Table 7 Detailed comparison of latest technology of microstrip filtenna with the existing literature
# | Ref. | Size \(({\text{mm}}^{2})\) | Range of operating frequencies (GHz) | Tuning band (GHz) | Tuning diodes numbers | Efficiency | Gain (dBi) |
|---|---|---|---|---|---|---|---|
1 | [2] | \(60 \times 80\) | 1.3–3 | 1.7 | 4 varactor diode | NA | NA |
2 | [3] | \(45 \times 42.5\) | 2.37–3.69 | 1.33 | Single varactor diode | 60% | 1.37 |
3 | [15] | \(80 \times 100\) | 2.2–3.4 | 1.2 | Single varactor diode | NA | NA |
4 | [20] | \(25 \times 15\) | 3.3–4.2 | 0.9 | 2 PIN diode | 50% | 3.5 |
5 | [21] | \(39 \times 42\) | 3.63–4.7 | 1.07 | 2 PIN diode | NA | 2 |
6 | [32] | \(80 \times 80\) | 1.75–3 | 1.25 | 4 varactor diode | NA | 4.5 |
7 | [33] | \(80 \times 110\) | 1–1.6 | 0.6 | NA | NA | 2.64 |
8 | [34] | NA | 1.57–1.86 | 0.31 | NA | NA | 5 |
9 | [35] | \(30 \times 59.8\) | 6.16–6.6 | 0.44 | Single varactor diode | NA | NA |
This work | \(25 \times 35\) | 1.93–3.56 | 1.63 | Single varactor diode | 60% | 2.26 | |