SLS-CS_16-12 Terminology Used with Sliced Transfer Frames Fall Technical Meeting, Rome 17 to 21 Oct 2016 SLS-CS_16-12 Terminology Used with Sliced Transfer Frames V. Sank - NASA/GSFC/ASRC SLS-CS_16-12 Oct 2016 10/25/16

Code and Synch Pink, Sliced SMTFs CADU For the chapter on LDPC coding with unaligned Transfer Frames we initially, reluctantly, accepted the term CADU for a Transfer Frames preceded by an ASM. After the last meeting NASA started work on a new project and found a total mess with this term because all of the other system documents referred to the CADU rate as the rate at the channel level with all the coding. To avoid mistakes for that project we were forced to use the term CADU for the codeword/block. We are now suggesting use of an alternate term for the ASM with Transfer frame. We are asking the working group to select a term or pick one of the following suggestions. DTF Delimited Transfer Frame STF Synchronizable Transfer Frame SMTF Synch Marker with Transfer Frame other ? 1 of 11 SLS-CS_16-12 Oct 2016 10/25/16

CADU CCSDS 131.0-B-2 TM Synch and Channel Coding Blue Book Code and Synch Pink, Sliced SMTFs CADU CCSDS 131.0-B-2 TM Synch and Channel Coding Blue Book 8.1.2 CHANNEL ACCESS DATA UNIT The data unit that consists of the ASM and the Transfer Frame (if the Physical Channel is not Reed-Solomon, Turbo, or LDPC coded) or the Reed-Solomon Codeblock or Turbo or LDPC Codeword (if the Physical Channel is Reed-Solomon, Turbo, or LDPC coded) is called the Channel Access Data Unit (CADU). The Transfer Frame, Codeword, or Codeblock in the CADU may or may not be randomized. The current AOS Blue Book makes only this one mention of CADU. On next slide, the pink sheets propose a change. If the change is not accepted, the current statement needs to be corrected to say that the CADU is the various types of codeblocks with a preceding synchronization marker. … or the Reed-Solomon Codeblock or Turbo or LDPC Codeword preceded by a synch marker (if the Physical Channel is … Once corrected, no change is required for the case of sliced transfer frames. 2 of 11 SLS-CS_16-12 Oct 2016 10/3/16

the physical channel unit. 9.1.2 CHANNEL ACCESS DATA UNIT Code and Synch Pink, Sliced ASM + Transfer Frames Addition of chapter 8 on slicing causes the old chapter 8 to now be chapter 9. The following is the pink sheet proposal with last line not required if CADU used only for the physical channel unit. 9.1.2 CHANNEL ACCESS DATA UNIT The data unit that consists of the ASM and the Transfer Frame (if the Physical Channel is not Reed-Solomon, Turbo, or LDPC coded) or the Reed-Solomon Codeblock or Turbo or LDPC Codeword (if the Physical Channel is Reed-Solomon, Turbo, or LDPC coded) is called the Channel Access Data Unit (CADU). The Transfer Frame, Codeword, or Codeblock in the CADU may or may not be randomized. This Recommended Standard defines data unit called the Channel Access Data Unit (CADU) whose contents are as per attached table 9-1. The Transfer Frame, codeword, or codeblock in the CADU may or may not be randomized. NOTE – The term ‘CADU’ originated in reference [E3] and is now in established use, even though it may not be applicable to a channel. 3 of 11 SLS-CS_16-12 Oct 2016 10/25/16

Specific things to change if CADU is use for only for Code and Synch Pink, Sliced ASM + Transfer Frames Back Up Specific things to change if CADU is use for only for Physical Channel Data Unit (Partial List) 4 of 11 SLS-CS_16-12 Oct 2016 10/25/16

Code and Synch Pink, Sliced SMTFs No change required Code and Synch Pink, Sliced SMTFs 2.2.4 SYNCHRONIZATION This Recommended Standard specifies a method for synchronizing Transfer Frames using an Attached Sync Marker (ASM) (see section 9). The ASM may also be used for resolution of data ambiguity (sense of ‘1’ and ‘0’) if data ambiguity is not resolved by the modulation method used in the Physical Layer. This Recommended Standard also defines a Code Sync Marker (CSM) (see section 8) that, when used, may also be used for resolution of data ambiguity. The CSM is not used for synchronizing Transfer Frames. 5 of 11 SLS-CS_16-12 Oct 2016 10/25/16

Code and Synch Pink, Sliced SMTFs Small change required Code and Synch Pink, Sliced SMTFs 2.3.1 SENDING END Figure 2-2 shows the internal organization of the Synchronization and Channel Coding Sublayer of the sending end. This figure identifies functions performed by the sublayer1 and shows logical relationships among these functions. The figure is not intended to imply any hardware or software configuration in a real system. Depending on the options actually used for a mission, not all of the functions may be present in the sublayer. At the sending end, the Synchronization and Channel Coding Sublayer accepts Transfer Frames of fixed length from the Data Link Protocol Sublayer (see figure 2-1), performs functions selected for the mission, and delivers a continuous and contiguous stream of channel symbols to the Physical Layer. When LDPC encoding of a stream of SM + TFs Channel Access Data Units (CADUs), defined in 9.1.2, is performed, the sending end does codeword randomization and attachment of Code Sync Marker as described in section 8 and shown explicitly in figure 8-2. 6 of 11 SLS-CS_16-12 Oct 2016 10/25/16

Figure 2-2 Code and Synch Pink, Sliced SMTFs Original Figure 2-2 New Figure 2-2 in pink sheets Or stream of ASM with Transfer Frames when slicing used Remove word “Attached” and this applies to all cases Leave as in current blue book Figure 2-2 7 of 11 SLS-CS_16-12 Oct 2016 10/2/16

Code and Synch Pink, Sliced SMTFs CADU to SM+TF Code and Synch Pink, Sliced SMTFs 2.3.2 RECEIVING END Figure 2-3 shows the internal organization of the Synchronization and Channel Coding Sublayer of the receiving end. This figure identifies functions performed by the sublayer and shows logical relationships among these functions. The figure is not intended to imply any hardware or software configuration in a real system (e.g., some implementations perform frame synchronization before convolutional decoding when convolutional code rate 1/2 is used) . Depending on the options actually used for a mission, not all of the functions may be present in the sublayer. At the receiving end, the Synchronization and Channel Coding Sublayer accepts a continuous and contiguous stream of channel symbols from the Physical Layer, performs functions selected for the mission, and delivers Transfer Frames to the Data Link Protocol Sublayer. When LDPC decoding of a stream of CADUs SM+TF is performed, the receiving end does Code Sync Marker detection and codeword derandomization as described in section 8 and shown explicitly in figure 8-2. 8 of 11 SLS-CS_16-12 Oct 2016 10/25/16

Figure 2-3 Small change to figure Code and Synch Pink, Sliced SMTFs Original Figure 2-3 New Figure 2-3 Or stream of ASM with Transfer Frames when slicing used Leave as in current blue book Figure 2‑3: Internal Organization of the Sublayer at the Receiving End Figure 2-3 9 of 11 SLS-CS_16-12 Oct 2016 10/25/16

Code and Synch Pink, Sliced SMTFs CADU to SMTF below Code and Synch Pink, Sliced SMTFs Input Transfer Frames Stream of SMTFs (input to the Slicer) Information Blocks (Input to Encoder) Encoded Blocks i.e. LDPC codewords (Encoder Output) Encoded Symbols with CSM to Physical Layer Transfer Frame Synchronization Marker (ASM 32 bits) M bits k bits n bits Code Frame Synchronization Marker (CSM) CSM length depends on code rate. m*n bits m*n bits An LDPC codeblock may contain one or more Codewords. m=2 shown here. Figure 8-1 Transfer Frames Sliced to form Codeblocks   10 of 11 SLS-CS_16-12 Oct 2016 10/25/16

Code and Synch Pink, Sliced SMTFs CADU to SM+TF Code and Synch Pink, Sliced SMTFs 11 of 11 SLS-CS_16-12 Oct 2016 10/25/16