Comparing ranges at different frequencies and dBm
时间:04-05
整理:3721RD
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Texas Instrument has a zigbee 2400 MHz chip CC2530 with up to 4.5 dBm (2.8 mW), and an NFC 13 MHz chip TRF7970A with up to 23 dBm (200 mW). Does this mean that the NFC has longer distance range than the zigbee, because it transmitts with 70 times more power? Or does lower frequency require higher effect for the same range?
It would be odd to have NFC with longer range than zigbee, when considering common applications.
It would be odd to have NFC with longer range than zigbee, when considering common applications.
NFC isn't radio communication. It uses inductive couplers rather than matched antennas, it transmits only a negligible part of the output power as electromagnetic wave to free space (μW or below).