Insat 4B at 93.5°E-Indian beam : DD Direct plus & spectrum analysis
Insat 4B at 93.5°E-DD Direct plus : footprint , measurement point , HF system ...
.
Insat 4B at 93.5°E -Indian beam in KU band : measurements taken in the town of Lučenec / central Slovakia
a, geographical location : Latitude: 48.33° _ Longitude: 19.72°
b, measurement results are derived from the 3.7 m diameter antenna
c, ground without obstacles in the horizon length to 1000 m
d, date of measurement : 19.2.2011
e, elevation angle : 2.0°
d, weather conditions : cloudy with rain !!!
e, air temperature : from 0 to 5 °C
f, altitude : 185 m /asl
g, installation period and aggregation measured data : from 7.00 to 16.00 p.m.
.
- Practice verified signal coverage before and after the failure of the satellite during the summer of last year 2010 -
Asia , Middle East , East & Central & parts of Southern Europe : before Dmin=200-250+ cm and now Dmin=270-450+ cm
Central Africa : possibility of stable reception for all packets from the network DD Direct plus is excluded up to 800 cm
diameter antenna
.
--- Insat 4B at 93.5°E-footprint : theoretically defined satellite footprint for KU band ---
/ Antrix corporation limited India /
- with a high degree of probability, I can confirm that the satellite Insat 4B radiating diagrams for C and KU bands cover
nearly identical parts of the earth's surface but with different high radiated power.Compared with the C-band diagram
radiated power decreases in the KU band much faster north-westerly direction on the European continent, as confirmed
by the results of my measurements.Until the beginning of a satellite failure I reached in reception in the C and KU bands
exceptionally high gain levels with a zero level of BER before vitterbi decoder for several transfers .
click for enlarge
--- Insat 4B at 93.5°E : HF system , geographical location of measurement ---
.
installed HF system theoretical footprint research point
a, PF Prodelin 3.7 m a, state : Slovak republic / Europe
b, UNI LNB : NF=0.4-0.6 dB b, town : Lučenec
d, cable lenght : 40 m c, geo. location : 48.33°_19.72°
.
Insat 4B at 93.5°E-DD Direct plus : analysis of the spectrum from 10 950 to 11 150 MHz_V
.
--- Insat 4B at 93.5°E-DD Direct plus : spectrum analysis of the vertical vector from 10 950 to 11 150 MHz ---
click for enlarge
--- reception status of 19.2.2011 ---
10 990 > 11 150 : even in bad weather conditions (cloudy with rain) I have identified a stable form of lock on the three
carrier with a permanently oscillating gain margin in the range from MER=1.5 to 4 dB & bBER=1x10-3 > 9x10-3 .In this
case is significantly reflected low sensitivity of measuring devices (Rover,Unaohm) with the detection threshold of 2 dB
higher than normal receiver brands Vantage !
.
Insat 4B at 93.5°E-DD Direct plus : analysis of the spectrum from 11 450 to 11 700 MHz_V
.
--- Insat 4B at 93.5°E-DD Direct plus : spectrum analysis of the vertical vector from 11 450 to 11 700 MHz ---
click for enlarge
--- reception status of 19.2.2011 ---
11 490 - 11 570 MHz : average gain margin for the two carrier in this part of the spectrum was about MER=1.5 to 2 dB lower
than at carrier in the first part of the spectrum and at a significantly bad weather conditions there is an irregular increase
in uncorrected RS blocks-RU.(applies only to measuring instr. Rover,Unaohm).Current satellite receivers from the
commercial sector detect these packets without instability or downtime.
.
Insat 4B at 93.5°E-DD Direct plus : full spectral range of vertical vector_10 950 >11 750 MHz
.
--- Insat 4B at 93.5°E-DD Direct plus : spectrum analysis of the vertical vector from 10 950 to 11 750 MHz ---
click for enlarge
DD Direct plus 10 990+11 070+11 150 MHz & SUN Direct HD 11 030 MHz :analysis of the V vector at the research point
.
Insat 4B at 93.5°E-DD Direct plus : author's research activities in the field of wave physics
.
--- Insat 4B at 93.5°E-DD Direct plus : Two PEAK MEMORY function - after the failure of the satellite ---
before modification in the waveguide / 15.8.10 after the modification in the waveguide
time frame : 30 sec time frame : 1 200 sec
amplitude of oscillations significantly negates the quality also at significantly degraded weather conditions there is
of reception and in the time frame every thirty seconds no shortfall in the carrier lock and reception quality oscillates
there is a shortfall in reception only in the gain range .
.
Modification of the waveguide, which has a direct relationship with a significant decrease in amplitude of oscillation.
I applied the same principle when received a packet Dish TV from NSS 6 satellite at 95.0°E .
.
After more than five years of research work in the reception wave of satellites with the elevation angle of only 2 degree
above zero, which falls into the category of wave physics, I come to a result which completely deny my initial conclusions
on the direct relationship between the size of the elevation angle and the presence of continuously oscillating signal
levels in a wide amplitude range, which I was associated with the reflector antenna noise temperature and noise
temperature of the earth etc. My calculations would confirm the high quality factor antenna, which I derived from the
ratio of G / T, that is based on a theoretical perspective should be final quality of earnings during an elevation angle
of only one degree less significantly degraded as I identified in measurements in recent years research activities.
So I am not able to put into action a high quality factor antenna derived from the ratio of G / T, which is in this type
of antenna with nearly ideal ratio f / D (0.37 vs 0.4) significantly less degraded antenna noise temperature factor.
A turning point in my research activities took place six months ago when I understood the direct relationship between
the position sensors waves in waveguides and permanent oscillation, which significantly degraded the quality of
reception from the orbital position 93.5°E - EA=2° and 95°E - EA=1° .
Then I understood and applied this change in the waveguide,permanent oscillation of all transponders in India
footprint reduced by 75%, as evidenced by the PEAK MEMORY analysis.
.
Insat 4B at 93.5°E-DD Direct plus: live recordings from the analysis and the carrier lock
.
--- DD Direct plus : spectrum of vertical vector in the range of 10 990 to 11 150 MHz_01---
.
--- DD Direct plus : spectrum of vertical vector in the range of 11 490 to 11 570 MHz_02---
CZECH & SLOVAK DX SATELLITE CLUB
international professional portal
Think-Tank
Roman Dávid - author & founder
mail : roman.david@dxsatcs.com