Plp parameters, Dtc-378 t2xpress – DekTec DTC-378 T2Xpress User Manual

Page 19

Page 19/27

DTC-378 T2Xpress Manual

Essential Tools for Digital-TV Professionals

February 2015

DTC-378 T2Xpress

7.10. PLP Parameters
Each row specifies the parameters for a PLP.

PLP parameter

Description

Unique identification of a PLP within a T2 system

Group

PLP Group ID. Identifies the PLP group with which the PLP is associated

Type

PLP Type: Common PLP, Data PLP Type1 or Data PLP Type 2

Mod

Modulation type used by the PLP: QPSK, 16-QAM, 64-QAM or 256-QAM

Cod

Code rate used by the PLP: 1/3, 2/5, 1/2, 3/5, 2/3, 3/4, 4/5 or 5/6

FEC

FEC type used by the PLP: 16K LDPC or 64K LDPC

HEM

High Efficiency Mode / Normal Mode selection. If checked, the PLP uses

High Efficiency Mode

NPD

Null Packet Deletion. If checked, the PLP uses Null Packet Deletion

ISSY

Input Stream Synchronization mechanism: None, Long (=3byte) or Short

(=2byte) field

BUFS

Maximum size of the requested receiver buffer to compensate for delay

variations. This variable uses the ISSY field and therefore it is only enabled if

the ISSY field is used

Design delay

Specifies the design delay in units of the elementary period T. When the

design delay is set to ‘0’, T2Xpress will automatically choose a valid design

delay.

IL type

Time IL Type

0: One Interleaving Frame corresponds to one T2-frame

1: One Interleaving Frame is carried in multiple T2-frames

IL length

Time IL Length

If the Time IL Type is set to ‘0’, this parameter specifies the number of TI-

block per Interleaving Frame

If the Time IL Type is set to ‘1’, this parameter specifies the number of T2-

frames to which each Interleaving Frame is mapped

Frame interv.

Frame Interval. Specifies the T2-frame interval within the super-frame for the

PLP

1st Frame

First Frame IDX. Specifies the index of the first frame of the super-frame in

which the PLP occurs

Rot

PLP Rotation. If checked, the PLP uses constellation rotation

In-band A flag

In-Band A Flag. If checked, the PLP carries in-band signalling information

Other PLPs

Other PLPs in the in-band signalling. If checked, all other PLPs are included

in the in-band signalling of the PLP. This option is only enabled if the In-

Band Flag is checked

In-band B flag

In-Band B Flag. Only used for DVB-T2 version >= version1.2.1

FF Flag