Table 1.
Dimensions of PSG-RPA2 (FR4 substrate with h = 1.6 mm).
| Parameters | Lp | Wp | Wf | Lf | Lg | Wg | No. of polygon segments in PSG-RPA2 |
|---|---|---|---|---|---|---|---|
| Dimension | 36 mm | 16 mm | 0.5 mm | 2 mm | 20 mm | 28 mm | 18 |
Figure 1:
Geometry of the antenna. (A) Top view of the rectangular-patch antenna (RPA), (B) side view of RPA, (C) RPA with full ground plane, (D) PG-RPA, (E) PSG-RPA1 with a polygon cut with six segments, and (F) PSG-RPA2 with a polygon cut with 18 segments.
Table 2.
Parametric performance analysis of different design iterations (FR4 substrate is used).
| Parameter variation | Resonant frequency (GHz) | Impedance bandwidth (MHz) | Reflection coefficient (dB) |
|---|---|---|---|
| Conventional RPA | 4.02 | 30 | −10.64 |
| RPA with partial ground plane | 3.88 | 250 | −53 |
| RPA with hexagonal partial ground plane | 3.64 | 5.3 | −14.56 |
| RPA with polygon partial ground plane (proposed) | 3.41 and 3.83 | 700 | −26.17 and −31.15 |
| Variation of width of strip feed (Wf) in in RPA with polygon partial ground plane | |||
| 0.5 | 3.41 and 3.83 | 700 | −26.17 and −31.15 |
| 1 | 3.69 | 650 | −38.27 |
| 1.5 | 3.69 | 600 | −38 |
| 2 | 3.66 | 550 | −27.61 |
| 2.5 | 3.66 | 500 | −22.51 |
| 3 | 3.66 | 479 | −21.30 |
Figure 2:
Schematic configuration steps followed to reach our design geometry.
Figure 3:
Comparative analysis of the reflection coefficient for various design steps.
Table 3.
Comparison of simulated results of designed antennas, i.e., PSG-RPA1 and PSG-RPA2.
| Parameters | PSG-RPA1 | PSG-RPA2 |
|---|---|---|
| Lower cut-off frequency (fL) | 3.25 GHz | 3.28 GHz |
| Higher cut-off frequency (fH) | 3.75 GHz | 4.00 GHz |
| Bandwidth | 500 MHz | 720 MHz |
| VSWR (at 3.41 GHz) | 1.95 | 1.55 |
| VSWR (at 3.83 GHz) | 1.66 | 1.70 |
| Gain | 2.3 dB | 2.5 dB |
| Reflection coefficient | −13.35 dB | −31.15 dB |
Figure 4:
Voltage-standing wave ratio (VSWR) of the antennas PSG-RPA1 (bandwidth of ) and PSG-RPA2 (bandwidth of ).
Figure 5:
Radiation intensity for the proposed antenna with (A) E- and H-plane pattern of PSG-RPA1 at and (BW ) and (B) E- and H-plane pattern of PSG-RPA2 at and (BW ).
Figure 6:
Gain plot for the proposed antenna with (A) PSG-RPA1 (BW ) and (B) PSG-RPA2 (BW ).
Figure 7:
Antenna prototype of PSG-RPA2 (A) front view, (B) back view, and (c) measurement setup.
Figure 8:
Comparison of reflection-coefficient curves of simulated and measured designs for PSG-RPA2 possessing a bandwidth of .
Table 4.
Comparison of simulated and measured results of the PSG-RPA2 (FR4 substrate with ).
| Parameters | Simulated results | Measured results |
|---|---|---|
| Lower cut-off frequency (fL) (GHz) | 3.28 | 3.3 |
| Higher cut-off frequency (fH) (GHz) | 4.00 | 4.02 |
| Bandwidth (MHz) | 720 | 720 |
| VSWR (at 3.41 GHz) | 1.55 | 1.14 |
| VSWR (at 3.83 GHz) | 1.70 | 1.17 |
| Minimum reflection coefficient (dB) | −31.15 | −34.98 |
Table 5.
Comparison of our design with previous researches.
| Parameters | |||||
|---|---|---|---|---|---|
| References | Bandwidth (GHz) | Center frequency (GHz) | Patch size | Substrate parameters | Maximum gain (dBi) |
| Guo et al. (2011) | 2.6-6 | 4.3 | 0.78λ0 × 0.31λ0 | ∈r = 2.2, h = 0.01λ0 | ∽9 |
| Sekeljic et al. (2019) | 2.5-4.9 | 3.7 | 0.61λ0 × 0.24λ0 | ∈r = 4.4, h = 0.01λ0 | ∽4 |
| Tang et al. (2019) | 2.3-5.2 | 3.7 | 0.58λ0 × 0.23λ0 | ∈r = 2.5, h = 0.006λ0 | ∽3 |
| Shukla et al. (2016) | 4.0-9.7 | 6.8 | 0.68λ0 × 0.68λ0 | ∈r = 4.4, h = 0.03λ0 | ∽4 |
| Pathak and Singhal (2018) | 5.1-7.5 | 6.3 | 0.42λ0 × 0.31λ0 | ∈r = 4.4, h = 0.03λ0 | ∽2.8 |
| Proposed antenna PSG-RPA2 | 3.3-4.0 | 3.65 | 0.43λ0 × 0.19λ0 | ∈r = 4.4, h = 0.01λ0 | ∽2.5 |