1. Networked Audio
V+ and VComm
April 25, 2018

2. Agenda VComm Overview DIS/HLA Primer (Section 1)
How To Use VComm With V+ (Section 2)
Inside VComm (Section 3)
Important Issues to Remember (Section 4)
Questions and Answers
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3. VComm Overview
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4. VComm Overview (What is VComm?)
Networked Audio Component of V+
Uses DIS, HLA, and VoIP Protocols
Connects simulators via network
Simulate Radios Over Network
Provide intercoms, radio simulation, etc.
Interoperates with ASTi and others
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5. VComm Overview Continued
Can Be Used With Any Windows XP
Need sound and network device (card)
Works on laptops, desktops, etc
Unlimited number of radios and operation (sold separately)
Not credit based
Add on to V+
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6. VComm Overview Continued
VComm is Networked Audio
For local audio use SMx or other means
VComm Could Be Used for Local Communications
Inefficient since it uses network sockets
VComm and SMx Can Be Used Together
SMx uses virtual WI and WO, well suited for VComm Sierra
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7. DIS/HLA Primer
(Section 1)
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8. DIS/HLA Primer DIS HLA Distributed Interactive Simulation
High Level Architecture
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9. DIS/HLA Primer Continued
DIS in Wide Use
Military exercises
Virtual flag
Several hundred participants
SimPhonics systems play prominent role
Interoperable with ASTi, Plexus and emDee
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10. DIS/HLA Primer Continued
IEEE a standard
Distributed network for simulation interoperability
DIS in wide use
HLA less prominent but newer
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11. DIS/HLA Primer (DIS Versions)
IEEE
First IEEE Standard
IEEE a-1998
Second IEEE Standard
1278.1a-200x (Draft 13)
Under development
SimPhonics leading Radio Tiger Team effort
SISO PDG
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12. DIS/HLA Primer Continued (DIS Versions)
IEEE a-1998
Latest IEEE standard
Added Intercom PDUs (ICS)
ICS PDUs are not being used
1278.1a-200x
Improving plug and play capability for radios
Encourage vendors to interoperate
Fix bad sections in standard
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13. DIS/HLA Primer Continued
DIS Protocol Based on PDU/IP
All communication is via PDUs
PDU Families
Entity Information/Interaction
Warfare
Logistics
Simulation Management
Emission Regeneration
Radio Communications
Entity Management
Minefield
Synthetic Environment
Simulation Management with Reliability
Information Operations
Live Entity
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14. DIS/HLA Primer Continued
Relevant PDUs to VComm
Entity State
Used only for entity attach (more later…)
This means that all entity PDUs must be inspected if entity attach is being used
Radio Communication PDUs
Transmitter
Signal
Receiver
Intercom signal (IEEE a 1998 only)
Intercom control (IEEE a 1998 only)
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15. DIS/HLA Primer Continued
Radio Communication PDUs
Transmitter
Convey information about a simulated transmitter, on/off, type, secure equipment, etc.
Signal
Carries actual digitized audio data (voice)
Receiver
Conveys information about simulated receivers. This is not a widely used PDU, although SimPhonics does implement this PDU (possibly the only vendor)
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16. Transmitter and Signal PDUs
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17. DIS/HLA Primer Continued
Publish and subscribe mechanism
Much more efficient
Single process called RTi handles all interactions
At one time in the past, all DOD sites were mandated to be HLA compatible…(did not happen)
Difficult to setup and use
Low interoperability in industry
FOM
Federate Object Model
All applications must use same FOM
Most popular is RPR FOM 1.0
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18. DIS/HLA Primer HLA Versions Original version known as HLA 1.3
Developed by DMSO – public distribution
Has since been handed to industry and is no longer avail.
Current IEEE 1516 standard
HLA 1.3 still prominent
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19. How To Use VComm With V+ (Section 2)
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20. VComm DIS Radios DIS Protocol Based on PDU/IP Defined Requirements
All communication is via PDUs
Defined Requirements
Interoperability requirements
Voice quality & networking issues
Configure VComm
Create .VNE file
Build V+ Application
Reuse existing, or create new model
Monitor System
Debug, resolution of problems
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21. Interoperability Issues
Interoperability Requirements
If interaction with other vendor radios
Determine their needs
Compression scheme
Signal PDU length
Model fidelity – frequency match
Otherwise, no worries
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22. Voice Quality Sample Rate
Best Voice Quality When:
16,000Hz sample rate
No compression scheme (PCM)
Longer signal PDU lengths (1048)
Only Works When You Have This Freedom
Not interoperating
Network Bandwidth is available
8000Hz Most Common
Meets basic DIS requirement
Default VComm setting
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23. Voice Quality Continued
Compression Schemes
1 = mu-law, 2:1
2 = CVSD, 16:1 (MIL STD 188)
3 = ADPCM, 4:1
4 = 16-bit PCM (Big Endian), 1:1
5 = 8-bit Linear PCM, 1:1
6 = VQ, variable comp., (not supported in VComm)
7 = CVSD CCTT, 16:1
8 = bit GSM0, variable comp., (currently in devel.)
9 = 0.7-bit GSM0, variable comp., (currently in devel.)
100 = 16-bit PCM (Little Endian), 1:1
Only Mu-Law Required to be Compliant with (Current) DIS Standard
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24. Voice Quality Continued
Signal PDU Length
Any length will work with VComm, but
No specification requirement
VComm and ASTi use 480
Best to use other vendor’s settings
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25. VComm Network Topology Network Issues
Broadcast
Simple to configure, inefficient
Unicast
Point to Point
Multicast
Difficult to configure, efficient, becoming standard method of DIS networking
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26. Configuration
Network Topology
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27. Configuration Continued
Default port is 3000
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28. Configuration Continued
Specification version should not matter, but, some exercise filters require certain versions…
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29. Configuration Continued
HLA Setup
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30. Configuration Continued
Terrain Server Setup
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31. Build V+ App Select Existing Design Explore
C:\Program Files\VPLus\VPLus Samples\VComm
“VComm Radio.des”
Should not have to change anything
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32. Build V+ App Continued
Frequency
Push-To-Talk
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33. Build V+ App Continued
Antenna Location
Exercise ID
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34. DIS IDs If IDs are Left at Zero Otherwise, you must specify ID’s
VComm generates an ID based on IP address (e.g., generates an ID of 100/33/1/x
Otherwise, you must specify ID’s
Difficult configuration management
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35. Setting Compression Scheme
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36. Antenna Location Three Ways to Set Antenna Location
Hard code the X,Y,Z inputs with constants
Connect inputs to another computer (Host)
Attach the radio to an existing network entity
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37. Antenna Location Continued
Entity Attach
Allows VComm to attach to an existing entity on network
Must know the entity ID
Use Object 2017
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38. DIS/HLA Setup
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39. DIS/HLA Setup Continued
Each VComm Radio is Independent
Simultaneous use of DIS/HLA
“Send To Network” static data determines DIS/HLA network selection
Can use both!
“Send To Network” settings
0 - off (no packets will be sent)
1 – DIS
8 – HLA
9 - Both DIS and HLA
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40. Network Monitoring – VComm Monitor
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41. Instrumentation – Perfmon.exe
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42. Instrumentation (Perfmon.exe)
Performance Monitors
Incoming PDUs
Outgoing PDUs
Dropped TX packets
Incoming transmitter PDUs
Incoming signal PDUs
Incoming entity state PDUs
Incoming ICS control PDUs
Incoming ICS signal PDUs
Number of radios in exercise
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43. Inside VComm
(Section 3)
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44. Signal Processing Models
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45. Path Loss Model Path Loss is Several Models
Free Space Propagation Loss
WGS84 earth model LOS
Refraction
Terrain surface type
Fresnel effects
Multi-path signal fading
Terrain database
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46. Propagation Loss Model
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47. Smooth Earth Model Line-Of-Sight WGS84 Earth Model LOS
Diffraction Effects
Terrain
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48. Fresnel Effects Model Fresnel Zone 1
Up to 60 dBm before LOS interference
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49. Tuner Model
Definition (Bandwidth)
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50. Tuner Model Continued VComm Tuner Model Uses Gaussian functions
Band pass response if Specific to radio
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51. Noise Model Radio Noise Thermal Noise (KTB Noise) Atmospheric Noise
Function of bandwidth
-131 dBm at 25,000 Hz
Atmospheric Noise
Based on several types of noise
Includes galactic and man-made
Zero below 100,000 Hz (ICS frequencies)
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52. Noise Model Continued
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53. Audio Filtering Audio Filtering for Realism
Real radios band pass the audio
300 to 3,000 Hz
Sounds distinctly like a radio
VComm Radio Audio Emulation Filter (object 2055) provides this capability
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54. 300Hz to 3000Hz Band-Pass Filter
Unfiltered DIS Radio
(All Competitors)
Filtered DIS Radio
(Realistic Model)
Click on icons to hear the difference
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55. Other Special Audible Effects
Squelch Tail”
Heard at end of incoming transmission
Function of AGC, s/n level, etc.
Radio Power On and Power Off Sounds
Radio specific
Secure Effects
System Specific Effects
Test tones, etc.
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56. Important Issues to Remember (Section 4)
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57. Coordinate Systems Geodetic Geocentric (DIS) LAT, LONG, ALT X,Y,Z
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58. Coordinate Systems Continued
DIS uses Geocentric
Object to convert Geodetic to Geocentric
Note that 0,0,0 Geocentric is the center of the earth and a de-facto DIS standard for non-propagation loss radio
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59. New Style (V8.0) VComm Radios
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60. Old Style VComm Radios
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61. Device Versus Channel Be Careful When Dealing with Legacy Radios
Devices are two channels of left and right
Channels are independent streams
Device Channel
1 Left 1
1 Right 2
2 Left 3
2 Right 4
Etc…
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62. Antenna Location De-facto Standard
x,y,z = 0,0,0 means no propagation loss and is most widely used
Any other location, and propagation loss model is in effect
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63. Questions and Answers
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64. Any Questions?
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