Chapter 500

WCDMA ACPR and AltCPR measurements

Doug Stuetzle


Setups for the measurement of adjacent channel power ratio (ACPR) and alternate channel power ratio (AltCPR) are described.


Adjacent channel power ratio


Alternate channel power ratio




ACPR (adjacent channel power ratio) and AltCPR (alternate channel power ratio) are important measures of spectral regrowth for digital communication systems that use, for example, WCDMA (wideband code division multiple access) modulation. Both ACPR and AltCPR quantify the ratio of regrowth in a nearby channel to the power in the transmitted channel (Figure 500.1).

Figure 500.1 WCDMA ACPR Limits, Per 3GPP TS 25.104, Section

To measure ...

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