| 摘要 |
Interrogation signal emitted by emitting/receiving means (1) is modulated so that they are decomposed in two frequencies, su as 125 kHz and 112,5 kHz. Transponder (2) answers by emitting identification signal at same frequencies. Identification signal frequencies present attenuation relative to interrogation signal frequencies. If intermediate emitting/receiving means (E1, E2) are inserted between car and transponder, relative attenuation will be modified. |
