Sensor and method for operating sensor

A sensor, comprising:

• a substrate;
• an antenna pattern formed in a spiral shape on the substrate and configured to receive a radio signal from an external device so as to transmit a digital signal to the external device;
• a first electrode and a second electrode formed on the substrate and spaced apart from each other in parallel and configured to sense a measurement value representing a change in inputted alternating current power corresponding to a change in impedance by a sensing target material being brought into contact therewith;
• a circuit wiring formed to be connected to each of the first electrode and the second electrode;
• and
• an element bonded to the antenna pattern and the circuit wiring,
• wherein the antenna pattern, the first electrode, the second electrode, and the circuit wiring are formed of a same material and form a same layer, and
• wherein the element generates the alternating current power with the radio signal to supply the alternating current power to the first electrode and the second electrode through the circuit wiring, and generates the digital signal corresponding to the measurement value to transmit the digital signal to the external device through the antenna pattern.

A sensor, comprising:

• a substrate;
• an antenna pattern formed in a spiral shape on the substrate and configured to receive a radio signal from an external device so as to transmit a digital signal to the external device;
• a first electrode and a second electrode formed on the substrate and spaced apart from each other in parallel and configured to sense a measurement value representing a change in inputted alternating current power corresponding to a change in impedance by a sensing target material being brought into contact therewith;
• a circuit wiring formed to be connected to each of the first electrode and the second electrode;
• and
• an element bonded to the antenna pattern and the circuit wiring,
• wherein the element comprises:
• a communicator receiving the radio signal from the antenna pattern and supplying the digital signal to be transmitted through the antenna pattern;
• a power generator generating direct current power with the radio signal;
• and
• a controller woken up by the direct current power to convert the direct current power into alternating current power so as to supply the converted direct current power to the first electrode and the second electrode, and when the sensing target material is brought into contact therewith to thereby supply the digital signal to the communicator, generating the digital signal corresponding to at least one of ion concentration representing water quality of the sensing target material or salinity of the sensing target material according to a measurement voltage corresponding to an impedance change between the first electrode and the second electrode.

A method for operating a sensor, the method comprising:

• generating direct current power with a radio signal by receiving the radio signal from an external device;
• determining whether the radio signal is a signal requesting measurement of the ion concentration representing water quality of a sensing target material or a signal requesting measurement of salinity of the sensing target material, by being woken up by the direct current power;
• supplying a first driving current to a first electrode and a second electrode to sense a first measurement voltage corresponding to an impedance change of the first electrode and the second electrode to which the sensing target material is brought into contact with when the radio signal is determined to be the signal requesting measurement of ion concentration;
• determining whether the first measurement voltage satisfies a set ion reference voltage;
• and
• transmitting a first digital signal corresponding to the ion concentration calculated by applying the first measurement voltage to a set first logarithmic function to the external device when the first measurement voltage satisfies the ion reference voltage.