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Orbital X-Band Professional Series
Series LNBs
1. Built-in Tx
suppression Filter X-band VSAT systems have
very narrow TX/TR spacing. (Rx:
7.25 - 7.75 GHz,
Tx:7.9 - 8.4GHz). Because of this frequency
spacing, LNB performance degradation such as
3rd order Inter-modulation (Im3) and Noise
Figure is likely due to Tx leakage into the
Rx path. Orbital has taken design measures
to avoid these Tx interferences specifically
by placing a Tx suppression filter in the
LNB. The rejection filter is placed at an
interstage of the LNB’s LNA and Tx leakage
is suppressed more than 35dB over
temperatures of -40 to +60 deg C. The result
of the Tx suppression filter, IM3 issues
produced by Rx and leaked Tx is resolved and
NF degradation caused by Tx thermal noise is
negligible with excellent image rejection of
greater than 60dB.
2.
High Output P1dB and IP3 Orbital LNBs have
excellent linearity. Output compression
point (P2dB) is greater than +15dBm and
third order intermodulation intercept point
(IP3) is +25dBm or greater.
3.
Low Input VSWR Orbital is able to provide
the optionally very low input VSWR LNB.
Generally, LNBs are designed to optimize
noise figure and as a result of this
optimization, input VSWR increases To avoid
the “Long Line Effect” between the antenna,
feed components and LNB, Orbital places a
waveguide isolator in front of the LNB
giving a VSWR of 1.2 : 1. The isolator also
decreases LO leakage by about 20 dB and
creates unconditional stability under all
conditions while adding minimal insertion
loss. The X-band LNB is also available
without the isolator, thus giving an
increase in VSWR to 2 : 1, but getting an
improvement in noise figure by removing the
loss of the isolator. |
