Slide 9 of 19

Notes:

The computed front-to-back ratio is plotted. The F/B peaks at nearly 30 dB at the design frequency, but exhibits a fairly narrowband characteristic, unlike the gain. This suggests that tuning of the array to achieve this theoretical F/B will be fairly critical. The turnaround in F/B near the high end of the band (2 MHz) does not have much significance since the radiation pattern becomes badly distorted and the gain in this region drops below 0 dBi.