TEM小室在PCB板電磁兼容試驗中的應用

TEM Cell setups for repeatable measurements
For a test setup with more repeatable measurements than near field probes we can look to TEM Cells. A TEM (Transverse Electro-Magnetic) Cell (Figure 8) is a low cost alternative to measurements in an anechoic chamber. A TEM Cell is a near field device for radiated and immunity measurements. Because the device under test sits at a fixed location within the cell test results are easier to compare and repeat over time than with just a probe. While not directly correlated to far field chamber measurements, a TEM Cell takes repeatable measurements. When used with a complete EMI application tool, new designs can be compared to known good devices and custom limits can be established or developed from known standards that incorporate background emissions, limitations of the test setup, and correction tables. Used in this way, a TEM cell setup with RIGOL’s EMI Mode builds confidence in final compliance results by making it easy to compare good devices, failed devices, and new designs against corrected limit lines with appropriate margin. A repeatable test setup and RIGOL’s EMI Application mode provide an affordable test bed for EMI pre-compliance validation and comparison.