Smart home gateway system over Bluetooth low energy with wireless energy transfer capability

EURASIP Journal on Wireless Communications and Networking

Table 2 Expected efficiency of practical WETI operation

	Frequency band
	5725–5875 MHz	2400–2483.5 MHz	869.4–869.65 MHz	433.05–434.79 MHz	138.2–138.45 MHz	40.66–40.79 MHz	26.85–27.255 MHz
Maximum duty cycle, % ^a,b	100	100	10	100	10	100	100
Maximum power, mW ^a	25 EIRP	10 EIRP	500 ERP	10 ERP	500 ERP	500 ERP	500 ERP
Antenna length, cm	2.6	6.1	17.2	34.5	108.5	368.6	555.6
Maximum distance between gateway and sensor for WETI, m ^c	0.8	1.2	31.8	9	200	680	1025
Amount of power transfered into energy and buffered, mW ^c,d	0	0	0.02	0.0017	0.86	10	22.7
Harvesting time for enabling transmission of one BLE packet, s ^c,d,e	infinity	infinity	1.8	22	0.05	0.004	0.002
Portion of energy for powering active BLE transceiver replenished by WETI, % ^c,d,f	0	0	0.03	0.003	1.4	16.4	37.2

^aAccording to [36]
^bRelative to 1 hour, see [36]
^cAssumed that the transmitter is using the maximum possible transmit power
^dDistance between the gateway and the sensor is 5 m
^eRefer to Table 4 in [6]; for the TI CC2540 BLE transceiver, the energy required for sending an ADV_NONCONN_IND packet is 39 μJ
^fPower consumption for active mode was assumed to equal 61.1 mW; this is the average power consumed by TI CC2540 BLE transceiver while sending maximum-size frames (see Table four in [6]). The consumption for receiving acknowledgments is included