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ArcLight Hub User’s Guide
Component Operating Procedures
Rev. 001 1081006 5-53
6 Transmitted phase noise mask
When using the specified FLM reference, the
transmitted phase noise shall not exceed the levels
shown below.
Freq offset
100 Hz: -70 dBc/Hz
1 kHz: -80 dBc/Hz
10 kHz: -90 dBc/Hz
> 100kHz: -100 dBc/Hz
7 Transmitted phase deviation from
linear phase shift.
< +/-4 degrees
The specification shall be verified over the specified
frequency tuning range (see 3).
It is expected that the modulation will be performed
digitally and that the signal will be filtered using a
SAW BPF prior to transmission.
SAW filters are generally specified for phase ripple
rather then group delay because the phase ripple,
although small, rapidly varies thus producing a
large, though inconsequential, group delay
measurement.
8 Out of band emissions
When using the specified FLM reference, the
transmitted spectral density shall not exceed the
levels shown below. This specification includes the
effect of harmonics and spurs.
2
a
o
BW
f
≤
0 dB/4kHz
a o
a
BW f
BW
≤ <
2
-25dB/4kHz
a o a
BW f BW
⋅ ≤ <
5 . 2
-35dB/4KHz
o a
f BW
< ⋅
5 . 2
-60dB/4KHz
o
f
is the magnitude of the frequency offset from the
carrier center frequency e.g. if the center frequency is
70MHz and
a
BW
= 36MHz, then the power must be
down 60dB beginning at 160MHz.
An exception to this specification is described by the
2
nd
harmonic rejection requirement.
9 2
nd
harmonic rejection Because of the SAW filter used for alias suppression,
a 2
nd
harmonic of the transmitted spectrum is
expected. The spectral PSD shall be limited as
follows;
-40dB/4KHz in the range
a a
BW MHz f BW MHz
+ ≤ < −
140 140
Note that if
a
BW
= 36MHz, the combination of the
location of the 60dB down point, the Ku-band
upconverter filtering, and the harmonic specification
will ensure specification compliance.