November 13, 2017

Physical limits on directional beam performance of 28 GHz links

  • Chizhik D.
  • Valenzuela R.
  • Venkatesan S.

Impact of finite coherence in frequency and time on directional beam in a canonical 28 GHz small cell link is assessed. Terminal motion and delay spread are found to limit the maximum achievable directional gain due to the need to measure the channel across time and frequency. It is found that pedestrian speeds (1m/s) still allow 1 Gbps rate at 100 m in Non-Line-of-Sight (25 dB shadow) link using 32 array elements in 300 MHz bandwidth, nearly 10x the rate of a 10 MHz-wide cellular link at 2 GHz. Vehicular speed of 30 m/s requires nearly 2x the element count to reach the same rate.

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© 2017 International World Wide Web Conference Committee (IW3C2), published under Creative Commons CC BY 4.0 License. Many of today's websites have recognised the importance of mobile friendly pages to keep users engaged and to provide a satisfying user experience. However, next to the experience provided by the sites themselves, ...

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© 2017 International World Wide Web Conference Committee (IW3C2), published under Creative Commons CC BY 4.0 License. Uber is a popular ride-sharing application that matches people who need a ride (or riders) with drivers who are willing to provide it using their personal vehicles. Despite its growing popularity, there exist ...

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© 2017 International World Wide Web Conference Committee (IW3C2), published under Creative Commons CC BY 4.0 License. Recent studies in social media spam and automation provide anecdotal argumentation of the rise of a new generation of spambots, so-called social spambots. Here, for the first time, we extensively study this novel ...