IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY, VOL. EMC-19, NO. 3, AUGUST 1977
`
`171
`
`The 1977 WARC on Broadcasting Satellites: Spectrum
`Management Aspects and Implications
`RICHARD G. GOULD, SENIOR MEMBER, IEEE, AND EDWARD E. REINHART, MEMBER, IEEE
`
`Abstract- Broadcasting satellites are allocated as a primary service in
`the band 11.7-12.2 GHz (11.7-12.5 GHz in Europe, Africa, and the
`USSR), but the band is also allocated on a primary basis (equal sharing)
`to other services-fixed, mobile, broadcasting, and fixed satellite.
`Presented with these difficult sharing situations, delegates from over
`100 countries met at an ITU World Administrative Radio Conference in
`1977 to develop a plan for broadcasting satellites.
`Many nations wanted a plan that would assign to them now, re-
`served orbital locations and channel assignments for their future use.
`Other countries wanted a plan adopted now for future broadcasting
`satellites which assigned specific channels to specific areas on the
`ground so that they could use the remaining frequencies to provide
`terrestrial service right away.
`This paper describes the "Plan" developed at the conference and
`points out how the principles of spectrum management were employed.
`It also discusses the implications for future international management
`of the spectrum growing out of this meeting.
`
`INTRODUCTION
`
`THE 1977 World Administrative Radio Conference on
`Broadcasting Satellites (WARC-BS) was one of a series of
`international regulatory conferences held under the auspices
`of the International Telecommunication Union (ITU). Such
`conferences can be either world or regional (there are three
`ITU Regions as shown in Fig. 1, the Western Hemisphere con-
`stituting Region 2) and either general (treating all services and
`frequency bands) or specialized (dealing with one or a speci-
`fied number of services and frequency bands). The WARC-BS
`was a specialized world conference dealing with the broadcast-
`ing satellite service (BSS) and the services with which it shares
`the 12-GHz band. Although it was a world conference it
`arrived at different conclusions for different Regions.
`This conference is the most recent instance of intemational
`management of the radio frequency spectrum. The conference
`employed the traditional techniques of spectrum manage-
`ment-constraining signal and equipment parameters and the
`location of stations in the different radio-communications
`services involved-to permit frequency sharing within and
`between services while avoiding unacceptable interference to
`any one of them. However, the agreements of this conference
`regarding the BSS were detailed and specific and included a
`comprehensive plan assigning
`administrations
`in ITU
`to
`Regions 1 and 3, individual channels (that is, frequencies) and
`
`Manuscript received June 24, 1977. This work was supported by the
`National Aeronautics and Space Administration, however, the views ex-
`pressed are those of the authors.
`R. G. Gould is with Telecommunications Systems, Washington, DC
`20006. (202) 223-4449.
`E. E. Reinhart was with Jet Propulsion Laboratory, Pasadena, CA
`91103. He is now with Communications Satellite Corporation, Wash-
`ington, DC.
`
`orbital locations for coverage of
`polarizations at specific
`prescribed service areas on the ground. This is in marked
`contrast to the traditional practice in the fixed-satellite service
`(FSS) where the choice of orbital location and of the fre-
`quencies used within the allocated bands is on a "first-come,
`first-served" basis.
`The agreements reached at the 1977 conference [I ] could
`presage the adoption of similarly structured plans for other
`services and for other bands. This would mean a significantly
`more ordered and regulated use of the orbit and spectrum than
`heretofore.
`As another example of this possible trend toward a more
`structured use of the orbit and spectrum, consider the concept
`of the "Scaling Law." This concept, which arose outside the
`context of the 1977 WARC-BS, and is intended to apply to
`the fixed-satellite service (FSS), has been discussed within
`INTELSAT and in Interim Working Party 4/1 of the CCIR
`which has as its objective the study of the efficient utilization
`of the orbit and the spectrum. Under this concept, the per-
`missible level of interference from one satellite network to
`another would be made a function of the spacing between the
`two satellites, rather than the single value now set forth in
`CCIR Recommendation 466 [2]. Under the present recom-
`mendation, each interfering satellite is permitted to introduce
`up to 400 pWOp to an interfered-with satellite, regardless of
`how far removed it is from that satellite. Applying the scaling
`law would restrict a satellite far removed from another to
`introduce significantly less interference.
`In the case of the 1977 conference, there were two driving
`forces behind the determination of most of the countries who
`participated (with the notable exceptions of the United
`States, Canada, and Brazil) to agree upon a detailed rigid plan
`of frequency and orbital postion assignments:
`* the concern of the developing countries that not enough
`frequencies and orbital positions would still be available by
`the time they were ready to launch and use broadcasting
`satellites;
`* a desire, primarily by European countries, to use frequen-
`cies in the 12-GHz band for terrestrial systems in the near
`future which, under Footnotes 405BA and 405B to the
`ITU Radio Regulations [3], could not be used until a world
`or regional administrative conference had made plans for
`the MSS.
`Both forces spring from an awareness that the geostationary
`orbit and spectrum are limited natural resources.
`In choosing a rigid "a priori" plan guaranteeing access to
`the orbit and spectrum in the future, the international tele-
`communications community rejected the principal alternative:
`a less-structured evolutionary approach in which administra-
`
`Exhibit 2005
`IPR2015-01077
`
`

`
`172
`
`IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY, VOL. EMC-19, NO. 3, AUGUST 1977
`
`ti2C
`
`X00.
`
`80.
`
`601
`
`401
`
`20.
`
`0.
`
`20.
`
`The shaded part represents the Tropical Zone
`
`Fig. 1.
`
`Chart of Regions as defined in Table of Frequency Allocations.
`
`tions would establish individual systems following a set of
`technical guidelines intended to encourage efficient utilization
`of the orbit and spectrum. This latter method would retain
`some of the traditional freedom of action that sovereign
`nations have always reserved to themselves.
`The nature and extent of the frequency sharing problem
`faced by the 1977 conference was determined by the 1971
`World Administrative Radio Conference for Space Tele-
`communications (WARC-ST) when it made allocations to
`services in the 12-GHz band (Table I). Sharing a
`several
`frequency band among different Regions of the world may be
`comparatively easy if the systems in these services have
`similar technical characteristics or if their radiations are con-
`fined by physical laws to a single Region. However, alloca-
`tion in the same Region, as well as in adjacent Regions, of the
`same frequencies to services with vastly different characteris-
`tics and with the wide geographical coverage typical of satel-
`lite systems, can pose extremely difficult sharing problems.
`Consider the specific situation facing the 1977 conference:
`broadcasting satellites are, almost by definition, high power,
`and the earth stations they serve have small diameter and,
`consequently, wide beamwidth, antennas. Such systems are
`not intrinsically good neighbors to other space systems work-
`ing at lower signal levels with narrower beam earth station
`anltennas, as in the FSS; nor to terrestrial systems with simple
`receivers as in the broadcasting service; or to terrestrial systems
`with a low tolerance to interference as with the high-capacity
`high-quality for telephone and data circuits, used in the fixed
`service. The agenda of the 1977 conference was intended to
`seek solutions in spite of these difficulties:
`*to establish the sharing criteria for the bands 11.7-12.2
`GHz (in Regions 2 and 3) and 11.7-12.5 GHz (in Region 1)
`between the BSS and the other services to which these
`bands are allocated;
`* to plan for the BSS in the above-mentioned bands;
`* to establish procedures to govern the use of these bands by
`the BSS and by the other services to which these bands are
`allocated ...."
`
`TABLE I
`12-GHz FREQUENCY ALLOCATIONS
`
`GHz
`
`Allocation to Services
`
`Region
`
`Region 2
`
`Region 3
`
`11-7 - 12 5
`FIXED
`MOBIILE except
`aeronautical mobile
`BROADCASTING
`BROADCASTING-SATELLITE
`
`11-7- 12-2
`FIXED
`FIXED-SATELLITE
`(Space-to-Earth}
`MOBILE except
`aeronautical mobile
`BROADCASTING
`BROADCASTINS-SATELLITE
`
`11-7 - 12 2
`FIXED
`MOBILE except
`aeronautical mobile
`BROADCASTING
`BROADCASTINU-SATELLITE
`
`405BB 405BC
`
`405BA
`
`122- 125
`
`FIXED
`MOB1LE except aeronautical mobile
`B ROADCASTING
`
`405BA
`
`In the band 1 1.7-12.2 GHz in Region 3 and in the band 11.7-12.5 GHz
`405BA
`in Region 1, existing and future fixed, mobile and broadcasting services shall not
`cause harmful interference to broadcasting-satellite stations operating in accor-
`dance with the decisions of the appropriate broadcasting frequency assignment
`planning conference (see Resolution No. Spa2-2) and this requirement shall be
`taken into account in the decisions of that conference.
`
`405BB
`Terrestrial radiocommunication services in the band 11.7-12.2 GHz in
`Region 2 shall be introduced only after the elaboration and approval of plans for
`the space radiocommunication services, so as to ensure compatibility between the
`uses that each country decides for this band.
`
`405BC The use of the band 11.7-12.2 GHz in Region 2 by the broadcasting-
`satellite and fixed-satellite services is limited to domestic systems and is subject
`to previous agreement between the administrations concerned and those having
`services operating in accordance with the Table, which may be affected (see
`Article 9A and Resolution No. Spa 2-3).
`
`In accordance with this agenda, the Conference produced
`1) a Plan for broadcasting satellites in
`following:
`the
`Regions 1 and 3; 2) a set of principles to be used in imple-
`menting systems in the BSS and the FSS in Region 2, pend-
`ing the holding of a Regional Conference no later than
`1982";
`3) a method of making changes in the Plan; and 4) agree-
`ments on the levels of interference that could be produced
`to other services and in other Regions
`
`

`
`GOULD AND REINHART: 1977 WARC ON BROADCASTING SATELLITES
`
`173
`
`The fact that no plan for Region 2 was adopted at this
`conference was due largely to the opposition to such a plan by
`the United States, Canada, and Brazil. The view of these
`nations was that any plan adopted many years before the first
`satellite was to be designed and operated could neither be
`based on the actual characteristics of satellites that will be
`possible in future years, nor could it accurately reflect the
`actual communication requirements that would then exist.
`Therefore, any such plan would likely be inefficient and
`wasteful of the orbit and spectrum.
`Although Region 2 may itself adopt a rigid plan at the
`1982 conference to replace the present guidelines and prin-
`ciples, at least it is likely to be a better plan than the rest of
`the world has now, since the system parameters to be used in
`generating it could be based on advances in the technology in
`the intervening five years.
`
`GENERAL ASPECTS OF FREQUENCY SHARING
`
`Before discussing the subject of sharing further, it should
`be noted that there are several ways in which a band of fre-
`quencies can be shared between different services, or indeed,
`between different systems in the same service, according to
`which "dimension"-frequency, time
`or space-is divided
`among them.
`Spectrum Division
`or Suballocation: Each Service
`is
`assigned a different part of the band in which it is the
`primary service, and where other services can operate only
`if they do not interfere with the primary service. Systems
`can operate at the same time and place but not on the same
`frequency.
`Time Sharing: Each service is assigned a different operating
`period of day in which it is the primary service. Services can
`operate on the same frequencies and in the same geographic
`area but not at the same time.
`Geographic Sharing: Services are assigned geogaphically
`separate service areas. They can operate at the same time
`and frequency but not in the same place.
`Total Sharing: In some cases it is possible to share all three
`dimensions; services can operate on the same frequencies, at
`the same time, and in the same geographic area.
`Time and geographic sharing are much used in terrestrial radio
`and television broadcasting. Total sharing becomes possible
`with satellite systems because of the introduction of another
`spatial dimension on which sharing can be based: longitudinal
`position in the geostationary orbit.
`Whichever type of sharing is used, the basic objective is
`,simple: to keep mutual interference to acceptable levels on all
`links, of all systems, and in all services, to which the band is
`allocated. Each service seeks to get conference agreement on
`an initerference objective which specifies for that service the
`maximum allowable output signal degradation due to inter-
`ference. Such interference objectives establish the maximum
`allowable degradation from RF interference in much the same
`way that noise objectives specify the maximum allowable
`degradation due to thermal and other fonrs of noise. In adopt-
`ing these interference objectives an attempt is made to take
`into account the views of all the services involved. In some
`
`Fig. 2.
`
`Rain-climatic zones.
`
`zone I
`[3 Zone 2
`EM Zone 3
`m Zone 4
`Zone 5
`
`E
`
`8 1
`
`2
`
`9
`
`az
`0S
`
`10
`
`20 30405066077080990
`
`Fig.
`
`Elevation angle (degrees)
`Predicted attenuation values exceeded for not more than
`3.
`1 percent of the worst month (0.25 percent of the time) at 12 GHz
`in the rain-climatic zones indicted in Fig. 2. A: Rain-climatic zone
`1. B: Rain-climatic zone 2. C: Rain-climatic zones 3 and 4. D: Rain-
`climatic zone 5.
`
`cases, the objectives agreed on by a conference fall short of the
`values desired by a service, and compromises must be made.
`For analog telephone channels, the maximum interference
`power at the output of a single channel is specified in
`picowatts at a point of zero relative level, psophometrically
`weighted (pWOp). For television channels, the' subjective
`effects of interference on picture quality cannot be expressed
`easily in terms of an output signal-to-noise ratio, so the inter-
`ference objective is given directly in terms of the carrier-to-
`
`

`
`174
`
`IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY, VOL. EMC-19, NO. 3, AUGUST 1977
`
`interference power ratio which yields the specified quality.
`This value of minimum acceptable C/I is called the protection
`ratio, R. The protection ratio for a carrier modulated by a
`multiplexed telephone signal can, of course, be calculated by
`applying the receiver transfer characteristic to the output
`interference objective in picowatts.
`Expressing the interference objective in terms of the protec-
`tion ratio, the basic criterion for frequency sharing is that, for
`all links in all services
`
`C/I > R.
`
`(1)
`
`Specialized criteria applicable to the particular interference
`cases encountered in the 12-GHz band may be derived by
`substituting the applicable numerical value for R and express-
`ing C/I in terms of the equipment and geometrical parameters
`that characterize the systems involved. In this process, note
`that the basic criterion must be simultaneously met for both
`directions of interference (e.g., broadcasting satellites into
`terrestrial systems and vice versa). All sources of interference
`must be accounted for.
`When there are multiple interference entries, R and I refer
`to the total interference. Alternatively, (1) can be replaced by
`a set of simultaneous single-entry inequalities of the form
`
`C/hz >Ri
`
`(2)
`where Ii is the interfering power from the ith source, Ri is the
`corresponding single-entry protection ratio, and
`
`fl=I and R-1
`
`(3)
`
`Before reviewing the particular sharing criteria developed at
`the 1977 WARC, (1) or (2) can be used as a basis for cate-
`gorizing the general approaches that the system planner can
`use to make sharing easier and spectrum and orbit utilization
`more efficient. Either the right side of the inequalities can be
`made smaller, or the left side larger, or both.
`Reducing the right side involves manipulation of the signal
`characteristics that determine the value of the protection
`ratio R.
`These include the spectra of the wanted and
`unwanted carriers (as determined by the modulating signals,
`of modulation, modulation indices, and any signal
`type
`processing such as preemphasis, companding, energy dispersal,
`etc.), the frequency separation of the carriers and, of course,
`the allowable output signal degradation used in the definition
`of R. Table II lists some of the specific ways for reducing R.
`To increase the left side usually requires manipulating
`antenna patterns and/or system geometries to decrease the
`interference level, I, at the receiver input, since the wanted
`carrier power, C, is normally determined by the link power
`budget chosen to meet the noise objective for the "wanted"
`system. Table III lists some of the ways for reducing I.
`Once the signal and system characteristics have been
`chosen, the basic criterion can be converted into specific
`sharing criteria. Typically, they take the form of an upper
`limit on the power-flux density of the interfering signal as a
`
`TABLE II
`METHODS OF REDUCING R, THE PROTECTION RATIO
`
`E
`
`a
`
`*
`
`*
`
`Adopt higher interference objectives {for example, tradethermal
`noise for interference)
`
`Interleave carrier frequencies
`
`Use a "harder" modulation method and/or higher modulation
`indices
`
`Use energy dispersal on carriers
`
`TABLE III
`METHODS OF REDUCING I, THE INTERFERENCE
`
`Increase the propagation loss on the interference path (through larger
`separations between earth and terrestrial stations and/or through terrain
`or pit shielding)
`
`Improve transmitting antenna angular discrimination (to permit smaller
`service area separations)
`
`Improve receiving antenna angular discrimination (to permit smaller
`orbital separation between desired and undesired sateilites and smaller
`separations from terrestrial transmitters)
`
`Use shaped beams on satellite antennas
`
`Use orthogonal polarizations
`
`Use crossed-beam geometry
`
`Cluster similar satellites
`
`Reduce EIRP differences between Fixed and Broadcasting satellites
`
`*
`
`*
`
`*
`
`*
`
`*
`
`*
`
`*
`
`*
`
`function of its angle of arrival or a lower limit on the geomet-
`rical separation of stations. Such criteria can be of two distinct
`types:
`1) absolute limits, which the systems must satisfy without
`further negotiation; and
`2) "triggers" for a coordination procedure in which a more
`detailed interference analysis is made and system design and
`deployment can be negotiated between the countries having
`systems which could be affected.
`
`THE PLAN FOR REGIONS 1 AND 3
`
`The plan that was adopted for Regions 1 and 3 was based
`on the technical parameters shown in Table IV. The resulting
`plan made nearly 1000 frequency assignments distributed
`among about 250 service areas. The number of beams (or
`service areas) per country ranged from one (in the case of
`small countries such as Switzerland or Tunisia) to 35 (for the
`Peoples Republic of China). The number of channels per beam
`ranged from 1 to 8, with 4 or 5 being typical. The entire plan
`was based on the provision of "individual" reception. Note
`several important system characteristics on which the plan is
`1)
`satellites
`based:
`are spaced six degrees apart in the
`geostationary orbit; 2) occupied bandwidth is 27 MHz and
`adjacent channels are spaced 19.18 MHz apart, producing
`
`

`
`GOULD AND REINHART: 1977 WARC ON BROADCASTING SATELLITES
`
`175
`
`E
`
`c r
`
`a,
`:
`
`Relative angle )1/i0,
`
`I I,
`
`IF
`
`L9
`
`Curve A : Co-polar component for individual reception without sidelobe suppression
`Curve A': Co-polar component for community reception without sidelobe suppression
`Cross-polar component for both types of reception
`Curve B
`Minus the on-axis gain
`Curve C
`Copolar and cross-polar reference patterns for receiving
`Fig.
`4.
`antenna. Curve A: copolar component for individual reception
`without sidelobe suppression. Curve A: Copolar component for
`community reception without sidelobe suppression. Curve B: Cross-
`polar component for both types of reception. Curve C: Minus the
`on-axis gain.
`
`0
`
`-10
`
`-a-20 <tT T r xIrr
`
`cc
`
`A
`
`-50
`
`0.1
`
`0.2
`
`0.3
`
`1
`
`2
`
`5
`
`10
`
`20
`
`30
`
`50
`
`100
`
`TABLE IV
`TECHNICAL CHARACTERISTICS OF BROADCASTING
`SATELLITES ASSUMED FOR THE PLAN IN
`REGIONS 1 AND 3
`
`Characteristic
`
`Frequency Band (GHz)
`Channel Spacing (MHz)
`Minimum Channel Spacing on
`same antenna (MHz)
`Channel Grouping
`
`Guard bands (MHz) lower
`upper
`RF Channel bandwidth (MHz)
`Modulation & Signal Processing
`
`Energy Dispersal (KHz pk. to pk.)
`
`Polarization
`
`Cross-polarization component
`relative to co-polarized (dB)
`Thermal Noise Objective C/N (dB)
`
`Interference Objective, C/I (dB)
`co-channel
`adjacent
`Earth Station
`Figure of Merit, G/T (dB/K)
`Individual reception
`Community reception
`Antenna Beamwidth (degrees)
`Individual reception
`Community reception
`Reference Pattern
`Minimum angle of elevatiuii (deg)
`
`Value
`
`Reference*
`
`11.7-12b5
`19.18
`40
`
`channels within a single antenna beam, assigned
`within 400 MHz, where possible
`14,
`11
`27
`FM of video (plus sound on FM sub-carrier):
`Preemphasis as in CCIR Rec. 405
`600 (=22 dB reduction in power flux density
`in any 4 KHz band)
`CIRCULAR:
`"Direct" (RH or CW) and "Indirect" (LH or CCW(
`(same setses in different beams to same service
`area, where possible)
`-27 (Rain Zones 1 & 2)
`-30 (Rain Zones 3, 4 & 5) (see Figure 2)
`14 (99% of the worst month) (Propagation loss up to
`2 dB must be taken into account: see Figure 2 & 3)
`
`31 (99% of worst month)
`15 (99% of worst month)
`
`6
`14
`
`2 1=0.9 meter diam.)
`1 )=1.8 meter diam.l
`see Figure 4
`20-40 depending on terrain and rain climate
`
`-103
`-111
`3
`
`0.25
`
`3.5.1
`3.5.3
`
`3.5.2
`
`3.9.2
`3.9.2
`3.8
`3.1
`
`3.18
`
`3.2.2
`
`2.3
`
`3.3
`2.1.2.2
`
`3.4
`3.4
`
`3.6
`3.6
`
`3.7.1a
`3.7.1b
`3.7.2
`3.12
`
`3.16
`3.16
`3.17
`
`3.15
`
`Power Flux Density (dBW/m2)
`(Edge of coverage area) (99% of
`worst month)
`individual reception:
`community reception:
`Maximum difference between
`on-axis p.f.d. and edge of svc.
`area (dB)
`Maximum change during
`satellite lifetime (dB)
`Satellite
`Transmit reference pattern
`Half power beamwidtn (degrees)
`shape
`Gain (a and b are major and
`minor axis half-power
`beamwidths):
`Pointing accuracy (degrees)
`Angular rotation of elliptical
`beams (max.)(degrees)
`Satellite Spacing (degrees)
`Station-Keeping (N-S & E-W)
`(degrees)
`
`see Figure 5
`0.6 minimum required
`circular or elliptical
`27,843/ab
`
`+ 0.1
`
`2
`6
`+ 0.1
`
`Reference is to the indicated Paragraph of Annex 8 of the Final Acts of the Conference
`
`0.5
`
`3
`
`Roelative k
`o
`Reference patterns for copolar and cross-polar components
`Fig. 5.
`for satellite transmitting antenna. Curve A: Copolar component.
`Curve B: Cross-polar component. Curve C: Minus the on-axis gain.
`
`TABLE V
`EXTRACT OF "THE PLAN" FOR REGIONS 1 AND 3,
`GENEVA, 1977
`
`3.13.3
`3.13.2
`3.13.1
`3.13.1
`
`3.14.1
`
`3.14.1
`3.10
`3.11
`
`Cvuntry
`Num.
`Dobit
`symbol &
`IFRB Ser.
`Long.
`1 2
`API 0)99C
`23.0
`IFB 021C
`BEL l18C
`CYP t86C
`
`5.0
`
`-19 .0
`
`5.0
`
`Ch.
`No.
`3
`29
`
`29
`
`29
`
`29
`
`29
`
`Boresight
`Long. Lat.
`4
`
`Beam
`Ant.
`6W
`Mat. T Min.
`Orient.
`'6
`5
`11 .6 O..0.6
`0
`
`42.5
`
`24.5 -28.0
`
`3.1
`
`4.o
`
`5C .6
`
`33.3
`
`35.1
`
`0.8
`
`0.6
`
`1.7
`
`0.6
`
`0.6
`
`27.0
`
`167.0
`
`0.0
`
`12.6
`
`C.8
`
`C.6
`
`172.0
`
`Remarks
`
`9
`
`4
`
`EIRP
`
`PoI.
`7 8
`62.
`1
`
`2
`
`1
`
`1
`
`2
`
`64.2
`
`63.5
`
`63.7
`
`64.3
`
`some frequency overlap; 3) satellite antenna beamwidths need
`be no smaller than 0.60 or be shaped more specifically to the
`area they serve than is possible with an elliptical cross-section;
`4) satellite EIRP's are about 64 dBW; 5) earth stations use
`0.9-m antennas and have G/1s of 6 dB/K; and 6) antenna side-
`lobes must not exceed specified levels as shown in Figs. 4 and
`5. Both patterns are slightly better (that is, they require lower
`sidelobes) than the current CCIR reference patterns. A sample
`describing assignments to channel 29
`page of the Plan
`(12.26452 MHz) is reproduced as Table V. Note that on the
`eastern side of Region 2, satellites in the plan are positioned as
`far west as 370 west longitude.
`
`PLANNING FOR REGION 2
`As noted above, Region 2 adopted only interim provisions
`for the development of systems during the period until a
`
`MRC 209C
`
`-25.U
`
`NrM
`
`025b
`
`-l?.0
`
`SEN 222C
`
`-37.0
`
`UAE 274C
`
`UKR 063A
`
`YUG
`
`148C
`
`17.0
`
`23.0
`-7.11
`
`29
`
`29
`
`29
`
`29
`
`29
`
`7.4
`102.2
`-9.C
`17.5 -21.6
`
`29.2
`
`-14.4
`
`13.8
`
`53.6
`
`31.2
`
`18.4
`
`24.2
`
`48.4
`
`43.7
`
`2.7
`
`2.7
`
`1.5
`1.0
`2.3
`
`1.7
`
`1.5
`
`1.9
`
`1.0
`0.8
`1.0
`
`0.7
`
`43.0
`
`48.0
`
`139.0
`
`162.0
`172.0
`
`154.0
`
`2
`
`2
`
`2
`
`1
`
`2
`
`1
`
`o3.4
`
`64.8
`
`c3.7
`
`63.3
`
`64.6
`
`65.3
`
`DDR 216C
`
`-1.0
`
`HV0 107C
`
`-31.0
`
`ISL 049C
`ISR 1115
`
`KEN 249C
`
`MCO 116C
`
`MNG 248
`
`-31.0
`
`-13.0
`
`11.0
`
`-37.0
`s4.0
`
`-1.5
`
`-19.0
`
`34.9
`
`37.9
`
`52.1
`
`12.2
`
`64.9
`
`31.4
`
`1.1
`
`43.7
`46.o
`
`29
`
`29
`
`29
`
`29
`
`29
`
`29
`
`29
`
`1.4
`
`1.C
`
`C.9
`2.3
`
`0.6
`3.e
`
`1.1
`
`0.6
`
`0.6
`1.6
`
`0.6
`
`1.1
`
`29.0
`
`177.0
`
`117.0
`
`94.0
`
`0.0
`1o9.0
`
`1
`
`2
`
`2
`
`1
`
`1
`
`1
`
`64.1
`
`65.9
`
`63.9
`
`63.8
`
`62.5
`
`64.2
`
`

`
`176
`
`IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY, VOL. EMC-19, NO. 3, AUGUST 1977
`
`u~~~~~
`
`''
`
`-_
`
`0.1
`
`0.2
`
`0.3
`
`0.5
`
`1
`
`2
`
`3
`
`5
`
`30
`10
`50
`20
`Relative angle (/+ )
`
`100
`
`TABLE VI
`CHARACTERISTICS OF SYSTEMS IN REGION 2 THAT DIFFER
`FROM THOSE IN REGIONS 1 AND 3
`
`Characteristic
`
`Value
`
`Reference'
`
`R. F. Bandwidth (MHz)
`Individual reception
`Community reception
`Frequency Band (GHz)
`
`Guard Band (MHz)
`Lower
`Upper
`
`18
`23
`
`117 -12 2
`
`12
`9
`
`t/
`
`Earth Station half-power beamwidth
`(degrees)
`Reference pattern
`
`1.8 (=1 meter diam)
`see Figure 6
`
`Power Flux Density (dBW/m2)
`Individual reception
`
`-105
`
`3.8
`3.8
`
`3.9.2
`3.9.2
`
`3.7.1a
`3.7.2
`
`3.16
`
`Reference patterns for copolar and cross-polar components for
`Fig. 6.
`receiving antenna for individual reception in Region 2. Curve A: co-
`polar component without sidelobe suppression. Curve B: Cross-polar
`component.
`
`2)
`
`regional planning conference (to be held no later than 1982)
`establishes a detailed plan for the region.
`These interim provisions include segmentation of the orbit,
`specifying two orbital arc segments in which the BSS is
`pnmary: 750-100°W (750-95°W for
`the United States,
`Canada, and Mexico) and 140°-1700W. The FSS can use these
`segments on a secondary basis and all the rest of the orbit on
`a primary basis (with the BSS serving Region 2 secondary
`there) subject to certain significant limitations:
`1)
`provision must be made for the BSS between 550W and
`60°W to serve Greenland;
`guard segments as needed to protect the services from
`each other all come out of the FSS segments;
`3) FSS systems serving Region 2 from eastemrnost posi-
`tions in the orbit will receive interference from Region
`1 BSS serving larger, western European and western
`African service areas which, in some cases, exceed the
`allowable single-entry level.
`Prior to the 1982 Regional Planning Conference, all BSS
`systems are to be regarded as experimental and are without
`international recognition or protection. They must, in addi-
`tion, be operated in accordance with the sharing criteria and
`technical characteristics set forth in Annexes 8 and 9 to the
`Final Acts [1]. Differences in technical characteristics from those
`for systems serving Regions 1 and 3 (as shown in Table III)
`are given in Table VI. During this interim period, fixed-satellite
`systems can be installed using current notification and coor-
`dination procedures (Article 9A of the Radio Regulations).
`Article 12 of the Final Acts also directs administrations to
`submit their BSS service requirements to the IFRB before the
`1982 Regional Planning Conference.
`Annex 6 of the Final Acts sets forth the following planning
`principles to be applied in drawing up the plan for Region 2:
`equality for allocated services in Region 2;
`1)
`equal rights for services in the various regions;
`2)
`recognition of national requirements;
`3)
`equitable rights of access to the geostationary orbit
`4
`spectrum resource;
`
`Reference is to the indicated paragraph of Annex 8 of the Final Acts of the Conference
`
`NOTE: These are, essentially, interim provisions. The values eventually adopted by the 1982
`Regional Planning Conference may be different.
`
`5)
`6)
`
`flexible planning approach;
`efficient use of the geostationary orbit and the
`spectrum;
`consultations among administrations;
`7)
`individual reception.
`8)
`These principles do not imply recognition of systems existing
`prior to the implementation of a Region 2 plan.
`
`SHARING CRITERIA
`Referring to the international allocations shown in Table I
`and bearing in mind the regional planning differences, the
`sharing interfaces are as shown in the matrix of Table VII.
`Note that the interfering services are shown as columns; the
`as protected or interfered-with services are
`same services
`shown by the rows. The numbers in the boxes show the article
`and annex in the Final Acts-of the 1977 the WARC-BS in
`which the corresponding sharing criteria are described. Since
`we are considering only interference between services, the
`main diagonal is labeled NA = not applicable. The two direc-
`tions of interference between a given pair of services are
`located symmetrically about the diagonal. Elements labeled
`s'none" indicate that no criteria were developed. For example,
`only the FSS in Region 2 gets explicit interference protection
`from the Regions 1 and 3 BSS. Other services, including
`terrestrial services in Regions 1 and 3, must plan around the
`Regions 1 and 3 BSS that is, they must accept whatever
`interference broadcasting satellites in the plan may cause.
`While all services are protected against increases in interference
`caused by modifications to the plan, the broadcasting-satellite
`systems which are the subject of those modifications are not
`protected against any resulting increases in interference from
`existing or "notified" systems in other services. Finally, no
`criteria were determined for interference between the FSS and
`the terrestrial services because this was beyond the Terms of
`Reference of the conference. The interference protection
`requirements used as a basis for the sharing criteria are set
`forth in Annex 9. The values given there are shown here in
`Table VIII.
`
`

`
`GOULD AND REINHART: 1977 WARC ON BROADCASTING SATELLITES
`
`177
`
`TABLE VII
`SHARING CRITERIA GOVERNED BY THE FINAL ACTS*t
`INTERFERING SERVICE
`
`BSS
`REGIONS 1 & 3
`
`MOD.BSS"*
`REGIONS 1 & 3
`
`BSS
`REGION 2
`
`TERRESTRIAL
`FSS
`REGION 2 REGIONS 1,2&3
`
`BSS
`REGIONS 1 & 3
`
`MOD BSS"
`> REGIONS 1 & 3
`
`C BSS
`.. REGION 2
`
`O FSS
`cL REGION 2
`
`NA
`
`NONE
`
`NONE
`
`10/11
`
`4/1
`para
`
`NA
`
`4/1 para 2
`+Annex 10
`
`4/1 para 4
`+Annex 10
`
`TERRESTRIAL
`REGIONS 1, 2 & 3
`
`NONE
`
`4/1 para 3
`
`7/4
`
`7/4
`
`6/3
`
`NONE
`
`NONE
`
`NONE
`
`NA
`
`1219
`
`9/5
`
`12/9
`
`6/3
`
`NA
`
`NA
`
`NA
`
`NA
`
`Number above the traction bar refers to Articles of the Final Acts; numbers below, to its Annexes.
`MOD BSS indicates any proposed modification to the 1977 Plan must meet the sharing criteria set
`torth in the Article and Annex indicated.
`NA indicates not applicable.
`
`t
`
`TABLE VIII
`PROTECTION REQUIREMENTS FOR SHARING BETWEEN
`SERVICES IN THE 12-GHz BAND
`
`Wanted
`servicel)'
`
`Wanted
`signaI
`
`inter'-
`serv iJ c
`
`ns!n nterfering
`signall)
`
`Potect 3on. eequireflentS)
`
`a
`
`}
`
`e
`
`- Sngle
`
`BSS
`
`|7/F.
`
`BSS, FSS,F iS,
`
`V -
`'
`
`'
`
`)73 -C 5 dB )
`
`such modification would not cause significantly worse
`interference than the produced under the original plan;
`Article 5 describes the procedure for notification, examina-
`tion, and inclusion in the reference file of assignments to
`the broadcasting satellites of Regions 1 and 3. This proce-
`dure is begun by the administration that proposes to bring a
`satellite into operation not more than 3 years, nor less than
`90 days before the planned date;
`Articles 9 and 10 concern the limits of power-flux density
`that must not be exceeded in other regions. Specifically,
`Article 10 treats protection of the FSS in Region 2.
`
`INTERREGIONAL PROBLEMS
`sharing problem involving the
`interregional
`A serious
`geostationary orbital arc arose because the arc segment lying
`between longitudes of about 10°E and 50°W is useful to both
`Regions 1 and 2. Those longitudes are useful to broadcasting-
`satellite planners of Region 1 to avoid the eclipse problem
`there, while the fixed-satellite planners in Region 2 considered
`it equally important to be able to use positions as far east as
`10°E longitude to serve countries of South America, notably
`Brazil.
`The eclipse problem arises from the situation that broad-
`casting satellites will probably not be able to carry sufficient
`battery power to enable them to operate during the semi-
`annual eclipse periods, which are centered around local mid-
`night at the subsatellite point. Since most broadcasters want to
`after local midnight,
`provide programming at least until
`most administrations wanted