- Turkish Journal of Electrical Engineering and Computer Science
- Vol: 28 Issue: 2
- A multibeam subarrayed time-modulated linear array
A multibeam subarrayed time-modulated linear array
Authors : Uğur Yeşilyurt, Ihsan Kanbaz, Ertuğrul Aksoy
Pages : 784-798
Doi:10.3906/elk-1904-201
View : 6 | Download : 2
Publication Date : 9999-12-31
Article Type : Makaleler
Abstract :In conventional time-modulated arrays TMAs , because of the usage of the RF-switch, harmonics are generated at multiples of the modulation frequency. In this study, the synthesis of time-modulated arrays has been analyzed for cognitive radio CR systems, in which these harmonics are suitably exploited for more efficient utilization of the spectrum. In order to accomplish the desired pattern at requested harmonic frequencies, a new excitation strategy with sinusoidal signals is proposed. The use of sinusoidal waveforms creates independent beams, allowing independent steering capability. Moreover, by utilizing the subarray structure, it is possible to have a smaller number of excitation functions in the hardware. It is shown by means of explanatory examples that the effectiveness of the proposed approach is due to free-adjustable beamforming, beam steering, and low complexity.Keywords : Time-modulated arrays, subarrayed antennas, sideband radiation, harmonic beamforming, beam steering, cognitive radio