FEATURE MILITARY & DEFENCE Antenna port tests were previously
UK MILITARY EMC STANDARDS UPDATE
Def Stan 59-411 Issue 3 issued on 14 June 2019 provides the foundation for ensuring EMC in defence procurement. Pete Dorey, principal consultant at TÜV SÜD Ministry of Defence (MoD), highlights some key changes
P
art 1 Def Stan 59-411 Issue 3 Management and Planning addresses
EMC throughout the project lifecycle and defines the documentation such as control plans, test plans and test reports. For COTS/MOTS procurement a risk assessment procedure is provided that requires electromagnetic (EM) environment definition, evaluation of EMC compliance evidence (e.g. by gap analysis), determination of functional criticality of the equipment and platform and, mitigation of unacceptable risks by remedial design, installation methods and retest. The MoD’s gap analysis evaluation tool has now been made available via the EMC Test Laboratory Association. Part 1 Annex D has also been updated
to include the latest guidance on compliance with the EMC Directive 2014/30/EU. Testing can be minimised by establishing technical documentation to demonstrate where Def Stan 59-411 satisfies EMC Directive requirements via gap analysis and ensuring that the remaining unsatisfied requirements are tested using commercial standards. The manufacturer or supplier then makes a Declaration of Conformity and applies CE
Marking, with the option of assistance from an EMC Notified Body. Part 3 Test Methods and Limits for
Equipment and Sub Systems has been updated with new antenna port tests and changes to the radiated emission tests. Previously land service radiated
emission tuned antenna test DRE03 required the use of obsolete “Clansman” radio equipment in the frequency range up to 30MHz. Commercially available active rod antennas can now achieve the required sensitivity and DRE03 has been replaced with a “standard” radiated emission test DRE01. Test laboratories must therefore ensure they have active rod antenna that meet the performance requirement. The DRE01 test set-up for rod antenna has been amended and the rod antenna counterpoise must now be isolated from the ground plane bench, whereas previously it was bonded. However, there still remains the need
to use the BOWMAN VHF Combat Net Radio antenna for test DRE03.A over the frequency range 30MHz to 88MHz as this test is performed at 0.1m separation and it is not possible to achieve sufficient sensitivity with an active rod antenna at 1m separation.
considered outside the scope of Def- Stan 59-411, but emissions can cause significant interference issues. The new antenna port emission tests therefore assess the contribution of unintentional emissions from antenna feeder cables and antennas when the radio is transmitting, on standby or receiving. The tests also apply to antenna power
amplifiers. The new antenna port susceptibility tests assess the radio receiver performance in the presence of other transmissions. This is of increasing importance due to the MoD spectrum release and sharing initiatives, where military and civilian users must co-exist compatibly in the same frequency bands. Specialised test equipment is required for the antenna port susceptibility tests including low noise signal generators, filters and couplers. Part 4 applies to whole platform and
large system test and trials. New updates have been made to the Annex B Land Service radiated emission tests. This applies to Land Service military vehicle trials to ensure that communications performance is maintained when installed on the vehicle and while on the move, as well as ensuring that vehicle safety is not compromised by high-power radio transmissions. Radiated emission test DRE03 can be replaced with an equivalent test DRE01 using an active rod antenna over the frequency range 1.6MHz to 30MHz as long as precautions are taken to avoid overload of the antenna. Part 5 provides design guidance with
sections to cover air, land and sea applications, and addresses EMC fundamentals, equipment and platform design. There are no major changes to this part of the standard.
TÜV SÜD
www.tuv-sud.co.uk
20 JULY/AUGUST 2020 | ELECTRONICS
/ ELECTRONICS
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46
