Certified Copy. Expert Report. Josef Stufler Ali Jaseb Gredinger Str Kinding. Textile shielding fabric marked with "WAVEBLOCK"

Transcription

1 Certified Copy Peter Pauli, Professor, MSc Neubiberg, 5 August 2007 University of the Federal Armed Forces Munich Werner-Heisenberg-Weg 39 page 1 Expert Report Ordering customer: Object under test: Test order: Electronic Wall Josef Stufler Ali Jaseb Gredinger Str Kinding Textile shielding fabric marked with "WAVEBLOCK" To measure the shielding effectiveness against electromagnetic waves within the frequency range 200 MHz to 10 GHz Examination principle: IEEE Standard , MIL Standard 285 and VG-Norm , Part 15 Date of measurements: 5 August 2007 Extent: 4 pages of text, 4 measuring records in appendixes 1 and 2 Result: As a result of the measurements it was established that the textile shielding fabric marked with WAVEBLOCK offers an excellent protection against electromagnetic waves within the measured range of MHz frequencies as well as GHz frequencies. It is therefore particularly suitable for protection of users from radiation emitted by mobile phones e.g. with the use of a bag for mobile phones which protects the user from radiation. It is also suitable for protecting magnetic stripe cards or cards with the SmartCard chip which could be damaged by too strong high-frequency fields. At distinctive mobile frequencies and depending on the respective polarisation, the sample exemplarily shows the following values: Polarisation referring to the oscillation : parallel to the oscillation orthogonal to the oscillation C network, TETRA, 450 MHz 45 db 45 db D network, 900 MHz 47 db 45 db E network, 1800 MHz 46 db 44 db UMTS, 2000 MHz 47 db 44 db Blue-Tooth, 2450 MHz 45 db 45 db For a better understanding: At 40 db, 99.99% of the radiant flux density is shielded and at 47 db these are even %. Thus, only 0.01% or 0,005% of the radiation comes through. These are extremely good characteristics for such textile product.

2 Peter Pauli, Professor, MSc Neubiberg, 5 August 2007 University of the Federal Armed Forces Munich Werner-Heisenberg-Weg 39 page 2 1. Preliminary Notes In order to determine the effectiveness of the WAVEBLOCK shielding fabric against electromagnetic waves, the measurements described under the section 2 were carried out. To facilitate the interpretation of the measurement curves, it may be of help to use the conversion table below: Here, the shielding effect, i.e. the attenuation of electromagnetic waves through the shield was determined in decibels ( = db). (see measurement curves) This decibel value indicates the lowering of the intensity of radiation as it travels through the protective fabric. The adjoining table allows the conversion of these logarithmic values into percentages. The radiant flux density which passes through the shield is generally used to assess the effectiveness of radiation protection as shown in this table. Conversion of the attenuation from db into % db transmission in % db transmission in % 0 100, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,001 Calculation of shielding effectiveness is carried out in db, from the radiation P 1 before the shield and P 2 behind the shield or with appropriate field strenghts, based on the following equations. Peter Pauli, Professor, MSc Neubiberg, 5 August 2007

3 University of the Federal Armed Forces Munich Werner-Heisenberg-Weg 39 page 3 2. Measurement Setup and Procedure Measurements were carried out according to requirements of the IEEE standard method which largely correspond to the specifications of the MIL-STD-285 military standard. The measurements were performed in the measuring area of the radar room at the University of the Federal Armed Forces Munich in Neubiberg on 5 August 2007 within the frequency range from 200 MHz to 10 GHz with linearly polarised waves. To this end, the test fabric as sketched in the figure below was placed in front of an 80cm x 60cm large orifice of the metal wall (surface 210cm x 200cm). Here it was made sure that the sample material was in contact with the entire surface of the metal plate of the measurement setup. There was no inter-system interference from external sources. In order to measure different polarisations, the measurement object was rotated in the polarisation axis by 90. rundherum HF-Absorber = all around highfrequency absorber Metall = metal Messobjekt= measurement object Empfangsantenne»innen«= receiving antenna "inside" Sendeantenne»außen«= transmitting antenna»outside«measurement setup for determining radiation protection After the calibration of the measuring track (without a test specimen to determine the 0 db transmission value), the shielding effectiveness of the measurement object with regard to the frequency range of the measuring antennas was carried out on two frequencies: Range I: 200 MHZ to 2200 MHz Range II: 1 GHz to 10 GHz The tips of the logarithmic-periodic measuring antennas were placed 40 cm before or 30 cm behind the test object relying on the MIL-STD 285. The following measuring equipment was used: Vectorial network analyser, type 360 (40 MHz to 18,6 GHz), Co. Wiltron Measuring antennas: Bilog antenna, type CBL 6112A (30 MHz to 2000 MHz9, Co. CHASE Measuring antennas: LogPer antennas, typer HL 025 (1 GHz to 18 GHz), Co. Rohde & Schwarz Documentation: laser printer Ecosys FS-1020D, Co. Kyocera Peter Pauli, Professor, MSc Neubiberg, 5 August 2007

4 University of the Federal Armed Forces Munich Werner-Heisenberg-Weg 39 page 4 3. Measurement Results and Evaluation of the Results In each appendix, the upper curve shows the "MHz range" ( MHz). The table below shows the results for the measurement of the frequency in GHz (1 GHz 10 GHz). This way, the important frequency range between 1000 MHz and 2000 MHz was measured twice with different antennas and individually calibrated. Good overlap of the measurement results of the two overlapping ranges shows good reproducibility and accuracy of the measurement results. As a result of the measurements it was found out that the shielding effectiveness of the textile shielding fabric marked with WAVEBLOCK within the measured MHz as well as within the GHz frequency range shows excellent results, however, the values slightly vary due to the polarisation of the measuring signal. Depending on the respective polarisation, the sample exemplarily shows the following values: Polarisation referring to the oscillation : parallel to the oscillation orthogonal to the oscillation C network, TETRA, 450 MHz 45 db 45 db D network, 900 MHz 47 db 45 db E network, 1800 MHz 46 db 44 db UMTS, 2000 MHz 47 db 44 db Blue-Tooth, 2450 MHz 45 db 45 db For a better understanding: At 40 db, 99.99% of the radiant flux density is shielded and at 47 db these are even %. Thus, only 0.01% or 0,005% of the radiation comes through. These are extremely good characteristics for such textile product. The results show that the shielding fabric marked with WAVEBLOCK is generally suitable for a very good protection from radiation emitted by mobile phones when used correctly. Possible applications are, i.a.: - use in cell phone bags for the protection of the cell phone user, - use of this fabric for the protection of magnetic stripe cards or cards with the SmartCard chips against damage by too strong high-frequency signals. Neubiberg, 5 August 2007 (signature) P. Pauli, Professor, MSc P. Pauli, Professor, MSc Appendix 1 to the Expert Report of 5 August 2007 Polarisation parallel to the oscillation

5 Measurement object: Shielding fabric WAVEBLOCK Upper measurement curve: frequency range 200MHz MHz Lower measurement curve: frequency range 1GHz - 10 GHz P. Pauli, Professor, MSc Appendix 2 to the Expert Report of 5 August 2007 Polarisation crosswise to the oscillation

6 Measurement object: Shielding fabric WAVEBLOCK Upper measurement curve: frequency range 200MHz MHz Lower measurement curve: frequency range 1GHz - 10 GHz

7 The credibility of the above copy is verified by signing this document. Beilngries, 30 August 2007 B Notary: (signature) Hereby, it is confirmed the authenticity of the above signature by...notary Günther Lindner... in...beilngries... and the authenticity of the above official seal. At the same time, it is confirmed that the above mentioned person is legally authorised to carry out official acts. Ingolstadt, on the...third of September... two thousand...seven... The president of the District Court Ingolstadt dr. Thomas Dickert (signature)