3GPP 23.501 v20.2.0 — the document's own text
5.7.3.6 Averaging Window
Taught in 14. What the network promises (The 5G system architecture, in depth), 5. The connection, and what is promised on it (The 5G system architecture, overview).
Each GBR QoS Flow shall be associated with an Averaging window. The Averaging window represents the duration over which the GFBR and MFBR shall be calculated (e.g. in the (R)AN, UPF, UE).
Every standardized 5QI (of GBR and Delay-critical GBR resource type) is associated with a default value for the Averaging window (specified in QoS characteristics Table 5.7.4.1). The averaging window may also be signalled together with a standardized 5QI to the (R)AN and UPF and if it is received, it shall be used instead of the default value.
The Averaging window may also be signalled together with a pre-configured 5QI to the (R)AN and if it is received, it shall be used instead of the pre-configured value.