Method and device for non-contact detection of external electric or magnetic fields

A sensor for use in a device for non-contact detection of an external field in the vicinity of an electric wire, the sensor comprising:

• a substrate carrying a delay line formed by a transducer arrangement on the substrate to define a wave channel for the wave propagation through the substrate;
• and
• a field transformer operable to concentrate the external field of a given voltage to thereby produce an increased intensity of the field within the delay line exposed to an increased intensity field in a known proportion, the increased intensity field directly affecting a velocity of the wave propagating within the delay line;
• wherein the transducer arrangement is capable of being actuated by an interrogation signal to generate said wave propagating through the wave channel and capable of converting the wave into an output response signal, said wave channel being exposed contactlessly to action of the increased intensity field created by said field transformer and proportional to the external field to be measured, which effects a change in the velocity of the wave propagation through the substrate said output response signal produced by the passive unit bent thereby informative of said external field.

A sensor for sensitive detection or external fields, the sensor being mountable at a spot where an external field is to be detected and comprising:

• a substrate made of a material capable of transporting therethrough a wave sensitive to said external field,
• a first delay line provided on said substrate to form a first wave channel for said wave's propagation contactlessly exposed to action of the external field, said first delay line comprising a first transducer arrangement capable of being actuated by a certain interrogation signal to generate said wave propagating through the first wave channel and capable of converting the wave into a first output signal;
• and
• a second delay line provided on said substrate to form a second wave channel for said wave's propagation, said second delay line comprising a second transducer arrangement capable of being actuated by a certain interrogation signal to generate the wave propagating through the second wave channel and capable of converting said wave into a second output signal;
• wherein said second wave channel is screened from the external field and has the length differing from that of the first wave channel to ensure a phase shift between the first output signal and the second output signal;
• the first and the second delay lines of said sensor are connected in parallel to provide an output response signal formed by superposition of said first and second output signals and being thereby informative of the external field.

A sensor for use in a device for non-contact detection of an external field by positioning the sensor at a spot where the external field is to be detected, the sensor comprising:

• a delay line, which is to be exposed contactlessly to action of the external field and is formed by a transducer arrangement that is provided on a substrate made of a material capable of transporting therethrough a wave sensitive to said external field, and defines a wave channel for the wave propagation through the substrate, the transducer arrangement being capable of being actuated by an interrogation signal to generate said wave propagating through the wave channel and capable of converting the wave into an output response signal, said external field affecting a change in a velocity of the wave propagation, said output response signal being thereby informative of said external field;
• and
• a field transformer operable to increase intensity of a field directly affecting the velocity of the wave propagation within the channel, as compared to the external field intensity, according to a known proportion, said field transformer being composed of two capacitors of different values of a capacity and a distance between the capacitor plates, such that the capacitor of a smaller capacity has a smaller distance between its plates, as compared to the other capacitor, the two capacitors being connected in parallel and being mounted at said spot where the external field is to be detected, the capacitor of the smaller capacity enclosing said delay line in a dielectric space between its place, the inner field of said capacitor of the smaller capacity affecting the velocity of the wave propagation through the channel.

A sensor for use in a device for non-contact detection of an external field by positioning the sensor at a spot where the external field is to be detected, the sensor comprising:

• a delay line, which is to be exposed contactlessly to action of the external field and is formed by a transducer arrangement that is provided on a substrate made of a material capable of transporting therethrough a wave sensitive to said external field, and defines a wave channel for the wave propagation through the substrate, the transducer arrangement being capable of being actuated by an interrogation signal to generate said wave propagating through the wave channel and capable of converting the wave into an output response signal, said external field affecting a change in a velocity of the wave propagation, said output response signal being thereby informative of said external field;
• and
• a field transformer operable to increase intensity of a field directly affecting the velocity of the wave propagation within the channel, as compared to the external field intensity, according to a known proportion, said held transformer comprising a metal element having a part thereof formed with a sharp edge, the field transformer serving as a concentrator of the external field, which is to be detected, within the delay line, when said metal plate is located in said spot so as to extend predominantly along the external field, and said sharp edge is located in the close vicinity of the delay line.