Single- and double-beam reflectarrays for Ka band communication

• Published in: Sadhana (Bangalore) 2019-05, Vol.44 (5), p.1-13, Article 106
• Main Authors: ELSHARKAWY, RANIA, HINDY, MOATAZA, SEBAK, A -R, SALEEB, ADEL, EL-RABAIE, EL-SAYED M, RAGHEB, AMR, ASHRAF, MUHAMMAD, ALSHEBEILI, SALEH
• Format: Article
• Language: English
• Subjects: Angle of reflection; Bandwidths; Design; Engineering; Extremely high frequencies; Horn antennas; Satellite communications; Sidelobes; Simulation
• ISSN: 0256-2499; 0973-7677
• DOI: 10.1007/s12046-019-1109-x

The Ka band has found applications in satellite, and radar communications. It is also expected that this band will be utilized for 5G applications. This paper presents single- and double-beam microstrip reflectarrays with single layer and compact size for Ka band communications at 28 GHz. Three different unit cells are investigated in this paper. Single- and double-beam reflectarrays are investigated. The reflectarrays are designed at 28 GHz with a physical size of 10λ × 10λ. A pyramidal horn antenna is used for the feeding purpose. The focal-length-to-diameter (F/D) ratio is equal to one. Two different scenarios for single-beam reflectarrays are presented: one with a broadside direction and the other with a 10° tilt angle. The simulation results show that for the broadside single-beam scenario, it is possible to achieve a gain up to 28.5 dB, and a 1-dB gain-bandwidth up to 30.7%. On the other hand, the presented reflectarray for the single-beam design at 10° tilt angle gives a gain of about 26.4 dB, a side lobe level (SLL) of about −15.6 dB, and a 19.3% gain-bandwidth. For the double-beam reflectarray, four different designs at different angles of 5°, 10°, 15°, and 20° have been simulated and compared. Moreover, the simulation results on the double-beam reflectarray show that the double-beam design at 10° is better from the gain and SLL perspectives. Two prototypes for broadside single-beam reflectarrays have been fabricated and measured. The measurement results show a good match with the simulation results. Gain flatness is guaranteed for both the simulated and measured results over the band of interest.