Aspects of Efficiency Enhancement in Reflectarrays with Analytical Investigation and Accurate Measurement
Abstract
:1. Introduction
2. Loss Quantification of Reflectarray Antenna
3. Background of the Common Techniques of Efficiency Improvement in Reflectarrays
3.1. Elements with Low Loss and Wide Reflection Phase Range
3.2. Sub-Wavelength Elements for Loss Reduction
3.3. Strategic Feeding Mechanism for Aperture Loss Reduction
3.4. Some Advanced Types of Reflectarray
4. Factors Affecting the Aperture Efficiency of the Circular Aperture Reflectarray Antenna
4.1. Effects of Different Feeds on the Aperture Efficiency
4.2. The Effect of Different Feed Distances on the Aperture Efficiency
4.3. The Effect of the Feed Footprint on the Aperture Efficiency
5. Aperture Efficiency of the Square Aperture Reflectarray Antenna
5.1. Aperture Efficiency of the Conventional Square Aperture
5.2. Aperture Efficiency of the Square Aperture in a Diamond Shape
5.3. Aperture Efficiency Comparison between Circular and Square Aperture Reflectarrays
6. A Practical Method to Accurately Predict and Measure the Efficiency of a Reflectarray Antenna
6.1. Design and Analysis of the Pyramidal Horn Feed
6.2. Design Characteristics of the Unit Cell Patch Element
6.3. Design and Validation of the Circular and Square Aperture Reflectarrays
6.4. Efficiency Prediction by Gain-Directivity Relation
6.5. Efficiency Prediction by Loss Quantification
7. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Element Type | Design | Loss (dB) | Phase Range (°) | Aperture Size (λ2) | Efficiency (%) |
---|---|---|---|---|---|
Hexagonal [42] | N.A | 360 | 69.4 | 60 | |
Bow-tie [22,43] | −0.4 | 360 | 39 | 57 | |
I-Shaped [20] | N.A | 360 | 75.7 | 50 | |
Dual Rings [44] | N.A | 360 | 250 | 52 | |
Parallel Dipoles [45] | −0.2 | 360 | 180 | 65 | |
Two Rings and Patch [46] | N.A | 360 | 130 | 64 | |
Three Rings [23] | N.A | 500 | 163 | 66 | |
Split Ring [47] | −0.3 | 360 | 187 | 55 | |
Fractal [48] | −0.45 | 700 | 54.5 | 66 | |
Ring with Phase Delay Lines [49] | −0.05 | 460 | 78 | 57.3 |
f/D | q | Max. Aperture Efficiency (%) | Feed Beamwidth (°) |
---|---|---|---|
0.4 | 2 | 50 | 66 |
0.5 | 3 | 57 | 55 |
0.6 | 4.5 | 62 | 45 |
0.7 | 5.5 | 66 | 41 |
0.8 | 7 | 69 | 36 |
0.9 | 9 | 71 | 32 |
1.0 | 11 | 73 | 29 |
1.1 | 13 | 74 | 27 |
1.2 | 15 | 75 | 25 |
1.3 | 17.5 | 76 | 23 |
Parameter | Circular Aperture | Square Aperture | |
---|---|---|---|
Predicted | Max. Directivity (dB) | 29.94 | 31 |
Simulated | Gain (dB) | 27.03 | 27.2 |
Efficiency (dB) | −2.91 (51.2%) | −3.8 (41.7%) | |
Measured | Gain (dB) | 27.3 | 27.4 |
Efficiency (dB) | −2.64 (54.4%) | −3.6 (43.6%) |
Type of Loss | Circular Aperture | Square Aperture | ||
---|---|---|---|---|
Simulated | Measured | Simulated | Measured | |
Feed (dB) | −0.1 | −0.36 | −0.1 | −0.36 |
Patch (dB) | −0.7 | −0.84 | −0.7 | −0.84 |
Illumination (dB) | −0.91 | −1.19 | −1.96 | −2.21 |
Spillover (dB) | −1.3 | −0.41 | −1.3 | −0.41 |
Total (dB) | −3.01 | −2.8 | −4.06 | −3.82 |
Total Efficiency | 50% | 52.5% | 39.3% | 41.5% |
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Dahri, M.H.; Jamaluddin, M.H.; Seman, F.C.; Abbasi, M.I.; Sallehuddin, N.F.; I. Ashyap, A.Y.; Kamarudin, M.R. Aspects of Efficiency Enhancement in Reflectarrays with Analytical Investigation and Accurate Measurement. Electronics 2020, 9, 1887. https://doi.org/10.3390/electronics9111887
Dahri MH, Jamaluddin MH, Seman FC, Abbasi MI, Sallehuddin NF, I. Ashyap AY, Kamarudin MR. Aspects of Efficiency Enhancement in Reflectarrays with Analytical Investigation and Accurate Measurement. Electronics. 2020; 9(11):1887. https://doi.org/10.3390/electronics9111887
Chicago/Turabian StyleDahri, M. Hashim, M. Haizal Jamaluddin, Fauziahanim C. Seman, M. Inam Abbasi, N. Fazreen Sallehuddin, Adel Y. I. Ashyap, and M. Ramlee Kamarudin. 2020. "Aspects of Efficiency Enhancement in Reflectarrays with Analytical Investigation and Accurate Measurement" Electronics 9, no. 11: 1887. https://doi.org/10.3390/electronics9111887