5results about "Shielding efficiency measurement" patented technology

To provide an electromagnetic wave absorber evaluation device and an electromagnetic wave absorber evaluation method capable of precisely evaluating behavior of an electromagnetic wave absorber for millimeter wave band or submillimeter wave band electromagnetic waves.SOLUTION: In an electromagnetic wave absorber evaluation device 1, width (a), height (b), and length L of a casing 2 for housing a board 3 having microstrip lines 4, 5 for inputting and outputting signals, and an evaluation frequency ft obtained by the following formula (1) satisfies the following formula (2) in a frequency domain of 20GHz or higher, wherein α is expressed by the following formula (5).SELECTED DRAWING: Figure 1

This application discloses an RF shielding device and its design method for pod testing, belonging to the technical field of pod testing. The RF shielding device includes: a shielding shell with a pod interface on its side wall, through which the pod antenna radome enters the shielding shell; an absorbing layer disposed on the inner wall of the shielding shell for absorbing the RF signal output by the pod and interference signals from outside the shielding shell; a test antenna disposed within the shielding shell for receiving the RF signal; and an RF interface disposed on the side wall of the shielding shell, connected to the test antenna for connecting to pod testing equipment. Compared to traditional anechoic chambers, this provides a convenient and safe radiation testing environment for pods, thus reducing the difficulty of pod radiation testing.

The invention discloses a shielding cable shielding effectiveness optimization method, which comprises the following steps: acquiring cable parameters, and establishing a three-dimensional geometric solid model of a high-voltage shielding cable based on the cable parameters; bending-deformation coupling modeling is carried out according to the three-dimensional geometric solid model, and deformation parameters are obtained through calculation; wherein the deformation parameter represents the microscopic geometric change of the shielding layer; evaluating the shielding effectiveness of the cable based on the deformation parameters; comparing the shielding effectiveness with a preset threshold value to determine a shielding effectiveness unqualified point; and optimizing the unqualified points of the shielding effectiveness. According to the method, the three-dimensional geometric solid model and the bending-deformation coupling model are established, the microstructure change of the shielding layer caused by deformation is obtained, and quantitative evaluation of the shielding effectiveness is realized based on electromagnetic simulation, so that unqualified points of the shielding effectiveness are optimized; the problem of shielding effectiveness attenuation caused by mechanical deformation in practical application can be effectively analyzed, and evaluation accuracy and optimization efficiency are improved.

An electromagnetic wave absorber evaluation apparatus including: a housing in which the electromagnetic wave absorber is allowed to be arranged, the housing being made of a conductive material with inner dimensions of a width a, a height b, and a length L, as b<a<L; a substrate arranged inside the housing; an input microstrip line and an output microstrip line formed on the substrate along a length direction of the housing and separated from each other in the length direction; and a signal inspecting unit capable of inputting an input signal having a frequency of 20 GHz or more into the input microstrip line and detecting an output signal output through the output microstrip line, in which an evaluation frequency ft obtained by the Formula (1) satisfies the Formula (2) in a frequency region of 20 GHz or more.

The invention provides a gradient magnetic field testing method and device for a magnetic shielding barrel. The gradient magnetic field testing device comprises a magnetic gradient testing unit, a supporting assembly and a connecting rod. An atom magnetometer can be nested in the magnetic gradient test unit to form a single magnetic field test unit. A plurality of magnetic gradient test units can be combined through the connecting rods to form a magnetic field gradient test array to adapt to the space in the shielding barrel. The magnetic field gradient test array can be connected with the supporting assembly, so that the magnetic field gradient test array is fixed in the shielding barrel and has mobility, and magnetic field distribution in the shielding barrel can be completely tested. According to the technical scheme, the technical problems that in the prior art, a visual large-range magnetic field imaging device is lacked, actual magnetic field gradient testing and compensation are lacked for a magnetic shielding barrel which is actually produced, processed and manufactured, and the space gradient in the magnetic shielding barrel can serve as an error term to be introduced into a magnetometer testing result are solved.