Broadband Wireless Communication System for Public Safety

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Broadband Wireless Communication Systemfor
Public Safety
Global Standards Collaboration (GSC) 14

• Homare Murakami, Masayuki Oodo, Hiroshi Harada
• NICT / ARIB

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In Japan, digitalization of terrestrial TV
broadcasting service to be completedin July,
2011 gt reduce the total bandwidth for
terrestrial TV broadcasting
Background frequency band
current analog TV broadcasting (total 370 MHz)
90 108 170 222 470

770 MHz
current
1.mobile multimedia broadcasting
after July, 2011
90 108 170 205 222 470
710 720 730
770MHz
3.ITS
4.cellular system
terrestrial digital TV broadcasting (240 MHz)
gt 130 MHz newly available
2. Broadband mobile communications for public
safety
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current system
Strategic Direction current and expected
systems for public safety
-- narrow band voice low data rate
transmission -- difficulty in interoperability
expected system
-- shared by multiple public organizations --
broadband access service (several Mbps) for
mobile users (main application moving
pictures transmission) -- highly-efficient
spectrum use gt OFDM-based system
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Challenges for reliability(1/2) Radio
Propagation Field Tests
delay spread gt 10usec
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Challenges for reliability (2/2) Transmission
Experiments
In order to investigate adequate OFDM parameters,
following combinations were tested.
IEEE 802.22 Profile A
GSM Typical Urban
For long-delayed ( 20µsec) channel
environment, Mode2 (narrower subcarrier interval,
resulted in good transmission performance.
For short-delayed ( 5µsec) channel environment,
no large differences among all modes were seen.
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Next Steps/Actions

• Toward the realization of broadband wireless
  communication system for public safety using the
  VHF bands (a portion of vacant lots after
  retirement of analog TV broadcasting service),
• R D of the system have been progressed.
• Indoor and Field experiments have been conducted
• to decide the system parameters (service
  coverage, PHY parameters etc.).