## 3 Results and Discussion
### Microwave Properties  
The main purpose to coat fabrics with conductive paste was to provide them with the function to shield EMR in microwave range likewise to absorb microwaves in radar operating range. A major threat to dismounted soldiers are battlefield radars commonly operating within X and Ku-bands at 8-12 GHz and 12-18 GHz, respectively [51]. Consequently, the investigation of reflection and transmission properties of developed textile fabrics was performed in a frequency range of 2-18 GHz, which cover the defined frequencies relevant to the application. The experimental data show the variation in EMR shielding effectiveness for four groups of coated fabrics over the tested range (Table 5 and Figure 7). For the uncovered fabrics (substrate samples), EMR shielding effectiveness SE (dB) was 0. All samples were coated with conductive paste (Table 3) in the equal conditions: the same screen, two layers (with intermediate drying) and thermo-fixation at 120 \({}^{\circ}\)C for 4 min. To shape the first layer, 4 passages were used and for the second, 2. However, the coating deposits were obtained different for each group of samples due to their particular structure (Table 1) and surface properties (wettability, moisture absorption and transport). With reference to obtained results, it could be stated that depending on such fabric structural parameters as--density, mass per unit area (or just mass), type of weave, as well as the apertures (pores), layer of shield (or coating) just sticks on the fabric surface or penetrates into fabric changing the shield thickness herewith turning SE results. Individually, for each type of fabric, the coating deposit and herewith the amount of conductive additive, PEDOT:PSS, have the most important impact on shielding properties. In our previous works [23], as well as during preliminary experiments for this study, SE determined as a function of coating deposit. For example, substrate S3 with increasing coating deposit--7 g/m\({}^{2}\), 14 g/m\({}^{2}\), 17 g/m\({}^{2}\), 24 g/m\({}^{2}\), demonstrated increased \(\mid\)SE \(\mid\) -- 10 dB, 15 dB, 20 dB, 25 dB, respectively. Similar correlation between coating deposit and shielding effectiveness was obtained for other fabrics under this study. For further investigations the fabrics with sufficiently high SE, but not exceeding 20 dB were selected, as it was found [5] that for radar absorbing only materials with total EMR SE below 20 dB were suitable. The data presented in Table 5 reports the average (dominant) SE values of coated fabrics with and without plasma treatment. As seen from results (Table 5 and Figure 7) EMR shielding ability for plasma treated samples in each group remain almost the same as for samples without plasma treatment, maybe with exception of wool samples (samples S1C and S1 PC). In the case of the last-mentioned samples, SE values for plasma treated sample (SIPC) is slightly higher in comparison with untreated sample (S1C) due to a bit increase in coating deposit. As can be seen from Figure 7, the shielding properties of coated samples are steady in all of the tested frequency range 2-18 GHz. Therefore, such a full side (in our case back