EVLA Memo 123 The Effect of the 4-Band Dipoles on L, C, and X Band Performance
نویسنده
چکیده
Test observations show that the deployable 4-band dipoles degrade VLA antenna sensitivity by approximately 7% at L-band, 8% at C-band, and 6% at X-band. The loss at higher frequencies is unknown, but is expected to be less. The dipoles also introduce a variability of 1 – 3% in the antenna cross-polarization at L-band only. This variability will degrade L-band polarimetry capabilities, limiting its accuracy to ∼1%.
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