Codan Radio P25 Training Guide - Manual (Page 90)

TRAINING GUIDE | P25 RADIO SYSTEMS
Chapter 6: P25 Trunking Page 82
Figure 6-6: Multiple Block Trunking Structure (Unconfi rmed PDU)
PDU (Multi Block Trunking Message)
ISP or OSP Data
Header Block
12 Octet
Block 1
12 Octets
Block 2
12 Octets
Block 3
12 Octets
FS 48 bits NID 64
Trellis coded Header Block
196 bits
Trellis coded Optional Block
196 bits
Trellis coded Optional Block
196 bits
70 bits 70 bits 70 bits 70 bits 70 bits 70 bits 70 bits 70 bits
expand with status symbols
Status Symbols as required
2 bits after every 70 bits
Rate 1/2 Trellis
Encoder (196,96) Rate 1/2 Trellis Encoder
(196, 96)
Break into a header block
and up to 3 data blocks