Design and Analysis of a Compact Superwideband Millimeter Wave Textile Antenna for Body Area Network

Table 5

Free space comparison between different substrates.

Substrate	Relative permittivity	Thickness (mm)	Return loss magnitude (dB)	Gain (dBi)	Radiation efficiency (%)
100% polyester	1.9	1.5	-11.25	5.70	89.06
Jeans	1.7	1	-11.16	5.34	90.38
Denim	1.88	1.5	-11.20	5.83	89.04
Silk	1.75	1.16	-10.61	5.68	89.36
Tween	1.69	1.37	-11.38	6.32	88.71
Panama	2.12	1.04	-09.92	6.27	88.88
Felt	1.38	1.38	-13.15	6.76	91.69
Moleskin	1.45	1.17	-13.08	5.88	91.33
Cotton	1.63	1.5	-11.97	6.99	88.96
Quartzel fabric	1.95	1.5	-11.36	5.66	89.42
Cordura/lycra	1.5	0.5	-14.10	5.91	93.95