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DVB-T2, 32K SISO, not extended.

I've acquired P2 symbol, PRBS bits have matched with bits recovered from pilots. Then equalization was applied to all subcarriers. The constellation I've got looks exactly like rotated 16-QAM overlapped with non-rotated 64-QAM. On the picture: the red dots(-1,0) and (1,0) are for pilots, the blue dots for everything else, except tone reservation.

P2 constellation after equalization.  DVB-T2 Implementation guidelines (ETSI TS 102 831 V1.2.1 (2012-08)) clearly states:

Constellation rotation shall only be used for the common PLPs and the data PLPs and never for the cells of the L1 signalling.

  • What do I miss?

  • Also, can't find if there any subcarriers (cells) inverleaving applied to P2 symbol, can anyone explain this?

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Ok, question solved. I found out that indeed L1 pre/post constellations are not rotated.

The constellation above comprises:

  1. L1 pre (BPSK)
  2. L1 post (64-QAM)
  3. Data PLP from P2 symbol (rotated 16-QAM)

Also P2 cells are interleaved (ETSI EN 302 755 @ 8.5).

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