transmitter (dBi) (see Schedule 7)
Fa = factor to account for the additive contributions from multiple MDS
transmissions (dB) (see Schedule 7)

* For the purposes of this calculation, the transmitted MDS noise power (Ptn)
is deemed to be:
    for channel 6 transmitters        (EIRP - 56.25) dBm in a 1 Hz

bandwidth
    for channel 7 - 19 transmitters   (EIRP - 90) dBm in a 1 Hz

bandwidth where:
EIRP is the equivalent isotropically radiated power (in dBm) of the proposed
MDS transmitter in the direction of the earth station receiver
(NOTE. If a licensee can demonstrate to the SMA that the noise power of the
proposed MDS transmitter is less than the relevant limit specified above, then
the actual noise power of the proposed transmitter may be used instead of the
deemed noise power.)
(NOTE. The rationale for this approach is given in the Coordination Handbook.)
Step 4: Assessing Receive Levels Against Protection Requirements D.9. An MDS
transmitter will meet the earth station receiver protection requirements if
the levels calculated at Step 3 do not exceed those listed below: Parkes
  receiver overload       Prmax  = -30 dBm in the band 2240 - 2340 MHz

noise floor degradation Prnmax = -192 dBm in a 1 Hz bandwidth
in the band 2290 - 2300 MHz Tidbinbilla
  receiver overload       Prmax  = -84 + 3.5(n-6) dBm

(n is the MDS channel number in
the range 6 to 19)
noise floor degradation Prnmax = -192 dBm in a 1 Hz bandwidth in the
band 2290 - 2300 MHz
(NOTE. The results of Assessment D may lead to the imposition of licence
conditions, see Guideline 14.) 


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