High-performance, low-cost fibre optic delay lines for analog applications

✍ Scribed by P. Myslinski; C. Szubert; R. Misner; J. Lee

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 256 KB
• Volume: 20
• Category: Article
• ISSN: 0895-2477
• DOI: 10.1002/(sici)1098-2760(19990205)20:3<173::aid-mop7>3.0.co;2-t

✦ Synopsis

Figure 8 Results in the H-plane for the developed array as ob-Ž . Ž . tained at 1.8 GHz. a Ensemble simulation. b Experimental results

corporate feed network with additional phase shifts to tilt the main beam 30Њ toward the ground. The design process has been aided by the antenna CAD software packages Ensemble and PCAAD. The antenna has been constructed and tested. Experimental results have shown that the developed antenna achieves the required impedance bandwidth and 30Њ beam tilt. However, the experimental sidelobe level is higher than that predicted by the theory. Also, the backward radiation is more significant than predicted. Further experimentation is required to reduce the sidelobe and back-lobe levels to a more reasonable level. One possible remedy is to use a nonuniform taper that will reduce the sidelobes. The undesired backward radiation can be reduced using dog-bone shaped apertures and by introducing a back short behind the antenna structure.