Rohde and Schwarz FSL-K7 - AM/FM/φM Measurement Demodulator for FSL

The R&S FSL-K7 AM/FM/φM measurement demodulator converts the R&S FSL into an analog modulation analyzer for amplitude, frequency or phase-modulated signals. It measures not only characteristics of the useful modulation, but also factors such as residual FM or synchronous modulation.

Display and evaluation capabilities

• Modulation signal versus time
• Spectrum of modulation signal (FFT)
• RF signal power versus time
• Spectrum of RF signal (FFT versus max. 18 MHz)
• Table with numeric display of
  • Deviation or modulation depth, +peak, -peak, ± peak/2 and RMS weighted
  • Modulation frequency
  • Carrier frequency offset
  • Carrier power
  • Total harmonic distortion (THD) and SINAD

The digital signal processing in the R&S FSL, used in the analyzer mode for digital IF filters, is also ideally suited for demodulating AM, FM, or PM signals. The firmware option R&S FSL-K7 provides the necessary measurement functions.

The R&S FSL is equipped with a demodulator that is capable of performing AM, FM, and PM demodulation at a time. Additionally maximum, minimum and average or current values can be obtained parallelly over a selected number of measurements.

By sampling (digitization) already at the IF and digital down-conversion to the baseband (I/Q), the demodulator achieves maximum accuracy and temperature stability. There is no evidence of typical errors of an analog down-conversion and demodulation like AM to FM conversion and vice versa, deviation error, frequency response or frequency drift at DC coupling.