Mapping of FM and HD Radio Coverage
description
Transcript of Mapping of FM and HD Radio Coverage
Mapping of FM
and HD Radio Coverage
Brian Casey, Leandro Franca, and Thomas Shanks
April 22, 2009
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Project SummaryProject Summary
• Measure radio station coverage through:
– RF Field Strength (conventional method)
– Signal-to-Noise Ratio of audio (what listeners actually hear)
• Provide maps of data
• Determine statistical information of SNR
• Compare results with and without HD
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Block Diagram of SystemBlock Diagram of System
•BLUE 75Ω coax w/ F connector•RED 50Ω coax w/ UHF connector•GREEN Data connector•BLACK Audio cable RCA to 1/8”
Antenna
BPF88-108MHz
25dB AmpNF~5.6
SpectrumAnalyzer
HD RadioHD Radio
Analog FM Radio #1
Analog FM Radio #2
Audio Input (PC)
ComputerAnalyzingSoftware
GPS
DIOS
plitt
er
Magnetic MountWhip
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Car and hardware photosCar and hardware photos
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Software DesignSoftware Design
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Transmission of Test TonesTransmission of Test Tones
1 kHz250 ms
1 kHz250 ms
Silence250 ms
Silence250 ms
• 100% modulation, stereo on, other sub-carriers and processing off
• Enable/Disable HD
• Interrupts programming, so time of tests 1:30 - 6:00 am
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Cost AnalysisCost Analysis
Item Planned Final Our
Rohde & Schwarz FSH3 Spectrum Analyzer
8,200 8,200 -
Consumer HD Radio 150 99 - Laptop 800 800 - NI LabVIEW Professional 4,299 4,299 - BR-355 GPS 43 43 - Labor ($35/hr per person) 8,400 10,500 - USB to PS/2 adapter 10 30 10 Amplifier 4-way Splitter 20 20 20 Misc. components 320 385 185 Audio Card - 90 90 Car maintenance 60 60 60 Gas/200 miles 40 40 40 NI Sound and Vibration - 3,999 - RF BPF - 250 - Magnet Mount and Antenna 77 77 77
Total (in USD) 22,429 28,892 482
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Changes since PDRChanges since PDR
PDR Now
Matlab gnuplot
Rapid switching on/off of HD Separate runs
3 radios 2 radios
Sony radio as reference Sony DSP not good for reference
Drive whole metro area Drive northern third of area
Simultaneous SNR of radios Alternate SNR capture of radios
DIO for HD on/off detection Button in LabView for HD on/off
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RF Power vs. Distance From TransmitterRF Power vs. Distance From Transmitter
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RF Power MapRF Power Map
(dB
m)
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SNR MapSNR Map
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Driving PathDriving Path
Full path Validation Path
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DemonstrationDemonstration
• Show working automated system (test drive)
• Describe functionality of sub systems• Provide data plots and distribution information
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Remaining WorkRemaining Work
• Post-processing software to create maps
• Implementation of NI Sound and Vibration Toolkit for SNR and ITU-468 Filter
• Calibrate and Validate SNR
• Drive Path
• Compare with and without HD
• Plot final data
• Prepare documentation and post everything on site
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Future WorkFuture Work
• Full coverage drive
• Calibrated antenna to determine field strength from dBm measurements
• Use truly representative radios
• Analyze time and environmental variances of signal
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Questions?