| Presentation | 2012-12-14 Electric Field Strength Estimation Near Half-wavelength Dipole Antennas Based on Wave Impedance Masaru Nakayama, Takehiko Kobayashi, |
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| Abstract(in Japanese) | (See Japanese page) |
| Abstract(in English) | A simplified equation for calculating electric field strength, based on the formula of free space propagation loss, has been widely used for electromagnetic applications. This equation has also been applied to the calibration of electric field probes, which has been specified in various standards, such as ISO/TR 10305-1, ISO/TR 10305-2 and IEEE Std. 1309. It is, however, valid only in the far field region. It is well known that the far field distance is given by λ/27〓, where λ is the wavelength. This formula, however, gives a distance where the magnitudes of three terms-electrostatic, induction, and radiation fields-are equal. The lowest test frequency specified in ISO 11452-2 is 80 MHz (A = 3.75 m) and the test distance is 1m, which slightly exceeds A/2ir toward to the far field. The accuracy attained by the conventional equation to calculate the field strength deteriorates at this marginal distance. In this report, a new equation for calculating the electric field strength is proposed, embracing the effects of variations in space impedance expressed by Pade approximation of the half-wavelength dipole antenna. Numerical results yielded by the conventional and proposed equations were compared with the experimental data measured in a radio anechoic chamber. Substantial improvement in accuracy was achieved with the proposed equation. |
| Keyword(in Japanese) | (See Japanese page) |
| Keyword(in English) | Electric field strength / near field / far field / radiated immunity test / electric field probe / Pade approximation |
| Paper # | EMCJ2012-90 |
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| Conference Information | |
| Committee | EMCJ |
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| Conference Date | 2012/12/7(1days) |
| Place (in Japanese) | (See Japanese page) |
| Place (in English) | |
| Topics (in Japanese) | (See Japanese page) |
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| Registration To | Electromagnetic Compatibility (EMCJ) |
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| Language | JPN |
| Title (in Japanese) | (See Japanese page) |
| Sub Title (in Japanese) | (See Japanese page) |
| Title (in English) | Electric Field Strength Estimation Near Half-wavelength Dipole Antennas Based on Wave Impedance |
| Sub Title (in English) | |
| Keyword(1) | Electric field strength |
| Keyword(2) | near field |
| Keyword(3) | far field |
| Keyword(4) | radiated immunity test |
| Keyword(5) | electric field probe |
| Keyword(6) | Pade approximation |
| 1st Author's Name | Masaru Nakayama |
| 1st Author's Affiliation | Wireless Systems Laboratory Tokyo Denki University() |
| 2nd Author's Name | Takehiko Kobayashi |
| 2nd Author's Affiliation | Tokyo Denki University |
| Date | 2012-12-14 |
| Paper # | EMCJ2012-90 |
| Volume (vol) | vol.112 |
| Number (no) | 361 |
| Page | pp.pp.- |
| #Pages | 6 |
| Date of Issue | |