:FUNCtion:SNDRatio:RLMStandard

Command Syntax

:FUNCtionN:SNDRatio:RLMStandard {RLMA120 | RLMC94 | EYE}

Where N identifies one of sixty four {1:64} math functions that you can create. For example, :FUNCtion2.

Query Syntax

:FUNCtionN:SNDRatio:RLMStandard?

Description

For PAM4 and PAM3 signal type (see :FUNCtion:SIGNal:TYPE) SNDR measurements, this command selects the RLM measurement calculation algorithm to use.

This PAM4 symbol levels picture identifies the voltage levels used in the following equations.

RLM Standards
Parameter Available with signal types Description
RLMA120 PAM4

RLM (IEEE 802.3 Annex 120D) — The linearity is defined as a function of the mean signal level transmitted for each PAM4 symbol level. In the following equations, the term ES stands for the Effective Symbol Level.

RLMC94 PAM4, PAM3

RLM (IEEE 802.3 Clause 94). For PAM4:

For PAM3, the equation is the same except the V3 is changed to V2 and the division is by 2 instead of 3.

EYE PAM4, PAM3

Eye Linearity (CEI 4.0) — Eye linearity is the ratio of minimum eye amplitudes (in Volts) to maximum eye amplitudes (in Volts). For PAM4:

For PAM3, the equation is the same except the Eye 2 terms are omitted.