Mobile DTV Deployment at Fox Television Stations

Mobile DTV Deployment
at Fox Television Stations
“Lessons Learned”
15 Stations
High-VHF and UHF
RF Channels 7-44
Why Mobile DTV?
• US DTV (A/53) developed in 1993
• DTV had to fit 19.39 Mbps into 6 MHz
• Planning factors: Antenna 30 feet high,
with 6-10 dB gain
• DTV training sequences appropriate
for stationary multipath – not moving
• No concept of mobile reception on a
handheld device or with a small
antenna on the ground or in motion
Photo Credit: Richard Elzey
Mobile DTV: ATSC A/153
• Mobile data in MPEG-TS packets with an unreferenced PID
– Typically 0x1FF6
– Ignored by legacy receivers
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Formatted as IP packets (encapsulated in TS)
H.264 video – HE AAC audio – in RTP / multicast UDP
Encryption possible
More coding for smaller antennas
– About 4:1 additional coding over legacy
• Transmitted in specific time slots
– Receivers save power turning on only during slots required for service
• Additional training sequences
– For mobile reception up to ~200 MPH
Mobile IP Multicast signals
Mobile Bandwidth Use - NoG
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16 time slots, 12.1ms each
NoG = Number of Groups of mobile data (to fit into slots)
1 NoG “costs” 917 kbps of legacy signal, and
1 NoG provides ~240 kbps of Mobile payload (HQQQ coding)
NoG=1: 416x240 H.264 baseline profile - Kids animated shows
NoG=2: 416x240 H.264 baseline profile - Live video
NoG=3: 640x368 H.264 main profile - Great live video
Cadence of
Mobile Data
PIDs in TS
Mobile PIDs
(lime)
FTS Mobile Block Diagram
FTS Larcan Mobile Equipment
H.264 Encoder
Mobile Exciter
Mobile Mux
GPS Receiver
ESG
Ethernet Switch
If you Standardize it, will they come?
• ATSC publishes A/153 in 2009
…2010…
…2011…
• Only a handful of stations on the air
• Almost no shipping consumer products
– CE’s: “Where are the stations?”
– Stations: “Where are the CE devices?”
MCV Creates the Mobile Ecosystem
Solves “chicken and egg problem” to commercial deployment of mobile TV
● Legal framework for affiliate mobile
content
● Most major networks participating
Content
● FOX & NBC O&Os, ION
● 9 other major station groups
Devices
Spectrum
● Upgraded 80+ stations, 35
markets, >55% TVHH
● Launched Dyle Mobile TV
brand
● Dyle creates uniform quality
level & CA system
● Worked with partners to
launch initial devices
Infrastructure &
Technology
● Dyle™ Mobile TV application
● CAS deployment & viewership data
● Signal monitoring
Dyle App
• Free-to-the consumer; requires initial registration – anonymized demographics
• Android and iOS Version
• Decrypts MCV stations & plays other “in the clear” stations
• Station list pre-populated based on location (full OTA scan available as well)
• Developed by MobiTV
Dyle App Screenshots
Displays ESG:
Channel Icon Bar
“Stoplight” RF signal indicator
FOX Lab Dyle RF Testing
1. Sensitivity (how much EM field
required for TOV)
2. Multipath/Echo Rejection
3. Co-channel Interference Rejection
4. Adjacent & Other Undesired Channel
Interference Rejection
Mobile OTA Monitoring
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Monitor RF & MPEG TS
Monitor A/53 & A/153 PSI
Monitor Mobile IP stream validity
Show available services & ESG
Monitor Mobile Video and decoded Closed Captions
A/53: What Comes out Can go Back In
• A/53 TS recorded to disk is same TS that left the
MUX
A/153: What Comes out Can’t go Back In
• Mobile packets have non-systematic RS encoding in the exciter
that A/53 receivers can’t decode
• Requires a pro A/153 receiver – doesn’t exist
• Recordings must be made right out of the Mux, not over the air
Mobile DTV Synchronization
• Mobile data needs to be in the right place at
the right time
• Mobile Mux and Mobile Exciter must be
synchronized
– Typically by GPS
• Thus no add/drop any TS packets between the
mux and transmitter – even nulls
ASI to 310 problems
• ASI – asynchronous serial interface, does not
run precisely at ATSC data date
• SMPTE 310 interface data rate 19,392,658 bps
+/- 54
• ASI to 310 interfaces typically add/drop null TS
packets to achieve 310 data rate
• This blows up Mobile DTV!
Problems when No One is
Watching….
• No one notices that draft standard was
implemented instead of published one
• Mobile signal goes off the air and no one
notices
• Lip Sync?
• Loudness?
– No dialnorm metadata in AAC anyway
iOS Preferred Loudness
• Five audio clips of network
material
• ­20 LKFS and ­14 LKFS
• Listeners in office environmen
ts
• Mix of iPhones, iPads,
headphones, speakers, earbuds
• Listeners preferred average:
– 9.5/16 volume for ­20 LKFS
– 8.2/16 volume for ­14 LKFS
• ATSC moving to -14 LKFS for
mobile
Shipping Dyle Consumer Devices
• Samsung Galaxy Lightray
4G phone (MetroPCS)
• Elgato EyeTV Mobile
– iOS 30-pin
• ESCORT
– iOS 30-pin
Announced Consumer Devices…
RCA
Android
Tablet
Belkin
iOS 30-pin
Audiovox
In-Car Solution
And premiering in the HPA 2013
Demo Room…
• Elgato EyeTV Micro ATSC M/H Receiver for
Android
Join us on the Air with Mobile!
~116 MDTV Stations on the air today
Special thanks…
• United Service Source, Inc.
• Jim DeFilippis
• Yves Montane, Satoshi Suga, Denise
Schnelle
• Robert Murch, Tim Redmond
• Earl Arbuckle