30 results about "Field strength meter" patented technology

A method and apparatus for detecting RF field strength. A field strength reference generator develops a field strength reference current as a function of a field strength of a received RF signal; and a field strength quantizer develops a digital field-strength value indicative of the field strength reference current. In one embodiment, detected field strength is used to dynamically vary the impedance of a tank circuit whereby, over time, induced current is maximized.

The present invention discloses a calibration method and system for high-intensity field sensors. The objective of the invention is to solve the problem that a standard field method is less likely to generate high field strength in a test area. The system of the invention comprises a transmitting antenna, a field strength meter, a reverberation chamber, a receiving antenna and a signal receiving system; the reverberation chamber comprises a horizontal agitator and a vertical agitator; the signal receiving system is used for measuring the field strength value of the receiving antenna. The method of the invention includes the following steps that: a calibrated field sensor is arranged in the field uniform area of the reverberation chamber, the transmitting antenna radiates electromagnetic waves into the reverberation chamber; the number of the times of the stepping of the horizontal agitator and the vertical agitator in one agitating cycle is set; when stepping occurs each time, the receiving field value of the field sensor and the aperture receiving power of the receiving antenna are measured; the average receiving field strength value of the field sensor and the average receiving field strength value of the receiving antenna in one agitating cycle are obtained; and the average receiving field strength value of the field sensor is compared with the average receiving field strength value of the receiving antenna, so that the field strength correction factor of the field strength sensor can be obtained. With the method and system of the invention adopted, the calibration of field strength sensors of which the field strength amplitude is above 200V / m can be realized.

Systems and methods for automatically triggering wireless power and data exchange between an external reader and an implanted sensor. The implanted sensor may measure the strength of an electrodynamic field received wirelessly from the reader and convey field strength data based on the measured strength of the received electrodynamic field to the reader. If the field strength data indicates that the strength of an electrodynamic field received by the sensor is sufficient for the implanted sensor to perform an analyte measurement, the reader may convey an analyte measurement command to the sensor, which may execute the analyte measurement command and convey measurement information back to the reader. The systems and methods may trigger the analyte measurement as the reader transiently passes within sufficient range / proximity to the implant (or vice versa).

The invention provides a redistribution method of a heavy doping boron silicon slice, and relates to a heavy doping boron silicon slice. The heavy doping boron silicon slice is placed on a tray, and then placed in a quartz chamber. The door of a screening box is closed. A seal mechanism is rotated and pressed tightly. The quartz chamber is vacuumized. Redistribution required gas is fed in the quartz chamber through a gas inlet and a gas outlet. The power is turned on. An electric field is applied in the space through an electrode slice. A radio-frequency power supply is started. The load matching is realized by an automatic matching unit, so that an induction coil produces a high-frequency changing magnetic field. A temperature sensor is started. The input power is adjusted to reach a required temperature by using the temperature indication of the temperature sensor. The heavy doping boron silicon slice is heated and the redistribution process starts. For ensuring operator safety, an electromagnetic shielding outer shell is arranged outside the electromagnetic induction coil. In the whole process of redistribution, an interference field strength meter is turned on to monitor field strength in a real-time manner, so that the field strength is within a relatively regulated range. The heating rate is fast, the cost is low, and the residual stress is effectively reduced.

The invention discloses a test device and a test method for broadband radiated immunity of a vehicle display device as well as application. The test device is provided with a radio frequency interference signal source, a first coaxial radio frequency switch, a low-frequency section power amplifier, a high-frequency section power amplifier, a forward power meter, a backward power meter, a second coaxial radio frequency switch, a third coaxial radio frequency switch, a first oriented coupler, a second oriented coupler, a fourth coaxial radio frequency switch, a 20MHz-200MHz low-frequency bi-conical antenna, a log antenna, a horn antenna, a field strength meter, a camera, a high-speed image acquisition card, a radio frequency switch control module, a serial port expansion card, a control host machine, a GPIB (general purpose interface bus) interface card and the vehicle display device. During testing, a broadband radio frequency interference signal is generated by a radio frequency interference signal source, the control host machine is used for judging the frequency section of the frequency of the interference signal, on the basis of the frequency section, the control host machine is used for controlling the radio frequency switch control module to automatically switch the coaxial radio frequency switches, so that the radio frequency signal source is enabled to be connected with the corresponding power amplifier and the corresponding antenna, and the forward power meter, the backward power meter and a video monitoring device are respectively used for the online monitoring of the testing field strength and the working state of tested equipment.