TEST REPORT Ku-Band LNB
LNBF for multifeed
If you ask a satellite fan what is most important
when choosing the right LNBF for the Ku-Band
reception system, you will most probably hear that
this is the conversion gain and the noise ﬁgure. The
ﬁrst should be as high as possible and the second on
the contrary: the lower the better. Most likely, all our
readers know that high conversion gain means that
the LNBF output signal level is high and thanks to
that long coaxial cables and signal splitters/switches
may be used without a fear that the signal will get
too weak for reception.
JIUZHOU SKYTRACK JSU33
Lightweight LNBF very suitable for
TELE-satellite Test Editor Jacek Pawlowski ■
mounts the new Skytrack LNB from
Jiuzhou to a regular offset dish pointing
to HOTBIRD at 13°E. The JSU33 LNB is
surprisingly small and lightweight
54 TELE-satellite & Broadband — 06-07/2009 — www.TELE-satellite.com
Download this report in
World from the Internet:
Arabic ﺍﻟﻌﺮﺑﻴﺔ www.TELE-satellite.com/TELE-satellite-0907/ara/jiuzhou.pdf
Indonesian Indonesia www.TELE-satellite.com/TELE-satellite-0907/bid/jiuzhou.pdf
Bulgarian Български www.TELE-satellite.com/TELE-satellite-0907/bul/jiuzhou.pdf
Czech Česky www.TELE-satellite.com/TELE-satellite-0907/ces/jiuzhou.pdf
German Deutsch www.TELE-satellite.com/TELE-satellite-0907/deu/jiuzhou.pdf
For the purpose of our test, English English www.TELE-satellite.com/TELE-satellite-0907/eng/jiuzhou.pdf
Spanish Español www.TELE-satellite.com/TELE-satellite-0907/esp/jiuzhou.pdf
we selected twelve transpond- Farsi ﻓﺎﺭﺳﻲ www.TELE-satellite.com/TELE-satellite-0907/far/jiuzhou.pdf
French Français www.TELE-satellite.com/TELE-satellite-0907/fra/jiuzhou.pdf
ers on HOTBIRD satellite (13° Greek Ελληνικά www.TELE-satellite.com/TELE-satellite-0907/hel/jiuzhou.pdf
East). Their parameters are Croatian Hrvatski www.TELE-satellite.com/TELE-satellite-0907/hrv/jiuzhou.pdf
Italian Italiano www.TELE-satellite.com/TELE-satellite-0907/ita/jiuzhou.pdf
listed in table 1. As you can Hungarian Magyar www.TELE-satellite.com/TELE-satellite-0907/mag/jiuzhou.pdf
Mandarin 中文 www.TELE-satellite.com/TELE-satellite-0907/man/jiuzhou.pdf
see, there are 3 transponders Dutch Nederlands www.TELE-satellite.com/TELE-satellite-0907/ned/jiuzhou.pdf
Polish Polski www.TELE-satellite.com/TELE-satellite-0907/pol/jiuzhou.pdf
for every sub-band (upper/ Portuguese Português www.TELE-satellite.com/TELE-satellite-0907/por/jiuzhou.pdf
Romanian Românesc www.TELE-satellite.com/TELE-satellite-0907/rom/jiuzhou.pdf
lower) and every polarization. Russian Русский www.TELE-satellite.com/TELE-satellite-0907/rus/jiuzhou.pdf
Swedish Svenska www.TELE-satellite.com/TELE-satellite-0907/sve/jiuzhou.pdf
In this way, we check the per- Turkish Türkçe www.TELE-satellite.com/TELE-satellite-0907/tur/jiuzhou.pdf
formance for both LOF’s: 9750 Available online starting from 29 May 2009
and 10600 MHz, both polariza-
tions: vertical and horizontal devices, for the four remain- ers, the output power was
and for the beginning, middle ing ones, it beat at least one bigger than the competitors.
Table 1. Transponders used and end of a sub-band. competitor and once even It is especially true for the
as test signals.
both (Tr-11). And yes, you are 0.3 dB which was the winner
The low noise ﬁgure should Figure 1 shows the noise per- right – the 0.2 dB device did in noise performance.
ensure good signal to noise formance of the devices. MER not seem to be better than
ratio at the output of LNBF, is a modulation error ratio – a 0.3 dB LNBF! That’s why we What conclusions you can
or more properly for digital
noise ratio. Low C/N is needed
to ensure the reception of
weaker transponders. It also
provides high margin for bad
weather conditions. Unfortu-
nately, the noise performance
of the real device is not that
easy to predict. Except for the
noise ﬁgure, there are other
parameters that inﬂuence the
These parameters are:
Fig. 1. MER for twelve different transponders of HOTBIRD satellite (13° East).
the phase noise of the local
oscillator of an LNBF and its parameter strongly related to explained earlier that the draw out of those results?
spurious content, reverse C/N and telling us how many noise ﬁgure itself is not the Skytrack JSU33’s strong point
polarization isolation, level bit errors are detected in the only parameter one must is its high output power. So it
of intermodulation, image incoming signal. Do we need take into account and only can be a preferred choice for
rejection. So, the only practi- to add that those errors are the real life test can reveal multi-satellite reception when
cal way to asses the LNBF is caused by noise? The better everything! we use multiswitches and
to apply it on a real antenna noise performance of an LNBF, long cable to distribute the
and make it receive real the higher MER values. And what about the other signal to many receivers. The
world signals. The presence parameter? It is presented in other advantage of this LNBF
of neighboring transponders While for 8 lower frequency ﬁgure 2. And here the situ- for multifeed system is its
makes life harder for an LNBF transponders, the noise per- ation is the opposite: it is lower proﬁle and weight (ca.
and degrades carrier-to-noise formance of the JSU33 was JSU33 that beat all the rest. 100 g) when compared with
performance. worse that the reference For 11 out of 12 transpond- other typical devices.
In a test like that, we com-
pare the actual perform-
ance of LNBF under test with
other LNBF’s available on the
market. That’s what we did
also when testing the LNBF
of Jiuzhou: Skytrack JSU33.
Its noise ﬁgure is speciﬁed
as 0.6 dB. We compared it
with 2 other contemporary
LNBF’s: one with NF speciﬁed
as 0.3 dB and the other with
NF=0.2 dB. Figure 2. Output power of the LNBF’s.
56 TELE-satellite & Broadband — 06-07/2009 — www.TELE-satellite.com
Lightweight, low proﬁle LNBF very suitable
for multifeed installations. High output power is
another advantage in this application. Good work-
It will not be a choice for a DX- er.
Manufacturer Shenzhen Xiangcheng Electric Technology Co., Ltd.
E-mail firstname.lastname@example.org / email@example.com
Telephone +86 755 26715445/26947236
Fax +86 755 26947266/26715408
Function Universal Ku-Band Single LNB
Input Frequency 10.7 GHz – 12 GHz
Output Frequency 950 MHz – 2150 MHz
LOF Initial Accuracy 1 MHz @ 25°C
LOF Thermal Drift 2 MHz (-30 ~ +60°C)
Noise Figure 0.6 dB max. @ 25°C
Conversion gain 60 dB min.
DC Current consumption 120 mA max.
58 TELE-satellite & Broadband — 06-07/2009 — www.TELE-satellite.com