？Why is SEA greater than SER not necessarily indicating that the shielding mechanism is mainly absorption, but rather depends on whether A is greater than R?
SEA: Single Event Anomaly (SEA) refers to any unexpected or anomalous behavior in an electronic device caused by the impact of a single energetic particle, such as a proton or heavy ion. This impact can disrupt the normal operation of the device, causing it to produce incorrect results or malfunction temporarily. SEA is a broad term that encompasses various types of effects, including Single Event Upsets (SEUs), Single Event Transients (SETs), and Single Event Functional Interrupts (SEFIs). Yes in brooder sense it can be used as Judging electromagnetic shielding mechanism because if system shielding is properly implemented for given system this kind of impact should affect the system. Where as SER stand for Single Event Rate (SER) is a measurement of the rate at which single energetic particle events occur, causing anomalies or upsets in electronic devices. This term is often used to quantify the susceptibility of a device to radiation-induced effects. A higher SER value indicates a higher likelihood of such events occurring,
Indeed, you are correct that SEA (Shielding Effectiveness of Absorption) and A (Absorption coefficient) do not correspond to the same underlying mechanisms in electromagnetic wave shielding. This discrepancy arises from the variations in parameter definitions employed by researchers. For instance, in most literature, SEA and SER (Shielding Effectiveness of Reflection) are defined for the purpose of balancing the equation SET = SER + SEA, without offering substantial insights into the absorption and reflection phenomena of electromagnetic waves.
SET= 10log(T) power transmitted in decibels scale
SER= 10log(1-R) power not reflected
SEA= 10log(T/1-R)= 10log(T)-10log(1-R), which i dont know represents what power.
In the context of isotropic materials, the S-parameters obtained from a Vector Network Analyzer (VNA), particularly S11 and S21, serve as adequate descriptors to quantify the shielding performance of a material. These parameters encapsulate the reflection, absorption, and transmission characteristics of the shield. Notably, SER is typically expressed as 10log(1-R), representing the power that is not reflected so its whether absorbed and/or transmitted through the material.
However, the parameters R (S11^2) and T (S21^2) encompass all the necessary information concerning absorption, reflection, and transmission. This comprehensive representation holds true whether these parameters are presented in linear scale or the decibel scale.
In my opinion SE results should always be given in negative values, which represents loss mechanism instead of positive values which shows the gain of power (log of values >0 and
The acronym SEA stands for Absorption, Reflection, and Multiple Reflections. These are the three main mechanisms of electromagnetic interference (EMI) shielding. A is not SEA because it is not a mechanism of EMI shielding.
- Absorption: This is the process by which electromagnetic waves are converted into heat energy by the shielding material.
- Reflection: This is the process by which electromagnetic waves are bounced off the surface of the shielding material.
- Multiple reflections: This is the process by which electromagnetic waves are reflected multiple times between the shielding material and the object being shielded.
The effectiveness of an EMI shielding material is determined by its ability to absorb, reflect, and multiple reflect electromagnetic waves. The material with the highest shielding effectiveness will have a high absorption coefficient, a high reflection coefficient, and a high multiple reflection coefficient.
A is not a mechanism of EMI shielding because it does not involve the absorption, reflection, or multiple reflection of electromagnetic waves. It is possible that A could be a factor in EMI shielding, but it is not a mechanism in itself.
Here are some examples of materials that are used for EMI shielding:
- Metal foils, such as copper and aluminum
- Metal meshes
- Carbon fiber composites
- Absorbing materials, such as ferrites and carbon-loaded plastics
The choice of shielding material will depend on the specific application and the frequency range of the EMI that needs to be shielded.
The acronym SEA stands for Scattering, Emission, and Absorption. These are the three main mechanisms of electromagnetic interference (EMI) shielding.
A is not included in SEA because it is not a mechanism of EMI shielding. Attenuation is the reduction in the strength of an electromagnetic field as it propagates through a medium. It is a property of the medium, not a mechanism of shielding.
The three mechanisms of EMI shielding are:
- Reflection: This is the most common mechanism of EMI shielding. It occurs when an electromagnetic wave encounters a surface with a different electrical conductivity than the surrounding medium. The wave is reflected back into the medium, away from the shielded object.
- Absorption: This occurs when an electromagnetic wave interacts with the atoms or molecules of a material. The wave's energy is converted into heat, which is dissipated by the material.
- Multiple reflection: This occurs when an electromagnetic wave is reflected multiple times between two surfaces. This can further attenuate the wave's strength.
The most effective EMI shielding mechanism depends on the frequency of the electromagnetic waves being shielded. For example, reflection is more effective at shielding low-frequency waves, while absorption is more effective at shielding high-frequency waves.
In summary, A is not included in SEA because it is not a mechanism of EMI shielding. The three mechanisms of EMI shielding are reflection, absorption, and multiple reflection.
- Badges
- Science topic
- Similar topics
- Engineering
- Materials Engineering
- Powders