Page 708 - 5G Basics - Core Network Aspects

2 Transport aspects

(while it remains below the UPBOMASK) during the showtime by request from the FTU-O (under control of the VCE),
via OLR procedure Type 1, to improve upstream performance. The operator may also adjust the values of a and b in
the DPU-MIB and apply them via a new initialization.

7.3.2 PSD and PSD mask summary
A summary of the various PSDs and PSD masks used during the initialization and the showtime is presented
in Table 7-1.

Table 7-1 – Transmit PSD masks and PSDs used in this Recommendation
Parameter Description Notation

Limit PSD mask A PSD mask specified in [ITU-T G.9700] LIMITMASKds,
LIMITMASKus
DPU-MIB PSD mask A PSD mask specified by the operator intended to restrict the MIBPSDMASKds,
transmit PSD to levels below those allowed by the applicable MIBPSDMASKus
limit PSD mask.
Transmit PSD mask A PSD mask that is the minimum of: PSDMASKds,
1) the applicable LIMITMASK, PSDMASKus
2) the MIBPSDMASK, and
3) vendor-discretionary mask restrictions imposed by the
FTU-O and VCE.
UPBO PSD mask A PSD mask applicable for the upstream direction only that is UPBOMASK
calculated by the FTU-R as a function of the electrical length
of the loop (see clause 7.3.1.4).
STARTPSD mask A PSD mask limited to PSDMASK and further limited to STARTPSDMASKds,
TXPSDM_N inside the notched frequency bands (RFI and IAR STARTPSDMASKus
bands). In the upstream direction, also limited in accordance
with the UPBO requirements.
STARTPSD The PSD of the first signals transmitted by an FTU during the STARTPSDds,
first stage of the channel discovery phase of the initialization STARTPSDus

Channel discovery A PSD mask limited to PSDMASK and further limited to CDPSDMASKds,
PSD mask TXPSDM_N inside the notched frequency bands (RFI and IAR CDPSDMASKus
bands). In the upstream direction, also limited in accordance
with the UPBO requirements and by the PSD ceiling
(MAXMASKus).
Channel discovery The PSD of signals transmitted by an FTU during the later CDPSDds,
PSD stages of the channel discovery phase of the initialization. CDPSDus

PSD ceiling A PSD level, independent of frequency, used in determination MAXMASKds,
of CDPSDMASKus and V2PSDMASKds. MAXMASKus
V2PSD mask A PSD mask limited to PSDMASK and further limited to V2PSDMASKds
TXPSDM_N inside the notched frequency bands (RFI and IAR
bands) and by the PSD ceiling (MAXMASKds).
V2PSDds The PSD of signals transmitted by an FTU-O during the V2PSDds
VECTOR 2 stage of the channel discovery phase of the
initialization.
PRMPSDds The PSD of signals transmitted by an FTU-O during the PRMPSDds
PARAMETER UPDATE stage of the channel discovery phase of
the initialization.
MEDLEY reference A PSD mask limited to PSDMASK and further limited to MREFPSDMASKds,
PSD mask TXPSDM_N inside the notched frequency bands (RFI and IAR MREFPSDMASKus
bands) and by the PSD ceiling. In the upstream direction, also
limited in accordance with the UPBO requirements.

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