# I-Shaped Metamaterial Using SRR for Multi-Band Wireless Communication
## 6 ISMeTM Unit Cell Analysis  
This section discusses the analysis of the proposed ISMeTM unit cell parameters. The Nicolson-Ross-Weir method has been used to extract the MeTM parameters. Detailed electromagnetic characteristic in terms of permeability, permittivity, relative index and the scattering parameters of the MeTM are shown in Figure 5. The CST Microwave Studio software is used to investigate the performance of the proposed ISMeTM. The analysis validates that the effective magnetic permittivity (\(\varepsilon_{r}\)) is negative, the electric permeability (\(\mu_{r}\)) is positive, and relative refractive index (\(\eta_{r}\)) is positive and negative within the same resonance frequency bands. As a result, these characteristics show that the proposed ISMeTM unit cell shows SNG metamaterial properties. The structure is designed to produce multi-band operation. Due to the compact nature of the ISMeTM, it can be utilized in antenna design for improving antenna performance. The proposed ISMeTM can also be used in satellite communications, WiFi devices, weather radar systems, surveillance etc.  
The S-parameters and the effective parameters of the proposed ISMeTM unit cell are presented in Figure 5a,b, respectively. The obtained simulated S\({}_{21}\) parameter of ISMeTM shows the resonance frequencies at 6.31, 7.79, 9.98, 10.82, 11.86, 13.36 and at 15.5 GHz in the C/X/Ku-bands.  
Simulation of a time-dependent electromagnetic (EM) wave is the effective parameter utilized to measure the response of the MeTM cell design. Modifications in the geometric shape of the design can affect the permittivity and permeability characteristics. The real and imaginary values of the effective permittivity, effective permeability, and effective refractive index are shown in Figure 5b. From Figure 5a, it can be observed that the S21 shows the dips at 6.31, 7.79, 9.98, 10.82, 11.86, 13.36 and at 15.5 GHz. The 3-dB bands can be observed from the Figure 5a as 3.99-6.77 GHz (frequency band = 2.78 GHz, fractional BW = 51.67%), 7.07-8.27 GHz (frequency band = 1.2 GHz, fractional BW = 15.65%), 9.14-12.44 GHz (frequency band = 3.3 GHz, fractional BW = 30.58%), 13.01-13.70 GHz (frequency band = 0.69 GHz, fractional BW = 5.17%) and 15.04-15.83 GHz (frequency band = 0.79 GHz, fractional BW = 5.12%). The proposed structure shows the wideband operation and the maximum fractional bandwidth of 51.67% is achieved. Hence, the proposed structure can be used for wideband applications for different bands. From Figure 5b it can be observed that the ISMeTM produces the SNG characteristics for the frequency ranges 5.46-6.29, 11.6-11.8, 13.8-15 and 15.8-16.8 GHz. The analysis validates the following: the values of the effective electric permittivity (\(\varepsilon_{r}\)) are negative; those of the magnetic permeability (\(\mu_{r}\)) are positive; and relative refractive index (\(\eta_{r}\)) are positive and negative within the same resonance frequency bands. As a result, these characteristics show that the proposed ISMeTM unit cell shows the MeTM properties. The proposed ISMeTM is useful for medical devices, optical filters, remote aerospace applications, and electromagnetic cloaking etc.