WiB - ultra wideband efficient UHF broadcast

[[Teracom]], inspired by earlier research{{cite journal|author1=Yiyan Wu|author2=Bo Rong|author3=Khalil Salehian|author4=Gilles Gagnon|title=Cloud Transmission: A New Spectrum-Reuse Friendly Digital Terrestrial Broadcasting Transmission System|journal=IEEE Transactions on Broadcasting|date=21 June 2012|volume=58, Issue: 3|pages=329 - 337|doi=10.1109/TBC.2012.2199598|url=http://ieeexplore.ieee.org/document/6222350/?arnumber=6222350|accessdate=25 June 2017|publisher=IEEE|issn=1557-9611}}, introduced a new system concept dubbed "WiB", that aims to improve [[frequency reuse]] in the [[Ultra high frequency|UHF band]] while at the same time enable savings in both operating power and capital expenditures costs.{{cite conference|author1=E. Stare|author2=J. J. Giménez|author3=P. Klenner|title=WIB – A new system concept for Digital Terrestrial Television (DTT)|conference=IBC 2016|date=16 March 2017|url=https://www.ibc.org/tech-advances/wib--a-new-system-concept-for-digital-terrestrial-television-dtt/895.article|archive-date=16 March 2017|archive-url=https://www.teracom.se/contentassets/a87c55ddc7444f909cf2f184ba778faf/wib-paper---published-ibc-version.pdf|accessdate=25 June 2017|publisher=International Broadcasting Convention|location=Amsterdam}}{{cite journal|author1=E. Stare|author2=J. J. Giménez|author3=P. Klenner|title=Technical Review: WiB – A New System Concept for Digital Terrestrial Television (DTT)|journal=EBU Technology & Innovation|date=6 March 2017|url=https://tech.ebu.ch/docs/techreview/2017-03-06_Technical%20Review_WiB_Stare_etc.pdf|publisher=EBU|accessdate=25 June 2017}}

Simulation results hint at an attainable [[spectral efficiency]] of at least 1.37-1.6bit/s/Hz and a capacity increase in the range of 37-60%, while outlining possibilities for further optimizations.

The concept also hints at possible methods of convergence and coexistence with future [[5G]] mobile communication technologies, although this was not the main focus of the proposal.

==Innovation to broadcast towers==

  • each tower should transmit the whole 224MHz of [[Digital terrestrial television|DTT]] spectrum, eliminating channel combiners
  • a much lower transmission power is used (about 90% less)
  • modulation is more robust (e.g., [[Phase-shift keying#Quadrature phase-shift keying .28QPSK.29|QPSK]])
  • relaxed equipment requirements
  • synchronization similar to [[Single-frequency network|SFN]], but with different content and orthogonal scattered pilots


==Expected enhancements to receivers==

  • frequency hopping (e.g., Time-Frequency Slicing)
  • should be able to tune to wider channels (e.g., 32MHz instead of 8MHz)
  • antenna discrimination considerations
  • layered Successive Interference Cancellation (SIC), performance could be further improved when optimizing for QPSK vs. QPSK.
  • variable bit rate services via multiple [[DVB-T2#Technical details|Physical Layer Pipes]]
  • optional Interference Cancellation via [[Beamforming]]


==References==
{{Reflist}}

==External links==

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