Wi-Fi backscatter communication has lower power consumption and lower cost than active Wi-Fi. However, most of the current researches have the problems of large power consumption of field programmable gate array (FPGA) and high manufacturing cost of application specific integrated circuit (IC). Therefore, a passive Wi-Fi backscatter communication method based on microcontroller (MCU) is proposed. The low-frequency MCU is used to generate the Wi-Fi backscatter modulation waveform with nanosecond timing accuracy. After the low power design and optimization, the MCU power management based on energy harvesting and passive system design are carried out. And the passive Wi-Fi prototype is demonstrated for the first time. Tests show that the instantaneous power consumption of communication is 1.8mW, which is 2~3 orders of magnitude lower than that of active Wi-Fi. The system has a standby power consumption of 2.5μW and an effective communication distance of 15 meters. It is compatible with existing commercial Wi-Fi devices and has low cost and no battery.
Key words
passive Wi-Fi /
backscatter /
Internet of Things (IoT) /
low power consumption
{{custom_keyword}} /
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
References
[1] Ahmed N,Rahman H,Hussain M I.A comparison of 802.11ah and 802.15.4 for IoT[J].ICT Express,2016,2(3):100-102.
[2] Want R.An introduction to RFID technology[J].IEEE Pervasive Computing,2006,5(1):25-33.
[3] Bharadia D,Joshi K R,Kotaru M,et al.BackFi:High throughput WiFi backscatter[A].ACM Conference on SIGCOMM[C].ACM,2015.283-296.
[4] Kellogg B,Parks A,Gollakota S,et al.Wi-fi backscatter:internet connectivity for RF-powered devices[A].ACM Conference on SIGCOMM[C].ACM,2015.607-618.
[5] Katti S,et al.HitchHike:Practical backscatter using commodity WiFi[A].ACM Conference on Embedded Network Sensor Systems[C].ACM,2016.259-271.
[6] Gang Y,Liang Y C,Rui Z,et al.Modulation in the air:Backscatter communication over ambient OFDM carrier[J].IEEE Transactions on Communications,2017,PP(99):1-1.
[7] Yang G,Zhang Q,Liang Y C.Cooperative ambient backscatter communications for green Internet-of-Things[J].IEEE Internet of Things Journal,2018,5(2):1116-1130.
[8] Kellogg B,Talla V,Smith J R,et al.PASSIVE WI-FI:Bringing low power to Wi-Fi transmissions[J].Getmobile Mobile Computing & Communications,2017,20(3):38-41.
[9] IEEE Std 802.11TM-2012(Revision of IEEE Std 802.11-2007) Part 11:Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications[S].New York:IEEE Computer Society,2012.
[10] Chabalko M J,Shahmohammadi M,Sample A P.Quasistatic cavity resonance for ubiquitous wireless power transfer[J].Plos One,2017,12(2):e0169045.
{{custom_fnGroup.title_en}}
Footnotes
{{custom_fn.content}}
Funding
2018 Major Program of Innovation Project of Hubei Province (No.2018AAA064); 2018 Experimental Technology Research Project of China University of Geosciences (Wuhan) (No.SJ-201831)
{{custom_fund}}
PDF(1753 KB)
