FM Synchronous Boosters
And Single Frequency Networks
Tim Bealor, VP RF Products
John Macdonald, Sales Manager, Europe
Middle East, Africa
Lutfi Aysan, Onair Medya
Today’s Topics
• Company Overview• Sample Installations & Technological Issues• System Configurations• BE Solutions
Today’s Topics
• Company Overview• Sample Installations & Technological Issues• System Configurations• BE Solutions
Corporate Overview
Nearing fifty years of serving radio broadcasters worldwide
Headquartered in Quincy, Illinois
Products encompass program generation, audio and data management, inter-facility transport and analog and digital transmission
FM Transmitters
• Comprehensive product line from 50W to 70KW• All transmitters upgradeable to HD Radio
AM Transmitters
• Comprehensive product line from 500W to 100KW• All transmitters upgradeable to digital
Transport Products
Marti• The ONLY answer for traditional RPU
applications• Reliable, cost effective composite &
discreet STL’s
Digital Cellcast• Take your station anywhere!• The ultimate in remote portability
Audio Over IP• No more worries about long,
unreliable paths• Originate your signal with remote IP
access from your laptop
Big Pipe LT• High bandwidth digital performance• Upgrade you link for HD
compatibility at an affordable price
Studio Products
AudioVAULT• Broadcast delivery software system• Tools to manage, create and deliver
content• Personalized workspaces
The Radio Experience (TRE)• Complete message management
capabilities• Supports RDS, RT+, HD, Web
and more
SoniXtream•Turnkey internet streaming services•Branded custom players•Ad insertion •Multiple revenue generation
components
Today’s Topics
• Company Overview• Sample Installations & Technological Issues• System Configurations• BE Solutions
Synchronous FM Boosters:Why do we need them?
Scenario #1 – Filling in dead spots in coverage.– Allows the broadcaster to fix areas that are terrain shielded but would otherwise
be within the 1 mV/M (or other) contour.
Scenario #2 – Covering a long road with one station.– Increasingly, stations are getting licenses for a coverage along a major highway
with just a single frequency.
Scenario #3 – Regional coverage.– Allows a licensee to cover a region with several stations – all on the same
frequency
Fixing Dead Spots
Dead spots are created by terrain shielding – where there is no reasonable line of site.A low power, on frequency booster may be located within the shadowed area to improve coverage.
Main TransmitterInterference Areas
Booster Transmitter
Main 25kW FM Transmitter
Tall Buildings – Central Business
DistrictTerrain Shielded Area
Synchronous FM 250W Booster
Fixing Dead Spots
Creating continuous coverage on a road
Long, important highways are good targets for a radio station you can listen to without changing the dial.
Many small transmitters are synchronized to provide unbroken service.
Regional Coverage
True, regional stations may be created by synchronizing high power stations.
Station identity can be created – the frequency is the same across the whole region.
Frequency allocation is easier – the same frequency can be used for adjacent stations.
The Problem: Interference Zones
Where the coverage areas overlap, and the ratios of the signal strengths approach unity, the signal quality is affected.
Basel
Zurich
Interference Zone
Key Issues
•Where the coverage areas overlap, and the ratios of the signal strengths approach unity, the signal quality is affected. •If the RF carriers are not frequency synchronized, significant distortion and noise will result.•If the audio levels are not exactly the same, the noise floor increases dramatically with a “white noise” which varies with the level of the audio.•If the pilots are not synchronized, in both frequency and phase, the pilot detector in the receiver will switch back and forth and this will be audible in the stereo signal.•If the audio phase is not synchronized, distortion results.•If everything – audio, pilot & carrier are all synchronized, the signal will be optimized.
Composite Baseband: L=5kHz, R=7kHz
0 Hz 10 kHz 20 kHz 30 kHz 40 kHz 50 kHz
0dB
-20dB
-40dB
-60dB
-80dB
-100dB
Two carriers – in phase
0 Hz 10 kHz 20 kHz 30 kHz 40 kHz 50 kHz
0dB
-20dB
-40dB
-60dB
-80dB
-100dB
Two carriers – ¼ dB deviation difference
0 Hz 10 kHz 20 kHz 30 kHz 40 kHz 50 kHz
0dB
-20dB
-40dB
-60dB
-80dB
-100dB
Two carriers – ½ dB deviation difference
0 Hz 10 kHz 20 kHz 30 kHz 40 kHz 50 kHz
0dB
-20dB
-40dB
-60dB
-80dB
-100dB
Two carriers – 1 dB deviation difference
0 Hz 10 kHz 20 kHz 30 kHz 40 kHz 50 kHz
0dB
-20dB
-40dB
-60dB
-80dB
-100dB
Two carriers – 90° time delay
0 Hz 10 kHz 20 kHz 30 kHz 40 kHz 50 kHz
0dB
-20dB
-40dB
-60dB
-80dB
-100dB
Two carriers – 180° time delay
0 Hz 10 kHz 20 kHz 30 kHz 40 kHz 50 kHz
0dB
-20dB
-40dB
-60dB
-80dB
-100dB
Today’s Topics
• Company Overview• Sample Installations & Technological Issues• System Configurations• BE Solutions
Previous System Block Diagram
May be accomplished with GPS receivers at both sites, or by use of a reference tone to sync both exciters.
Problem: Doesn’t provide synchronized audio phase or level, or pilot phase.
What’s needed
(2) FXi-60 or FXi-250 Digital FM exciters
(1) Uncompressed Digital STL with AES/EBU input and output. We have used the Moseley Starlink 9400Q.
(2) Rack mounted GPS receivers with 10MHz TTL level output and outdoor antenna. We have used the ESE Model 110.
(1) AES/EBU Splitter/Delay with minimum delay time of approximately one microsecond, and increments of one microsecond to a maximum delay of one millisecond. We have used the Quantec Zombie 1212/DSP.
Other Company System Block Diagram
UncompressedAES/EBU STL
UncompressedAES/EBU STL
Fxi-60/250Digital Exciter
Fxi-60/250Digital Exciter
GPS Receiver with 10MHzTTL Level Output
AES/EBU Delay / Splitter
RF ToTransmitter
RF ToTransmitter
GPS Receiver with 10MHzTTL Level Output
Transmission Site A Transmission Site B
AES/EBUAudio from
Studio or STL
STL Path
BE System Block DiagramUsing FXi ESP
UncompressedAES/EBU STL
UncompressedAES/EBU STL
Fxi-60/250Digital Exciter
Fxi-60/250Digital Exciter
GPS Receiver with 10MHzTTL Level Output
AES/EBU Delay / Splitter
RF ToTransmitter
RF ToTransmitter
GPS Receiver with 10MHzTTL Level Output
Transmission Site A Transmission Site B
AES/EBUAudio from
Studio or STL
STL Path
Today’s Topics
• Company Overview• Sample Installations & Technological Issues• System Configurations• BE Solutions
BE’s approach - Synchronize everything
•The entire system is digital. •The audio is synchronized by using an uncompressed Digital AES/EBU Link• The levels of the transmitted audio are locked because we use the AES/EBU inputs on the FXi ESP series exciter.•The carriers and the pilot are synchronized by using the internal GPS receiver. •The delays are extremely accurate because of 1usec internal delay accuracy•A patent has been applied for.
This is what makes it happen
FXi 60/250esp• Adaptive pre-correction• Internal delay• Internal GPS receiver• IP connectivity • Dual RF outputs• Direct to carrier synthesis
And Much Much More
No External GPS Required
• Internal GPS Receiver with rear panel antenna connection• Self Contained Synchronous Booster Operation
— Locked to GPS, 10MHz and 1PPS
— Pilot and Carrier locked to 1PPS
• 1usec delay resolution designed to specifically accommodate booster operation
Timing Inputs
Ideal for Analog and HD Simulcast
• Only BE provides delay of composite input• Delay AES Inputs• 1usec delay resolution• 0 to 15 seconds delay of FM Analog for Diversity Delay• User defined Ramp Up and Ramp Down Time
0.1dB Deviation Accuracy
• If the modulation levels from two different exciters in a booster application are not exactly the same, it will result in the audio having a significant amount of noise and distortion.
• When implementing a synchronous or single frequency network the AES audio input should be used.
• This allows the FXi esp exciter to set the modulation levels to 0.1dB accuracy.
• Level differences of 0.3 to 0.5dB can result in poor audio quality near the overlap areas.
System Synchronization
• Signal Outputs for external use— 10MHz
— 1PPS
— 19kHz Pilot
• Internal GPS eliminates need for additional GPS receiver
Timing Outputs
True Dual Exciter Operation
• Dual RF Outputs allow one exciter to drive TWO transmitters!
• High Power (0 to 250 watts)• Medium Power (0 to 15 watts)• Higher output power levels eliminate the need for
additional external amplifiers
High Power RF Output
Medium Power RF Output
• More than any competing brand!
• Audio Inputs— Dual Independent AES/EBU Inputs eliminate the need for
external AES switching
— L & R Analog Inputs
— Balanced & Unbalanced Composite Inputs
Rich in Audio Inputs…
Dual Independent AES Inputs
L&R Analog Inputs
Balanced & Unbalanced Composite Inputs
..with Easy Source Setup
• Primary/Backup Audio Source Setup— AES 1— AES 2— Composite— Analog L&R
AUDIO SETUP MENUBACK
DCOMPOSITESETUPD
COMPOSITESETUP
COMPOSITE OUT SETUP
ANALOG L/R SETUP
PRI/BACKUPAUDIO SETUP
INT SCA SETUP
EXT SCA SETUP
INT RDS/RBDS SETUP
EXT RDS/RBDS SETUP
STEREO/MONO SETUP
AES SETUPACTIVE AUDIO SOURCE
ACTIVE AUDIO SOURCE
SAMPLE RATE
HELP
COMPOSITE
PRIMARY AUDIO SOURCE COMPOSITE
BACKUP AUDIO SOURCE AES
AUDIO INPUT SELECTIONS
44.1 kHz
• Truly expands your RDS message capabilities! —Accepts dynamic serial RDS data or external generator—Eliminates need for external RDS generator—Serial data from source
Dynamic RDS Generator
External RDS Generator Input
Dynamic RDS Input
Flexible I/O Configuration
• Allows flexible operational control for specialized installations• More than 45 unique settings• User-Defined General Purpose I/O
— Can be used with any remote interface— 12 inputs with 12 outputs
• All I/O’s are mode selectable
Defined GPI/O
User-Defined GPI/O
“True” Silence Sense Detection
• No dead air in your revenue stream• User adjustable parameters-You’re in Control!
— Threshold Level
— Switchover Time
— Switchback TimeMAIN
DCOMPOSITESETUPD
SIL SENSEON/OFF
PRI THRHD SET
BCKUP THRHD SET
SWITCHOVERTIME SET
SWITCHBACKTIME SET
BACK
PRIMARY DELAY SELECTIONS
SILENCE SENSE SETUP MENU
SILENCE SENSE SETUP
SILENCE SENSE STATUS SWITCHOVER TIME
SWITCHBACKTIMEPRIMARY THRESHOLD
BACKUP THRESHOLD
HELP
ENABLED
20%
20%
10 Sec
10 Sec
Upgrades Station Measurement Capability
• Instrument Grade Spectrum Analyzer eliminates the need for an external unit
• Capable of measuring NRSC mask compliance• High resolution spectrum display of all modes
— -20 dB ratio FM+HD— -10 dB ratio FM+HD— FM Only— HD Only
Ethernet Connectivity
• IP Addressability for Remote Access• Easy set up
MAIN
DCOMPOSITESETUPD
MODULE SELECTION
IP SETUP
SUBNET SETUP
XMTRT-SERIESGATEWAY
SETUP
UNI/BIDIRECTIONAL
BACK
IP SETUP MENU
REMOTE INTERFACE IP MODULE
IP ADDRESS
SUBNET
GATEWAY
EXGINE MODULE
IP ADDRESS
SUBNET
GATEWAY
HELP
10.2.4.105
255.255.255.255
10.2.2.21
10.2.4.105
255.255.255.255
10.2.2.21
EXPORTER MODULE
IP ADDRESS
SUBNET
GATEWAY10.2.4.105
255.255.255.255
10.2.2.21
LINK TYPE UNI-DIRECTIONAL
MAC ADDRESS 00-03-F4-02-0E-02
Reduced Downtime in Backup Operation
• 8 Independent, selectable and downloadable configurations— Mode of Operation
— Frequency
— Output Power
— Audio Source
• N+1 Applications• Backup Transmitter Applications
Reduces AES Conversion Cost
• Provides Composite output to drive main analog or backup transmitter
• Eliminates the need to upgrade an analog only transmitter to accept AES input
• Eliminates need for external stereo generator
Composite Output
Efficient Operation and Troubleshooting
• Front Panel Diagnostics and Metering— Larger Front Panel Display
• 8.4” display— Soft-Key Menu Selection— 18 analog parameters
• Forward Power• Reflected Power• Power Supply Voltages
— Alarm Indication• Latched Output
— Fault Indication• Non Latched
— Event Logging
Lower Cost of Ownership
Spectrum Analyzer
GPS Receiver
External Power Amplifiers
AES External Switching
External Stereo Generator
Standby Exciter
Backup Transmitter
$ 6,000- $20,000
Things you may NOT need with the FXi 60/250esp….
$ 1,300$ 3,500
$ 800
$ 2,000
$ 5,000- $15,000$ 15,000
QUESTIONS?
Thank You
Tim Bealor, [email protected]
John Macdonald, [email protected] www.bdcast.com
Lutfi Aysan, [email protected]
System Timing
ABC
D
A= Transmitter Site AB= Transmitter Site BC= Interference ZoneD= Studio
AB= 20 kmAC= 17 kmBC= 3 kmDA= 7 kmDB= 24 km
AB+BC-AC = km of differential delay20+3-17=66 x 3.34= 20 micro seconds of delay