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Wireless Communication Basics

Which is a characteristic of LPWA (low-power wide-area) wireless communication used in IoT?

  1. AThe transmission rate is low, but it covers a wide area of several kilometers or more with little power consumption
  2. BThe transmission rate is high, making it suitable for sending high-definition video in real time
  3. CThe communication range is a few centimeters, and it is used by holding a card or smartphone over a reader
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Answer: A. The transmission rate is low, but it covers a wide area of several kilometers or more with little power consumption

LPWA is a general term for wireless communication intended to send small amounts of data, such as sensor readings, over long distances from devices that run on batteries for years. Keeping the transmission rate low allows even weak signals to be received, extending the range. Some, such as LoRaWAN, use license-exempt bands (such as the 920 MHz band in Japan), while others, such as LTE-M and NB-IoT, use mobile phone bands.

  • A. Correct. Keeping the rate low achieves both low power consumption and long range.
  • B. LPWA transmission rates are generally low and unsuitable for video.
  • C. These are characteristics of short-range wireless such as NFC.
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