A method, system and apparatus for compensating for non-ideal isotropic behavior of a field probe are disclosed. A method includes, during a calibration procedure, for each of a plurality of positions of the field probe relative to a source, each position denoted by a set of angles (θ, ϕ), performing the following steps: measuring a field by the sensors of the probe, storing the measurements and the set of angles (θ, ϕ) for each measurement, computing a correction factor for the set of angles (θ, ϕ) based on the measurement, and storing the correction factors. During a measurement procedure, each sensor measures a component of the field. A set of angles is determined based on the sensor measurements, and a correction factor is determined based on the set of angles. The correction factor may then be multiplied by the sensor measurements to obtain the corrected field measurements.

The focus of the teachings is on using Compact ferrite antenna to detect the motion of metal objects using a very low frequency (VLF) square wave, propagated between a pair of compact ferrite-particle dielectric-core RWA antennas in free space. The two salient features in the signal are observed; both of which are characteristic of Brillouin-precursor propagation: (1) a temporal Bessel-like waveform; and (2) an algebraic, rather than exponential, attenuation with distance over three meters. The key element teaching shows pair of source and detector antenna enables the detection of metals (weapon gun, knife) on a person or package between the ferrite- particle dielectric-core antennas- source (S) and detector (D) pairs or arrays of S-D tractor. The detection consisted of a change in the amplitude of the Bessel-like waveform of the received signal for security system to detect weapons.

A photonic Rydberg atom radio frequency receiver includes: an integrated photonic chip; an atomic vapor cell; and a receiver member including: a photonic emitter; probe light reflectors disposed on the atomic vapor cell; and coupling light reflectors disposed on the atomic vapor cell such that the pair of coupling light reflectors is optically opposed across the interior vapor space and receives and reflects the coupling laser light so that the coupling laser light is reflected between the coupling light reflectors multiple times in the interior vapor space of the atomic vapor cell.

A sensor receiver may include a Rydberg cell configured to be exposed to a radio frequency (RF) signal, and a probe source configured to generate a plurality of spaced apart pulsed probe beams within the Rydberg cell. The pulsed probe beams may be offset in time from one another. A plurality of excitation sources may be coupled to the Rydberg cell. A detector may be positioned downstream from the Rydberg cell.

In a method of atomic electrometry, EIT spectroscopy is performed on host atoms of an alkali metal in a vapor cell. The EIT spectroscopy indicates a resonant energy of a probed Rydberg state of the host atoms. The vapor cell is exposed to an ambient electric field. A shift in the resonant energy as indicated by the EIT spectroscopy is observed and interpreted as a measurement of the ambient field. During the measurement of the ambient field, a bias electric field is generated inside the vapor cell by shining light into the vapor cell from a light source situated outside of the cell. The bias field is useful for increasing the sensitivity of the measurement.

A near-field testing method proposed in the present invention includes steps of: in a selected coordinate system, controlling a motion device to cause random relative movement of the DUT and the probe to generate multiple random test points, determining one or more postures of the probe, and obtaining the electromagnetic field coefficients corresponding the postures of the probe respectively; obtaining the measured values of the electromagnetic field signals collected by the probes, and obtaining a set of measured values; according to the set of measured values and the electromagnetic field coefficients according to the Lorenz reciprocity theorem in electromagnetism, and determining the electromagnetic field coefficients through convex optimization; obtaining, according to the electromagnetic field coefficients, the far field pattern of the DUT or the electric field and/or magnetic field at any point outside the DUT.

A measurement system and method tests for spurious emissions included in a signal transmitted from a mobile terminal in a shorter time than before. The system includes: a band division unit for dividing the measurement frequency band into a plurality of divided bands; a first spurious measurement control unit which causes a measurement device to measure the spurious emissions of the signal to be measured in each divided band and the peak power of the spear in each divided band; and a first pass/fail determination unit that determines whether or not pass determination criteria is satisfied. The first pass/fail determination unit determines whether the peak power does not exceed the threshold of the pass determination criteria in each divided band. The threshold value of the pass determination criteria is lower than the threshold of the standard determination criteria defined by the 3GPP standard.

There is provided a test apparatus that measures transmission characteristics or reception characteristics of a DUT having an antenna under test, and includes an anechoic box, a posture changeable mechanism 56, a first test antenna 6a and a second test antenna 6b, for measuring the transmission characteristics or the reception characteristics of the DUT, a reflector that reflects a radio signal radiated by the first test antenna and converts the radio signal into a plane wave radio signal, and a movable antenna mechanism 60 that moves a position of the second test antenna such that the radio signal is transmitted to or received from the DUT installed in a far field at a plurality of angles of arrival, with reference to a radio-wave arrival direction from the first test antenna.

An electromagnetic wave measurement point calculation device of the present invention is an electromagnetic wave measurement point calculation device that is configured to calculate a plurality of measurement points of an electromagnetic wave set on a surface surrounding a radiation source of the electromagnetic wave. The electromagnetic wave measurement point calculation device includes an arithmetic processing unit configured to calculate a measurement interval between a first measurement point and a second measurement point adjacent to the first measurement point using a correction coefficient determined according to the first measurement point and execute an electromagnetic wave measurement point calculation process for sequentially calculating the plurality of measurement points in a measurement range.

According to one embodiment, a detection apparatus includes a pair of conductors configured to detect an electromagnetic wave occurring due to a discharge phenomenon in a target apparatus, wherein the pair of conductors are arranged in a near field region of the target apparatus in which the electromagnetic wave occurs.