62.CISPR Pulse Response, HP 8590 EM-Series

62.CISPR Pulse Response ,

HP 8590 EM-Series

This is the only performance veri￿cation test that is performed with the EMC analyzer set in the EMC analyzer mode.

This CISPR pulse response measurement is made using a pulsed RF input signal rather than a pulse signal because the equipment is readily available, easily calibrated, and ￿exible in use. Pulsed RF setup considerations as well as the relationship between the two techniques are explained in Application Note 150-2.

The CISPR pulse response test measures the receiver quasi-peak detector receiver system's response to a pulsed RF input signal relative to that of a CW input signal and as a function of pulse repetition frequency. The output of the synthesizer/level generator is modulated by the pulse generator using the pulse modulator to yield the pulsed RF signal. The output of the pulse modulator

is connected to the input of the device under test (DUT) with a BNC cable through 3 dB of attenuation. This provides protection as well as a controlled source match. Amplitude accuracy is ensured by measuring the output signal of the 3 dB attenuation using the power meter with the pulse modulator dc biased to provide a CW signal. This measured CW amplitude also corresponds to the burst amplitude of the pulsed RF input signal when the pulse modulator is appropriately driven. The system is tested, through the 200 Hz, 9 kHz, and 120 kHz EMI bandwidth ￿lters with a pulse repetition frequency (PRF) corresponding to CISPR speci￿cations. The required CW amplitude for the tests is calculated based on the DUT's impulse bandwidth, the pulse width of the pulsed RF, and the CISPR speci￿ed spectral intensity.

Equipment Required

Pulse generator

Synthesizer/level generator

Power meter

Power sensor, 100 kHz to 1800 MHz

Attenuator, 3 dB

Modulator, TeleTech

Cable, BNC, 122 cm (48 in) (two required)

Adapter, Type N (f) to BNC (m)

Adapter, Type N (m) to Type N (m)

Performance Veri￿cation Tests 2-385