Table 2.

Quantitative comparison between some of the state-of-the art microwave glucose sensors and the present design.

References	Microwave structure	Main frequency (GHz)	Sensitivity (converted to KHz/1 mM/l)	Distance between sample and the sensor (mm)	Sample liquid	Sample volume (µl)	Lowest glucose concentration measured (mM/l)	Comments
41	Discrete double split-ring Resonators	1.5	3.2	1	DI water	21,000	25	High power consumption Non-wearable and not flexible Readout circuitry should be attached to the sensor Low sensitivity
54	ENG-based microwave filter device	2	252	0.1	DI water	2	111	High power consumption Non-wearable and not flexible Readout circuitry should be attached to the sensor High sensitivity due to very small distance between the sample and the sensor
55	Microstrip Antenna Driven Ring Resonator	2	16	0.0014	DI water	90	555	Enzyme based Not flexible Readout circuitry should be attached to the sensor Medium sensitivity Saturable sensor
56	Split ring resonator	1.5	468	0.1	DI Water	NA	55.5	Non-wearable and not flexible Readout circuitry should be attached to the sensor High sensitivity due to very small distance between the sample and the sensor
This work	Chipless tag split ring resonator	4	38	1.4	Mimicked ISF	200	5	Ideal for wearable sensors Zero power consumption for the tag sensor Distant communication capability High sensitivity