General Description
R&S
®
CMW-KM645
8
User Manual 1173.9740.02 ─ 04
3 General Description
The "FM Stereo Radio Measurement" application (option R&S CMW-KM645) provides
transmitter (TX) tests on FM-modulated RF signals (called "FM signals" in the follow-
ing).
The tests cover the following FM signal properties:
●
RF carrier characteristics including the carrier power, frequency error, and the fre-
quency deviation due to a composite modulating signal ("multiplex deviation")
●
RF modulation characteristics including the frequency deviation due to the 19-kHz
pilot, the left and the right audio channels, and the pilot frequency error
●
Characteristics of the demodulated AF baseband signal including a Total Harmonic
Distortion (THD), Signal to Noise and Distortion ratio (SINAD), and Signal to Noise
Ratio (SNR) measurement
For background information on FM signals and conformance requirements refer to the
relevant standards, e.g.:
●
IEC 60315-4 (1997), Methods of measurement on radio receivers for various
classes of emission
●
ITU-R Recommendation BS.450-3, Transmission standards for FM sound broad-
casting at VHF
All "FM Stereo Radio" measurements are combined in a single, multi evaluation mea-
surement group.
The following sections describe how to configure and perform the "FM Stereo Radio
Measurement".
........................................................................................... 9
Limit Settings and Conformance Requirements
......................................................10
............................................................................................. 11
3.1 Test Setup
Connect the external RF signal source (mobile station, signal generator etc.) to one of
the bidirectional RF connectors on the front panel of the R&S
CMW.
See also: "RF Connectors" in the R&S
CMW user manual, chapter "Getting Started"
Test Setup
135-1095-0799
