Codan Radio P25 Training Guide - Manual (Page 88)

TRAINING GUIDE | P25 RADIO SYSTEMS
Chapter 6: P25 Trunking Page 80
Figure 6-4: Trunking Signaling Block Structure
Figure 6-5: Trunking Signaling Block (TSBK)
TSBK (Single Block Trunking Message)
ISP or OSP Data
FS 48 bits NID 64 bits TSBK 196 bits
70 bits 70 bits 70 bits
expand with status symbols
Status Symbols (Unknown10) as required
2 bits after every 70 bits
Rate 1/2 Trellis
Encoder (196,96)
Null
42 bits
70 bits 70 bits
First Status Symbol
of OSP (last Status Symbol
of previous OSP) is 11
(used for Slotted ALOHA)
360 bits 37.5 ms (5 micro-slots)
70 bits
LB P Opcode
MFID
Bit 7 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6 Bit 0 Bit 1
Octet 0
Octet 6
Octet 5
Octet 4
Octet 3
Octet 2
Octet 1
Octet 9
Octet 8
Octet 7
Octet 11
Octet 10
CRC
Arguments
Optionally
Protected
Trunking Signal Block (TSBK)