1. Chapter 10 Telemetry Downlink
Zodiac Data Systems

2. Presentation overview
Topics:
Telemetry downlink methods today
The new chapter 10 asynchronous packet downlink airborne method
Chapter 10 telemetry downlink packet format
Telemetry downlink filter possibilities
The ground segment

3. Telemetry Downlink Methods Today
Most Telemetry today utilizes IRIG 106, Class I or II, Chapter 4 PCM stream formats
Tedious job periodic sampling of asynchronous data and placing it into PCM Stream
It can be challenging and requires extensive testing
Repeated samples
Often requires excess bandwidth to insure data is not missed

4. Current Airborne System Architectures
Recorders
Recorders are typically used for capturing bus communications, video (HD/SD), high rate analog and output from FTI Encoders, buses (Total Data Capture).
Recording standard is in IRIG106 Chapter 10 Format
Encoders
Typically capturing transducers and selected data from busses for insertion into Time Division Multiplexed PCM Data Streams
Trend: Network output from Telemetry Encoders

5. Current Airborne System Architecture
Recorder
Total Capture
1553
Video
High Speed Analog
Asynchronous Serial
Ethernet
Parallel/Discrete
Chapter 10
Recording
PCM IRIG Ch4
Encryptor
Transmitter
Antenna
Time Division Muxed
1553
Video
Low Speed Analog
Parallel/Discrete
Other Data Types
Encoder
Recorder used for Post mission all data analysis
Encoder primarily used for Real Time TM Downlink, Analog sampling
Duplicate Interfaces for Recorder and Encoder !

6. Chapter 10 Asynchronous Packet Downlink Airborne Scenario
Quick-look and
real-time monitoring
1553
Video
High Speed Analog
Asynchronous Serial
Ethernet
Parallel/Discrete
Recorder
Chapter 10
Recording
PCM or Ethernet
Encoders
Analog
Discrete
Encryptor
Transmitter
Antenna
IRIG106 Ch10 packets inserted into a constant rate PCM Ch4 stream
Duplicate interfaces not required !

7. Interface Module Creates Class II PCM stream with IRIG 106 Ch10 Packets
Quick-look and
real-time monitoring
Traditional Chapter 4 PCM TM downlink
UDP
Selected Ch10 packets from any recorder data types
Transmitter
Constant Bit Rate
PCM Stream with self-correcting code
(Ch10 TMDL)
UDP data stream (e.g. IP cameras)
or other Video sources
Antenna

8. Multiplexing Packets into a Single Fixed Bit Rate PCM Steam
Ch10 Video
Packet
Ch 1 Ch
Packet
Ch 2
Fill Packet, Status Information
Ch10 TMDL does not require any programming assignment of data in the Ch4 PCM stream typically required for Encoders

9. (IRIG106 Standard Class II)
TM Downlink Format
First Header Pointer
Header
Frame
Sync Word
Frame
Sync Word
Fill
Ch10 Packet
Ch10 Packet
Minor Frame
(IRIG106 Standard Class II)

10. Low Latency Data Handling
Low Latency Packet mechanism helps inserting time critical data anywhere into the stream
Latency can be kept below 20ms for critical data
Typically 100 ms latency for non priority data
Low Latency Data FS
Pck #N FS
Pck #N FS LL FS
Pck #N
Pck #N
Transfer packets may overlap transfer frames

11. Protecting Structure Critical Elements
Frame headers, packet header data type and packet length are structural critical information
Transmission errors in these fields could multiply error rate
Extended Golay (24,12,8) coding: corrects 3 of 24 transmitted bits
Additional Optional Error Correction
In case of high error rate additional error correction technics can be used
Recommended method: Reed-Solomon error correction defined by CCSDS (223 data bytes + 32 parity symbols)
Allows to correct any 16 bytes in the 255 byte transmitted data + parity blocks
Interleaving of up to 8 Reed Solomon Block helps handling burst errors (one burst error is spread up to 8 RS blocks)

12. Lower Rate TM Downlink Filtering for Specific Data Types
PCM (complete minor frames)
MIL-STD-1553 (total bus)
ARINC-429 (All labels)
Ethernet (All messages)
HD video (compressed)
High bandwidth analog
PCM (selected words)
MIL-STD-1553 (selected messages)
ARINC-429 (selected Labels)
Ethernet (selected messages or data words)
Video (SD compressed or rate decimated HD)
Bandwidth limited analog
Aircraft Data Sources:
Ch10 TMDL PCM Down Link Stream:

13. PCM Filter Word Selection
Status display will show the new data rate

14. Video Bit Rate Decimation Multiple Rate Compression
HD High Bit Rate H.264 Video Ch10 Recording
On-Board
Video Camera
HD Video Interface
On Board High Rate Streaming
Frame Rate Decimation
and / or
HD to SD conversion
Packet Ch10 TMDL Interface
Low Rate PCM TM Downlink

15. Downlink of Filtered 1553 Data
All 1553 Message Ch10 Recording
MIL-1553 Interface
Packet
Ch 1
Packet
Ch 1
Packet
Ch 1 BC RT
UDP Broadcast of All Bus Data
(or Filtered, if selected so)
Selected 1553
Message Packets
Packet Ch10 TMDL Interface
Filtered
Ch 1
FilteredCh 1
Selected Messages
Fixed Bit Rate PCM

16. Airborne Processing Channel Concept
PCM Stream
Matrix Switch
Filter 1 2
Filter 2 3
All Data 1
Recording 1
Recording 2
UDP 1
UDP 2
TM Down 1
TM Down 2
Destinations

17. Quick-look and real-time monitoring:
Generic Air and Ground Diagram
Quick-look and real-time monitoring:
Network Data (e.g. IP cameras)
And other Video sources
Other Network data processing
Ch4 PCM
Ch10 TMDL stream
IRIG106 Ch10 UDP broadcast
Antenna
Ch4 PCM output
PCMs from encoders
Direct Video analysis

18. ZDS Ch10 TMDL Components

19. Ch10 TM Downlink Summary
Totally compatible with TM encryptor, decryptor, transmitters, receivers, bit syncs
Switching cost is low
Ch10 Telemetry greatly simplify TM downlink process
Minimal testing required to setup mission
Ideal for HD recording and SD Video downlink
Low latency is achievable

20. Thank you !