R&S CMW-KM5 Series, Руководство пользователя

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LTE Multi Evaluation Measurement
R&S
®
CMW-KM5xx/-KS5xx
510 User Manual 1173.9628.02 ─ 16
● Spectrum Emission Mask ......................................................................................515
● ACLR Limits .......................................................................................................... 516
● Power Dynamics Limits .........................................................................................517
3.2.5.1 Modulation Limits
All modulation limits can be configured per modulation scheme.
Fig. 3-8: One node per modulation scheme
The individual modulation limits are described in the following sections.
3.2.5.2 Error Vector Magnitude
A poor modulation accuracy of the UE transmitter increases the transmission errors in
the uplink channel of the LTE network and decreases the system capacity. The Error
Vector Magnitude (EVM) is the critical quantity to assess the modulation accuracy of
an LTE UE.
According to 3GPP, the EVM measured at UE output powers ≥ −40 dBm and under
normal operating conditions shall not exceed 17.5 % for QPSK-modulated signals and
12.5 % for 16-QAM-modulated signals.
The EVM limits can be set in the configuration dialog, depending on the modulation
scheme and along with limits for the other measured quantities.
Fig. 3-9: Limit settings for QPSK
Characteristics Refer to 3GPP TS 36.521 V10.3.0, section... Specified limit
EVM (RMS) 6.5.2.1 Error Vector Magnitude (EVM)
6.5.2A.1 Error Vector Magnitude (EVM) for CA
≤ 17.5 % (QPSK)
≤ 12.5 % (16-QAM)
tbd (64-QAM)
3.2.5.3 Frequency Error Limits
According to 3GPP, the UE modulated carrier frequency shall be accurate within ±0.1
ppm, compared to the nominal carrier frequency. The frequency error can be set in the
configuration dialog, depending on the modulation scheme.
General Description
深圳德标仪器
135-1095-0799