In comparison to a conventional EMI receiver the measurement performed by the TDEMI Measurement System the measurement time is reduced by a factor up to 4000.Depending on the applied IF filter bandwidth, in detail the measurement is speed up by a factor of 100 for an IF filter of 1 MHz, 1000 for an IF filter of 120 kHz and by a factor of 4000 for an IF bandwidth of 9 kHz.

The TDEMI inherent real-time digital signal processing eliminates the drawbacks of past FFT-based emission measurement systems. Real-time signal processing allows to continuously evaluate the signal by the applied detector. The main difference to conventional EMI receivers is the processing of several thousand frequencies in parallel, by a bank of IF filters and a corresponding number of parallel detectors. This is performed via high-speed digital circuits providing a calculation performance of about 100 gigamultiplications per second.

The digital signal processing (DSP) unit enables the TDEMI to perform the measurement at 4096 frequencies in parallel and to apply the detectors at all theses frequencies at the same time getting the spectrum of the received EMI signal at 4096 frequencies in one shot.By providing this technology, a full quasi-peak measurement up to 1 GHz performed with the TDEMI takes only up to two minutes. This fact totally eliminates the necessity of prescans. For the full frequency range, the calculation is performed sequentially in 8 bands. A bandwidth of 162.5 MHz is processed in real-time by the short-time fast Fourier Transform (STFFT).

Beside the receiver mode, comparable to the user interface of a conventional test receiver, as the user is familiar with, the TDEMI Measurement System brings the weighted spectrogram mode as a unique feature to the user where a full gapless view allow the user to debug the EMI signals in full gapless real-time. In the weighted spectrogram mode the CISPR bandwidths are available as well as the peak, average and rms detector. So, the weighted spectrogram mode is a very helpful tool for online EMC debugging.