EN 14777:2004

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Space engineering - Multipaction design and testRaumfahrttechnik - Multiplication Konzeption und TestSystemes sol et opérations - Conception et test prenant en compte l'effet MultipactorSpace engineering - Multipaction design and test49.140Vesoljski sistemi in operacijeSpace systems and operationsICS:Ta slovenski standard je istoveten z:EN 14777:2004SIST EN 14777:2005en01-januar-2005SIST EN 14777:2005SLOVENSKI
STANDARD
EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 14777July 2004ICS 49.140English versionSpace engineering - Multipaction design and testSystèmes sol et opérations - Conception et test prenant encompte l'effet MultipactorRaumfahrttechnik (Engeneering) - MultipactionKonzenption und TestThis European Standard was approved by CEN on 29 April 2004.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the Central Secretariat or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36
B-1050 Brussels© 2004 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 14777:2004: ESIST EN 14777:2005

Multipaction background.28 A.1 Physics of multipaction.28 A.2 Other physical processes.29 A.3 RF operating environment.29 A.4 Parallel plate multipaction.35 A.5 Coaxial line multipaction.40 Annex B (informative)
Component venting.43 B.1 Introduction.43 B.2 Discharge dependence on pressure.43 B.3 Test example.43 B.4 Venting dimensions.44 B.5 Venting hole calculations.44 B.6 Payload vacuum.44 B.7 Venting model used.44 B.8 Pumping conductance of a venting hole.45 B.9 Ultimate pressure.46 B.10 Venting experiment.48 B.11 Venting guidelines.48 Annex C (normative)
Cleaning, handling, storage and contamination.50 C.1 Generic processes.50 C.2 Cleaning, handling and storage.50 C.3 Contaminants.52 Annex D (normative)
Electron seeding.55 D.1 Introduction.55 D.2 CW test.55 D.3 Pulsed test.55 D.4 Multi-carrier test.55 D.5 Types of seeding source.57 Annex E (informative)
Test methods.58 E.1 Introduction.58 E.2 General test methods.58 E.3 Transient tests methods.62 E.4 Test facility validation.69 Bibliography.70
Figures Figure 1 — Routes to conformance for single carrier.15 Figure 2 — Routes to conformance for multi-carrier case.18 SIST EN 14777:2005

1) ECSS-E-20-01 SIST EN 14777:2005

The components are well vented. 2 The RF paths contain or can contain dielectrics or other materials for which the multipaction performance is well defined. The components are well vented. 3 Any components not classified as Type 1 or Type 2. 4.6 Single carrier 4.6.1 General This sub-clause states the numerical values of the margins to be used for CW and pulsed systems. 4.6.2 Margins The margins shown in Tables 2 to 4 for the three different component types shall be applied. NOTE The margin is defined with respect to the peak operating power for the component. Table 2 — Margins applicable to Type 1 components Route Analysis margin (dB) Qualification test margin (dB) Batch acceptance test margin (dB) Unit acceptance test margin (dB) 1 8 - - - 2 - 6 - - 3 - - 4 - 4 - - - 3
Table 3 — Margins applicable to Type 2 components Route Analysis margin (dB) Qualification test margin (dB) Batch acceptance test margin (dB) Unit acceptance test margin (dB) 1 10 - - - 2 - 6 - - 3 - - 4 - 4 - - - 3
Figure 1 — Routes to conformance for single carrier SIST EN 14777:2005

Table 6 — Margins applicable to Type 1 multi-carrier components for single carrier threshold below equivalent CW peak power Single and multi-carrier margin with respect to equivalent P20 Route Analysis margin (dB) Qualification test margin (dB) Batch acceptance test margin (dB) Unit acceptance test margin (dB) 1 6 - - - 2 - 6 - - 3 - - 5 - 4 - - - 4 4.7.4 Route to demonstrate conformance a) The route to demonstrating conformance under multi-carrier multipaction conditions as illustrated in the flow diagram shown in Figure 2 shall be used. b) The unit shall not be accepted at each stage of the process unless 1) the relevant margins are satisfied, and 2) controls in the production process are such that adequate margins are carried through to the final components. NOTE The stages in the process are analysis, qualification tests and acceptance tests, where the latter can be either batch or unit tests. c) If any stage of the process is omitted, then it shall be assumed that the margins are not satisfied and the ‘no’ route in the flow diagram (see Figure 2) shall be followed. SIST EN 14777:2005

a Margin applicable to Type 1 multi-carrier components for single carrier threshold above equivalent CW peak power b Margin applicable to Type 1 multi-carrier components for single carrier threshold below equivalent CW peak power Figure 2 — Routes to conformance for multi-carrier case SIST EN 14777:2005

NOTE This can be accomplished using computer software from measurement on appropriate test pieces or estimated from the appropriate use of equivalent circuit models. A multipaction analysis cannot be performed without a good understanding of the electric fields within the component. 5.3 Critical region identification a) Any region where high voltages and critical gaps exist shall be identified. b) The most critical regions shall be located by considering their relevant gap voltages and frequency-gap products. c) Reference shall be made to the multipaction zones chart defined in Figure 3, which determines the multipaction regions in voltage/frequency-gap space for the relevant materials and geometries. NOTE For additional information, see A.4.2.6. d) The multipaction regions referred in c) above shall be subjected to analysis in order to calculate the predicted multipaction threshold. e) The analysis referred in d) above shall cover all frequencies that are expected for the component in service. SIST EN 14777:2005

Slope constants
(a) (b) (f × d)
Aluminium 40 27 1,5
Copper 54 54 1,0
Ag/Au 63 39 1,6
Alodine 74 74 1,5 Key U = Peak voltage across gap (V) (f ×××× d) GHz mm = Frequency gap product Figure 3 — The susceptibility zone boundaries for aluminium, copper, silver, gold and alodine 1200 5.4 Multipaction sensitivity analysis a) Having located and analysed the critical regions, a sensitivity analysis shall be performed to determine the sensitivity of the multipaction threshold to dimensional variation and changes in material properties.
b) The sensitivity analysis referred to in a. shall then be used to determine the correct degree of mechanical tolerance and process control to impose in cases where acceptance tests are not being performed on all flight units. SIST EN 14777:2005

b) The analysis shall demonstrate that the pressure within the vented component falls to below 1,5 × 10-3 Pa before RF power is applied, under both testing and in-orbit conditions. NOTE Annex B illustrates the type of analysis that can be performed. 5.6 Inspection The outputs from both the multipaction sensitivity analysis and the venting analysis shall be used when determining the inspection requirements to be imposed on the product during all stages of production. 6 Test conditions 6.1 Cleanliness a) Airborne particulate cleanliness class 8 as per EN ISO 14644–1, or better conditions, shall be maintained throughout the component assembly, test, delivery and post-delivery phases.
b) In addition, standard clean room practices for handling flight equipment and for general prevention of contamination, agreed with the customer, shall be strictly applied.
c) Protective covers to prevent the ingress of contaminants should be used.
d) Where surfaces are particularly vulnerable to contamination, specific cleanliness control measures should be applied. NOTE 1 For environmental contamination control of components and for preservation, packaging and dispatch of electronic components, see ESCC Basic Specification No. 24900 and ESCC Basic Specification No. 20600. NOTE 2 For additional requirements on cleanliness see Annex C. 6.2 Pressure a) Multipaction testing shall be performed at pressures below 1,5 × 10-3 Pa in the critical areas of the component. NOTE This can be achieved by providing an adequate combination of: — pressure in the vacuu
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