1、 Reference number ISO 8729-2:2009(E) ISO 2009INTERNATIONAL STANDARD ISO 8729-2 First edition 2009-06-01 Ships and marine technology Marine radar reflectors Part 2: Active type Navires et technologie maritime Rflecteurs radars de marine Partie 2: Type actif ISO 8729-2:2009(E) PDF disclaimer This PDF
2、file may contain embedded typefaces. In accordance with Adobes licensing policy, this file may be printed or viewed but shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In downloading this file, parties accept therein t
3、he responsibility of not infringing Adobes licensing policy. The ISO Central Secretariat accepts no liability in this area. Adobe is a trademark of Adobe Systems Incorporated. Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF
4、-creation parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below. COPYRIGHT PROTECTED DOCUMENT I
5、SO 2009 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs member body in th
6、e country of the requester. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ii ISO 2009 All rights reservedISO 8729-2:2009(E) ISO 2009 All rights reserved iii Contents Page Foreword i
7、v 1 Scope . 1 2 Normative references . 1 3 Terms and definitions. 1 4 Construction 3 4.1 General arrangement 3 4.2 Structure and materials 4 4.3 Enclosed size of the reflector 4 4.4 Mass of the reflector. 4 5 Performance 4 5.1 Functionality 4 5.2 Reflecting pattern . 4 5.3 Time delay and stretching
8、. 5 5.4 Polarisation . 5 5.5 Stability and self-oscillation 5 5.6 Maximum power 6 5.7 Tolerance to a radar in close proximity 6 6 Environmental requirements . 6 7 Inspection and type tests. 6 7.1 Inspection 6 7.2 Testing . 6 7.3 Performance tests. 6 7.4 Environmental tests 12 7.5 Mechanical strength
9、 test 13 7.6 Electromagnetic emission tests 13 7.7 Electromagnetic immunity tests . 13 7.8 Spurious emissions tests 13 8 Installation . 13 8.1 Method . 13 8.2 Positioning 13 8.3 Mounting height 14 8.4 Mass . 14 8.5 Size. 14 9 Manual 14 10 Marking 15 Annex A (normative) Guidance notes for the install
10、ation of active radar reflectors 16 Annex B (normative) Test method for unwanted emissions of active radar reflectors 18 Bibliography . 23 ISO 8729-2:2009(E) iv ISO 2009 All rights reservedForeword ISO (the International Organization for Standardization) is a worldwide federation of national standar
11、ds bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organi
12、zations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in
13、 the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 %
14、of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 8729-2 was prepared by Technical Committee ISO/TC 8, Ships a
15、nd marine technology, Subcommittee SC 6, Navigation and ship operations. ISO 8729 consists of the following parts, under the general title Ships and marine technology Marine radar reflectors: Part 1: Passive type Part 2: Active type INTERNATIONAL STANDARD ISO 8729-2:2009(E) ISO 2009 All rights reser
16、ved 1 Ships and marine technology Marine radar reflectors Part 2: Active type 1 Scope It is recognised that small vessels, often made of glass fibre reinforced plastic (GRP), can be poor reflectors of radar signals. In situations where radar is the prime observation tool used by ships at sea, the In
17、ternational Maritime Organisation considers that it is essential that small vessels, considered in this context to be those under 150 gross tonnage, be equipped with a radar reflector to enhance their radar return and thus improve their visibility to radar. This International Standard specifies the
18、minimum requirements for a radar reflector intended to enhance returns from small vessels as required by IMO Resolution MSC.164(78). It provides the specification for the construction, performance, testing, inspection and installation of such radar reflectors. NOTE Requirements that have been extrac
19、ted from IMO Resolution MSC.164(78) Revised performance standards for radar reflectors are printed in italics. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated reference
20、s, the latest edition of the referenced document (including any amendments) applies. ISO 17025, General requirements for the competence of testing and calibration laboratories IEC 60945, Marine navigation and radiocommunication equipment and systems General requirements Methods of testing and requir
21、ed test results ITU-R SM.329, Unwanted emissions in the spurious domain ITU-R SM.1541, Unwanted emissions in the out-of-band domain 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 radar reflector device that is designed to enhance radar retur
22、ns from vessels with small radar cross section 3.2 active radar reflector device that receives, amplifies and retransmits a radar signal as a method of enhancing radar returns NOTE An active radar reflector is often also known as a radar target enhancer (RTE). ISO 8729-2:2009(E) 2 ISO 2009 All right
23、s reserved3.3 radar cross section RCS equivalent echoing area which is 4 times the ratio of the power per unit solid angle scattered in a specified direction to the power per unit area in a plane wave incident on the scatterer from a specified direction NOTE It is dependent on the radar operating fr
24、equency and the three-dimensional orientation of the reflector. Polarization of the transmitter and the received wave affects the effective radar cross section of the reflector. 3.4 azimuthal polar diagram polar diagram providing the RCS of the reflector with respect to its azimuthal angle NOTE Thes
25、e diagrams can be produced for any angle of heel. 3.5 null pronounced fall-off of RCS in the azimuthal polar diagram 3.6 stated performance level SPL performance level calculated from measurement data sets (i.e. azimuthal polar diagrams) taken during technical measurements of reflective performance
26、NOTE 1 SPL is the RCS value at which a null is 10 wide (see Figure 1). If there is more than one null with a width of at least 10, then SPL is the lowest such value. NOTE 2 If the azimuthal polar diagram does not show a null (as defined in 3.5) that is 10 wide, then the SPL is the RCS which is achie
27、ved over 280 of azimuth. ISO 8729-2:2009(E) ISO 2009 All rights reserved 3Key A azimuth R radar cross section aStated performance level. bNull width u 10. cSpacing between nulls W 20. Figure 1 Definition of stated performance level 3.7 self-oscillation phenomenon whereby the receive and transmit ant
28、ennas of an active reflector are unintentionally coupled, either inherently or by a reflecting surface closeby, so that feedback occurs between the two NOTE Devices that are self-oscillating are also said to be unstable. 3.8 saturation state whereby an active radar reflector is emitting the maximum
29、power of which it is capable NOTE 1 This power at which saturation occurs is known as the saturated power. NOTE 2 The distance from the interrogating radar at which saturation occurs is a function of the power of the radar, the total gain of the reflector and the maximum power of the reflector. 4 Co
30、nstruction 4.1 General arrangement The active radar reflector shall consist of a receive antenna (or antennas), an amplifier (or amplifiers) capable of operation across the X and S bands and a transmit antenna (or antennas). Typically there may also be an ISO 8729-2:2009(E) 4 ISO 2009 All rights res
31、ervedassociated control box whose function is to switch the device on and off and to indicate to the user that the device is working. 4.2 Structure and materials The materials used for the radar reflector shall be of sufficient strength and quality as to make the reflector capable of maintaining ref
32、lection performance under the conditions of stress due to sea states, vibration, humidity and change of temperature likely to be experienced in the marine environment. Use of ferrous metals should be avoided. 4.3 Enclosed size of the reflector The volume of the reflector should not exceed 0,05 m 3 .
33、 4.4 Mass of the reflector The reflector should weigh as little as practical in order to minimise its effect on the stability of small vessels. 5 Performance 5.1 Functionality The active radar reflector shall receive a radar pulse, amplify it and retransmit it. The output shall only be an amplified
34、version of the received pulse, without any form of processing except limiting. 5.2 Reflecting pattern 5.2.1 The radar reflector shall have a stated performance level of at least 7,5 m 2at X band (9,300 GHz to 9,500 GHz) and 0,5 m 2at S band (2,900 GHz to 3,100 GHz). The SPL shall be maintained over
35、a total angle of at least 280. The response shall, at the calculated SPL for each azimuthal polar diagram, not have any nulls wider than a single angle of 10, and not have a distance between nulls of less than 20. Nulls of less than 5 shall be ignored for this calculation. NOTE Typical azimuthal pol
36、ar diagrams for an active radar reflector in X band at 0 and 10 elevation are given in Figure 2. ISO 8729-2:2009(E) ISO 2009 All rights reserved 5Key A azimuth R radar cross section, expressed in m 2a0 elevation bstated performance level for 21,7 m 2c10 elevation dstated performance level for 7,5 m
37、2The 0 elevation response shows a calculated SPL of 21,7 m 3for 280 azimuth coverage and the response at 10 elevation is calculated at 7,5 m 3 , which is just compliant with respect to the minimum SPL requirement. These two plots also illustrate the expected antenna gain reduction with elevation cha
38、nge. Figure 2 Examples of typical RTE azimuthal polar diagrams and their associated SPL 5.2.2 For power-driven vessels and sailing vessels designed to operate with little heel (catamaran/trimaran), this performance shall be maintained through angles of (athwartships) heel 10 either side of vertical.
39、 For other vessels, the reflector shall maintain this performance over 20 either side of vertical. 5.3 Time delay and stretching The time delay and stretching of the output shall not exceed 10 % of the length of the received pulse or 10 ns, whichever is greater. 5.4 Polarisation The active reflector
40、 shall respond to radar using horizontal polarisation in both X and S bands. For S band, the active reflector may use circular polarised antennas for receiving and transmitting. 5.5 Stability and self-oscillation The active reflector shall be inherently stable and it shall not be possible for instab
41、ility to be induced under any conditions. Stability shall be demonstrated by the tests specified in 7.3.4 and 7.3.5. ISO 8729-2:2009(E) 6 ISO 2009 All rights reserved5.6 Maximum power The maximum power of the active reflector shall not exceed 10 W. 5.7 Tolerance to a radar in close proximity The ref
42、lector must be able to withstand a continuous pulse power density of 2 kW/m 2 . This is equivalent to a 25 kW radar, 1 s, with a 1,83 m antenna 1) at a range of 30 m. 6 Environmental requirements The active radar reflector shall meet the dry heat, damp heat, low temperature, solar radiation, vibrati
43、on, rain and spray and corrosion requirements of IEC 60945 where they are applicable. If the design of the active radar reflector system is such that some parts are intended to be installed in an exposed position and others in a protected position, then the tests to which each part shall be subjecte
44、d shall be those which apply to the intended position. 7 Inspection and type tests 7.1 Inspection A visual inspection shall be carried out to confirm that the construction and finish of the reflector is such that the unit is safe to handle. For example, burrs should be removed and, if applicable, wi
45、res fixed so that injury cannot occur during the handling of the reflector. 7.2 Testing Tests will normally be carried out at test sites accepted by the type test authority for these tests. General requirements for the competence of testing and calibration laboratories are given in ISO 17025. The ma
46、nufacturer shall, unless otherwise agreed, set up the equipment and ensure that it is installed in accordance with their installation requirements before type testing commences. 7.3 Performance tests 7.3.1 General The reflective performance tests shall be conducted in a free-field environment where
47、the background noise level has been reduced to the equivalent echoing area of 0,01 m 2or less at frequencies between 2,900 GHz to 3,100 GHz and 9,300 GHz to 9,500 GHz. Typically, a fully anechoic microwave test chamber, specified for up to 10 GHz operation, would be used for the conduct of these tes
48、ts. Before use, the reflector test range shall be calibrated using a precision sphere of known radar cross section. These tests may be carried out using a continuous wave (CW) or pulsed signal. CW signals are atypical of current magnetron radar but produce lower uncertainties in reflector testing. D
49、ue to the 100 % duty cycle of a non-fluctuating CW signal, the manufacturer should be consulted to ascertain the maximum time tests can be conducted and the duration of any rest period to allow for equipment under test (EUT) cooling. The tests should be carried out at both X band (9,410 GHz) and S band (3,050 GHz) with the same power density at the EUT turntable that was used for the chamber calibration. This power density should be at least 6 dB below the level required to saturate the EUT, unles