C-band Sats – Part 4: 115.5E ChinaSat 6B, 120E AsiaSat 6, 122E AsiaSat 9

In part four of the series, I continue my C-band satellite hunting adventure by moving up the belt. This post looks at 115.5 degrees East (ChinaSat 6B), 120 degrees East (AsiaSat 6) and 122 degrees East (AsiaSat 9).

115.5°E ChinaSat 6B

ChinaSat 6B is a fairly popular satellite amongst Chinese audiences as it carries a multitude of provincial TV stations from China direct to home. It seems to be one of the more active satellites in terms of number of watchable free-to-air services, however, almost all of it is standard definition and in Chinese. It aims at servicing the China main-land but also covers into south-east Asia and Australia.

The satellite makes use of the extended C-band, but some of it is lost due to interference. Lots of active carriers – the BLscan report is quite daunting to read, with a wide variation in received SNR. Many of the services seem to be similar to SCPC arrangements, possibly uplinked directly from the provincial TV station directly.

TP N: 1
Frequency: 3546.631 Mhz
Symbol rate: 3699 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S2/QPSK
FEC: 3/4
RollOff: 0.35
Pilot: off
Coding mode: CCM
Long frame
Transport stream
Single input stream
RF-Level: -45 dBm
Signal/Noise: 10.5 dB
Carrier width: 4.994 Mhz
BitRate: 5.504 Mbit/s
----------------------------------------
TP N: 2
Frequency: 3601.038 Mhz
Symbol rate: 27499 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 7/8
RollOff: 0.35
RF-Level: -41 dBm
Signal/Noise: 12.3 dB
Carrier width: 37.124 Mhz
BitRate: 44.350 Mbit/s
----------------------------------------
TP N: 3
Frequency: 3641.046 Mhz
Symbol rate: 27499 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 7/8
RollOff: 0.35
RF-Level: -40 dBm
Signal/Noise: 13.1 dB
Carrier width: 37.124 Mhz
BitRate: 44.350 Mbit/s
----------------------------------------
TP N: 4
Frequency: 3680.999 Mhz
Symbol rate: 27499 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 7/8
RollOff: 0.35
RF-Level: -40 dBm
Signal/Noise: 12.8 dB
Carrier width: 37.124 Mhz
BitRate: 44.350 Mbit/s
----------------------------------------
TP N: 5
Frequency: 3710.482 Mhz
Symbol rate: 10919 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -42 dBm
Signal/Noise: 14.8 dB
Carrier width: 14.741 Mhz
BitRate: 15.095 Mbit/s
----------------------------------------
TP N: 6
Frequency: 3740.981 Mhz
Symbol rate: 27499 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -39 dBm
Signal/Noise: 12.8 dB
Carrier width: 37.124 Mhz
BitRate: 38.014 Mbit/s
----------------------------------------
TP N: 7
Frequency: 3750.993 Mhz
Symbol rate: 10489 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -41 dBm
Signal/Noise: 14.3 dB
Carrier width: 14.161 Mhz
BitRate: 14.501 Mbit/s
----------------------------------------
TP N: 8
Frequency: 3771.141 Mhz
Symbol rate: 12359 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S2/8PSK
FEC: 3/5
RollOff: 0.20
Pilot: off
Coding mode: CCM
Long frame
Transport stream
Single input stream
RF-Level: -41 dBm
Signal/Noise: 10.9 dB
Carrier width: 14.831 Mhz
BitRate: 21.999 Mbit/s
----------------------------------------
TP N: 9
Frequency: 3797.157 Mhz
Symbol rate: 6929 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 1/2
RollOff: 0.35
RF-Level: -43 dBm
Signal/Noise: 12.8 dB
Carrier width: 9.355 Mhz
BitRate: 6.386 Mbit/s
----------------------------------------
TP N: 10
Frequency: 3807.957 Mhz
Symbol rate: 5999 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -42 dBm
Signal/Noise: 13.7 dB
Carrier width: 8.099 Mhz
BitRate: 8.294 Mbit/s
----------------------------------------
TP N: 11
Frequency: 3809.031 Mhz
Symbol rate: 8799 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -42 dBm
Signal/Noise: 9.1 dB
Carrier width: 11.879 Mhz
BitRate: 12.165 Mbit/s
----------------------------------------
TP N: 12
Frequency: 3816.120 Mhz
Symbol rate: 4420 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -41 dBm
Signal/Noise: 11.9 dB
Carrier width: 5.967 Mhz
BitRate: 6.110 Mbit/s
----------------------------------------
TP N: 13
Frequency: 3817.171 Mhz
Symbol rate: 3166 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -44 dBm
Signal/Noise: 9.8 dB
Carrier width: 4.275 Mhz
BitRate: 4.378 Mbit/s
----------------------------------------
TP N: 14
Frequency: 3826.066 Mhz
Symbol rate: 6779 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -41 dBm
Signal/Noise: 11.2 dB
Carrier width: 9.152 Mhz
BitRate: 9.372 Mbit/s
----------------------------------------
TP N: 15
Frequency: 3835.067 Mhz
Symbol rate: 5399 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -41 dBm
Signal/Noise: 12.0 dB
Carrier width: 7.289 Mhz
BitRate: 7.465 Mbit/s
----------------------------------------
TP N: 16
Frequency: 3841.063 Mhz
Symbol rate: 27499 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -38 dBm
Signal/Noise: 13.0 dB
Carrier width: 37.124 Mhz
BitRate: 38.014 Mbit/s
----------------------------------------
TP N: 17
Frequency: 3847.042 Mhz
Symbol rate: 5949 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -41 dBm
Signal/Noise: 12.6 dB
Carrier width: 8.032 Mhz
BitRate: 8.225 Mbit/s
----------------------------------------
TP N: 18
Frequency: 3855.061 Mhz
Symbol rate: 4419 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -41 dBm
Signal/Noise: 12.7 dB
Carrier width: 5.966 Mhz
BitRate: 6.110 Mbit/s
----------------------------------------
TP N: 19
Frequency: 3862.106 Mhz
Symbol rate: 4799 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -40 dBm
Signal/Noise: 13.1 dB
Carrier width: 6.479 Mhz
BitRate: 6.635 Mbit/s
----------------------------------------
TP N: 20
Frequency: 3872.074 Mhz
Symbol rate: 9079 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -39 dBm
Signal/Noise: 11.5 dB
Carrier width: 12.257 Mhz
BitRate: 12.551 Mbit/s
----------------------------------------
TP N: 21
Frequency: 3881.100 Mhz
Symbol rate: 27498 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -35 dBm
Signal/Noise: 13.4 dB
Carrier width: 37.123 Mhz
BitRate: 38.013 Mbit/s
----------------------------------------
TP N: 22
Frequency: 3886.117 Mhz
Symbol rate: 4340 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -41 dBm
Signal/Noise: 13.6 dB
Carrier width: 5.859 Mhz
BitRate: 6.000 Mbit/s
----------------------------------------
TP N: 23
Frequency: 3893.093 Mhz
Symbol rate: 4420 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -40 dBm
Signal/Noise: 12.2 dB
Carrier width: 5.967 Mhz
BitRate: 6.110 Mbit/s
----------------------------------------
TP N: 24
Frequency: 3903.128 Mhz
Symbol rate: 9299 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -39 dBm
Signal/Noise: 11.6 dB
Carrier width: 12.554 Mhz
BitRate: 12.856 Mbit/s
----------------------------------------
TP N: 25
Frequency: 3914.104 Mhz
Symbol rate: 6399 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -40 dBm
Signal/Noise: 11.5 dB
Carrier width: 8.639 Mhz
BitRate: 8.847 Mbit/s
----------------------------------------
TP N: 26
Frequency: 3921.143 Mhz
Symbol rate: 27499 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -32 dBm
Signal/Noise: 13.6 dB
Carrier width: 37.124 Mhz
BitRate: 38.014 Mbit/s
----------------------------------------
TP N: 27
Frequency: 3930.108 Mhz
Symbol rate: 8839 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -39 dBm
Signal/Noise: 12.2 dB
Carrier width: 11.933 Mhz
BitRate: 12.220 Mbit/s
----------------------------------------
TP N: 28
Frequency: 3941.077 Mhz
Symbol rate: 5949 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -37 dBm
Signal/Noise: 13.4 dB
Carrier width: 8.032 Mhz
BitRate: 8.225 Mbit/s
----------------------------------------
TP N: 29
Frequency: 3951.088 Mhz
Symbol rate: 11406 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 5/6
RollOff: 0.35
RF-Level: -37 dBm
Signal/Noise: 12.5 dB
Carrier width: 15.398 Mhz
BitRate: 17.520 Mbit/s
----------------------------------------
TP N: 30
Frequency: 3952.072 Mhz
Symbol rate: 9520 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -37 dBm
Signal/Noise: 10.7 dB
Carrier width: 12.852 Mhz
BitRate: 13.160 Mbit/s
----------------------------------------
TP N: 31
Frequency: 3962.076 Mhz
Symbol rate: 3572 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -38 dBm
Signal/Noise: 10.9 dB
Carrier width: 4.822 Mhz
BitRate: 4.938 Mbit/s
----------------------------------------
TP N: 32
Frequency: 3972.092 Mhz
Symbol rate: 9999 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -36 dBm
Signal/Noise: 12.7 dB
Carrier width: 13.499 Mhz
BitRate: 13.823 Mbit/s
----------------------------------------
TP N: 33
Frequency: 3981.075 Mhz
Symbol rate: 27499 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -27 dBm
Signal/Noise: 13.2 dB
Carrier width: 37.123 Mhz
BitRate: 38.013 Mbit/s
----------------------------------------
TP N: 34
Frequency: 4001.077 Mhz
Symbol rate: 27495 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -27 dBm
Signal/Noise: 13.7 dB
Carrier width: 37.119 Mhz
BitRate: 38.009 Mbit/s
----------------------------------------
TP N: 35
Frequency: 4021.095 Mhz
Symbol rate: 27499 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -27 dBm
Signal/Noise: 12.9 dB
Carrier width: 37.123 Mhz
BitRate: 38.013 Mbit/s
----------------------------------------
TP N: 36
Frequency: 4041.144 Mhz
Symbol rate: 27499 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -27 dBm
Signal/Noise: 10.7 dB
Carrier width: 37.124 Mhz
BitRate: 38.014 Mbit/s
----------------------------------------
TP N: 37
Frequency: 4061.072 Mhz
Symbol rate: 27499 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -30 dBm
Signal/Noise: 12.9 dB
Carrier width: 37.124 Mhz
BitRate: 38.014 Mbit/s
----------------------------------------
TP N: 38
Frequency: 4069.155 Mhz
Symbol rate: 9982 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -39 dBm
Signal/Noise: 10.6 dB
Carrier width: 13.476 Mhz
BitRate: 13.800 Mbit/s
----------------------------------------
TP N: 39
Frequency: 4101.098 Mhz
Symbol rate: 27499 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -35 dBm
Signal/Noise: 11.3 dB
Carrier width: 37.124 Mhz
BitRate: 38.014 Mbit/s
----------------------------------------
TP N: 40
Frequency: 4116.661 Mhz
Symbol rate: 21373 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -40 dBm
Signal/Noise: 11.1 dB
Carrier width: 28.854 Mhz
BitRate: 29.546 Mbit/s
----------------------------------------
TP N: 41
Frequency: 4136.098 Mhz
Symbol rate: 4339 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -43 dBm
Signal/Noise: 12.3 dB
Carrier width: 5.858 Mhz
BitRate: 5.999 Mbit/s
----------------------------------------
TP N: 42
Frequency: 4141.109 Mhz
Symbol rate: 27500 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -38 dBm
Signal/Noise: 11.8 dB
Carrier width: 37.125 Mhz
BitRate: 38.015 Mbit/s
----------------------------------------
TP N: 43
Frequency: 4148.142 Mhz
Symbol rate: 6148 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -43 dBm
Signal/Noise: 10.6 dB
Carrier width: 8.300 Mhz
BitRate: 8.500 Mbit/s
----------------------------------------
TP N: 44
Frequency: 4159.111 Mhz
Symbol rate: 8680 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -43 dBm
Signal/Noise: 9.9 dB
Carrier width: 11.718 Mhz
BitRate: 11.999 Mbit/s
----------------------------------------
TP N: 45
Frequency: 4172.071 Mhz
Symbol rate: 9199 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -43 dBm
Signal/Noise: 10.1 dB
Carrier width: 12.419 Mhz
BitRate: 12.718 Mbit/s
----------------------------------------
TP N: 46
Frequency: 4176.059 Mhz
Symbol rate: 17999 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 1/2
RollOff: 0.35
RF-Level: -41 dBm
Signal/Noise: 12.4 dB
Carrier width: 24.299 Mhz
BitRate: 16.588 Mbit/s
----------------------------------------
TP N: 47
Frequency: 4193.114 Mhz
Symbol rate: 5999 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -43 dBm
Signal/Noise: 13.3 dB
Carrier width: 8.099 Mhz
BitRate: 8.294 Mbit/s
----------------------------------------
Total Scan Time = 1186.104s

The summary of services is as below:

Most of the services were SD resolution using DVB-S modulation which makes receiving the services on cheaper/older equipment possible.

Interesting Signals

The above is the spectrum in horizontal and vertical respectively. Despite carrying a lot of TV services, it seems that most of the TV services are in the standard C-band area to maximise the chances of reception. The extended C-band appears to have some narrow services.

The above is centred at 3660.94Mhz in the horizontal polarity, and there are a lot of narrow carriers, some 6-9dB stronger than others.

The above is centred at 3621.87Mhz in the horizontal polarity, showing that the narrow data services seem to be packed in quite closely in some parts with very little guard band (near the centre). There are also two wider carriers that seem to have a very steep roll-off as well – quite impressive.

More of the same at 3582.26Mhz horizontal …

… and at 3641.3Mhz horizontal …

… and at 3420.6Mhz horizontal. In this particular example, we can see the local terrestrial LTE interference in better detail, showing how it makes it almost impossible to clearly see the services underneath, except for when the transmission goes “silent” in-between bursts.

Similar services are found in the vertical as well, at 3441.52Mhz …

… at 3482.38Mhz in the vertical …

and at 3570.24Mhz, right next to a wider DVB-S type carrier. Notably, all of the services identified seem to continuously transmit, and are likely to be FDMA or CDMA rather than TDMA.

Beacons

A beacon in the horizontal was found at 4200.153Mhz, modulated with telemetry. It looks to be a AM with a wide FSK subcarrier at 65khz, and an outer unmodulated subcarrier at 131khz.

The subcarrier shift appears to be about 9khz.

Looking at it over a longer span of time seems to show some frames of telemetry have repeating data or idle symbols possibly, which come up as a static pattern.

A beacon with much the same signal parameters was found in the vertical, at 3702.089Mhz. This seems to match with expectations based on data from FrequencyPlanSatellites.

120°E AsiaSat 6

AsiaSat 6, also known as Thaicom 7 is at 120 degrees East and provides coverage over a wide area of Asia. It doesn’t seem to have many television services at the moment, mainly carrying SiTV.

A scan of the regular C-band using CrazyScan shows a few clearly defined carriers, with a few uneven patches which might be interference from the nearby AsiaSat 9, just two degrees away. The BLscan resulted in only a few services:

TP N: 1
Frequency: 3901.110 Mhz
Symbol rate: 29499 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -36 dBm
Signal/Noise: -10.0 dB
Carrier width: 39.824 Mhz
BitRate: 40.779 Mbit/s
----------------------------------------
TP N: 2
Frequency: 3929.120 Mhz
Symbol rate: 9579 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -37 dBm
Signal/Noise: -10.0 dB
Carrier width: 12.932 Mhz
BitRate: 13.243 Mbit/s
----------------------------------------
TP N: 3
Frequency: 4101.090 Mhz
Symbol rate: 29499 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -35 dBm
Signal/Noise: 12.4 dB
Carrier width: 39.824 Mhz
BitRate: 40.779 Mbit/s
----------------------------------------
TP N: 4
Frequency: 4141.030 Mhz
Symbol rate: 29499 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -35 dBm
Signal/Noise: 12.1 dB
Carrier width: 39.824 Mhz
BitRate: 40.779 Mbit/s
----------------------------------------
TP N: 5
Frequency: 4181.072 Mhz
Symbol rate: 29499 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -38 dBm
Signal/Noise: 12.5 dB
Carrier width: 39.824 Mhz
BitRate: 40.779 Mbit/s
----------------------------------------
Total Scan Time = 1719.430s

A summary of the services are as follows:

Interesting Signals

The spectrum in horizontal above, and vertical below. Interestingly, there seems to be a few spikes which implies potential beacons.

There were a few different data services in the vertical at 3926.85Mhz. The left pair seem to be slotted TDMA type. In the spase area to the right, there seems to be a very low duty burst-transmission system.

At 3794.56Mhz in the horizontal polarity, I spotted this carrier which seemed to sweep across a bandwidth of about 25.5Mhz width in 20 seconds on a repetitive basis. I’m not sure what it’s used for – maybe it’s ranging? Maybe it’s an experiment? Maybe it’s interference? Maybe it’s oscillation?

Beacons

At the low-end of the RF, in the horizontal polarity, there seemed to be two fairly strong CW tones which may be beacons at 3699.543266Mhz and 3702.549516Mhz (spaced 3Mhz apart, seemingly deliberate).

At the high-end of the RF, there seemed to be a few beacons – the higher one may be circular polarity as it appears strong even through switching polarities, whereas the lower one appears to be vertical (image depicts switching from vertical to horizontal).

A closer look shows two telemetry beacons which have lots of constant data/idle times. The frequencies appear to be:

  • 4199.793002Mhz (V, modulated)
  • 4200.891002Mhz (CP, modulated)

The beacon at 4199.79Mhz seems to have two main data subcarriers, with a few stray lines (intermodulation? or weaker subcarriers?). The frequencies are 48kHz with a 10khz shift and 72khz with about 9khz shift.

The beacon at 4200.89khz has an inner unmodulated subcarrier at 16khz and an outer subcarrier at 48khz with a 10khz shift.

122°E AsiaSat 9

AsiaSat 9 is a recently launched (29 Sept 2017) satellite that replaced AsiaSat 4 at the 122 degrees East slot. I’ve been meaning to look at this satellite in detail as soon as possible, as the new satellite usually means improved capacity and potentially new services. Unfortunately, it still seems not to be used for much TV broadcast, so maybe there’ll be a lot of other services to look at.

The satellite seems to put out a pretty good signal in the standard C-band range. There seems to be a lot of signal intensity across the CrazyScan spectrum, with the BLScan reporting a number of lockable DVB-S/S2 type transmissions.

TP N: 1
Frequency: 3703.963 Mhz
Symbol rate: 1599 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S2/QPSK
FEC: 1/2
RollOff: 0.35
Pilot: on
Coding mode: CCM
Short frame
Transport stream
Single input stream
RF-Level: -45 dBm
Signal/Noise: -10.0 dB
Carrier width: 2.159 Mhz
BitRate: 1.581 Mbit/s
----------------------------------------
TP N: 2
Frequency: 3840.842 Mhz
Symbol rate: 29999 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S2/8PSK
FEC: 3/4
RollOff: 0.35
Pilot: off
Coding mode: CCM
Long frame
Transport stream
Single input stream
RF-Level: -36 dBm
Signal/Noise: 12.9 dB
Carrier width: 40.499 Mhz
BitRate: 66.868 Mbit/s
----------------------------------------
TP N: 3
Frequency: 3901.033 Mhz
Symbol rate: 26659 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -33 dBm
Signal/Noise: 15.1 dB
Carrier width: 35.990 Mhz
BitRate: 36.853 Mbit/s
----------------------------------------
TP N: 4
Frequency: 3975.735 Mhz
Symbol rate: 5331 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S2/QPSK
FEC: 2/3
RollOff: 0.20
Pilot: on
Coding mode: CCM
Long frame
Transport stream
Single input stream
RF-Level: -41 dBm
Signal/Noise: 8.5 dB
Carrier width: 6.397 Mhz
BitRate: 7.053 Mbit/s
----------------------------------------
TP N: 5
Frequency: 3980.995 Mhz
Symbol rate: 26659 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -28 dBm
Signal/Noise: 13.5 dB
Carrier width: 35.990 Mhz
BitRate: 36.853 Mbit/s
----------------------------------------
TP N: 6
Frequency: 4015.573 Mhz
Symbol rate: 5036 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 7/8
RollOff: 0.35
RF-Level: -34 dBm
Signal/Noise: 14.3 dB
Carrier width: 6.799 Mhz
BitRate: 8.123 Mbit/s
----------------------------------------
TP N: 7
Frequency: 4020.984 Mhz
Symbol rate: 29999 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S2/QPSK
FEC: 1/2
RollOff: 0.35
Pilot: off
Coding mode: CCM
Long frame
Transport stream
Single input stream
RF-Level: -25 dBm
Signal/Noise: -10.0 dB
Carrier width: 40.499 Mhz
BitRate: 29.669 Mbit/s
----------------------------------------
TP N: 8
Frequency: 4035.748 Mhz
Symbol rate: 12499 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S2/QPSK
FEC: 5/6
RollOff: 0.20
Pilot: off
Coding mode: CCM
Long frame
Transport stream
Single input stream
RF-Level: -31 dBm
Signal/Noise: 8.4 dB
Carrier width: 14.999 Mhz
BitRate: 20.686 Mbit/s
----------------------------------------
TP N: 9
Frequency: 4121.019 Mhz
Symbol rate: 29719 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S2/8PSK
FEC: 5/6
RollOff: 0.20
Pilot: on
Coding mode: CCM
Long frame
Transport stream
Single input stream
RF-Level: -35 dBm
Signal/Noise: 10.2 dB
Carrier width: 35.663 Mhz
BitRate: 73.673 Mbit/s
----------------------------------------
TP N: 10
Frequency: 4140.987 Mhz
Symbol rate: 29999 KS
Polarization: Vertical
Spectrum: Normal
Standard/Modulation: DVB-S2/8PSK
FEC: 5/6
RollOff: 0.20
Pilot: on
Coding mode: CCM
Long frame
Transport stream
Single input stream
RF-Level: -37 dBm
Signal/Noise: 11.4 dB
Carrier width: 35.999 Mhz
BitRate: 74.368 Mbit/s
----------------------------------------
TP N: 11
Frequency: 4156.889 Mhz
Symbol rate: 2169 KS
Polarization: Horizontal
Spectrum: Normal
Standard/Modulation: DVB-S/QPSK
FEC: 3/4
RollOff: 0.35
RF-Level: -42 dBm
Signal/Noise: 12.2 dB
Carrier width: 2.929 Mhz
BitRate: 2.999 Mbit/s
----------------------------------------
Total Scan Time = 2215.106s

A summary of the services are as follows.

This particular satellite proved to be a boon for a number of reasons. The first was the UHD Test channel – one of very few UHD broadcasts on the air in any means.

The SNR was quite borderline, but sufficient to watch the H.265 HEVC encoded broadcast. It runs a loop of content which includes a few programs from 4kUNIVERSE and demos from Rhode & Schwarz, AsiaSat, etc lasting roughly three hours.

Above, a still frame from the AsiaSat promo video where it shows the inside of their earth station at Tai Po, Hong Kong with the overlaid 4K-SAT logo. While the carrier does allow for about 70Mbit/s payload rate, the actual stream is only about ~17.6Mbit/s on the video (Main [email protected]@Main profile HEVC) + 160kBit/s MPEG-1 Layer 2 stereo 48Khz audio.

Other interesting services include what appears to be an ACM/VCM service with generic stream and “idle” blob.

This service which is identified as QPSK with CCM but also having a lot of idle symbols and difficulty maintaining a lock. It’s probably a VCM stream that somehow got locked by the Prof 8000 which cannot support VCM.

Likewise, this seems to be a 16APSK stream which the Prof 8000 cannot lock, but seems to do a decent job of plotting for analysis.

Interesting Signals

As usual, the spectrum of the signals in the horizontal and vertical are displayed respectively. Most of the activity on this satellite that we can receive in Australia is in the horizontal.

At 3701.09Mhz in the horizontal, there are a number of discontinuous data services which implies TDMA type access. The width of the carrier is about 300khz on the left-most, with some even being half that width moving towards the middle. Wider data services lie to the right of the centre, but it seems that each bank has a “reference” frequency pilot CW tone being sent (three in the image) to help the slave stations get their frequency reference.

The majority of the other data services are in the vertical polarity, the above at 4178.96Mhz. This one seems to show a slotted TDMA access regime, but the surprise is that it seems to show an intermixing of different carrier widths. Maybe they’re all different independent systems lining up one-next-to-another. Some of them show notable modulation in the intensity during a transmission burst – maybe there’s clouds in the way? Towards the right, a set of five wider data services are packed side by side so closely that the gaps are hardly visible. Another narrow service may be to the left of the edge causing “protruding fingers” to appear. It’s actually quite beautiful.

Then, there is this system at 3681.20Mhz which uses very short transmission bursts and various frequencies adjacent to each other with subtle differences in widths. Each burst, when the peak hold trace is examined, has two spectral peaks on the outer edges. Maybe this is a sign of a type of FSK? It reminds me of the FHSS nature of Bluetooth, but I’m not sure whether they are independent systems or part of a single system.

This type is again visible at 3659.56Mhz, with fewer carriers and a different configuration. I suspect they are independent systems judging by the loading of the channels.

This, at 3942.54Mhz, shows a wide data carrier on the right that has a spectral pattern when idling, which is disrupted when data is transmitted. This seems to be a pretty common system, as it’s been seen before.

Beacons

At the high end of the spectrum, two beacons were seen in the horizontal polarity. These are 4199.690831Mhz and 4200.692331Mhz, separated by ~1Mhz and modulated.

Both beacons follow a similar set-up, with the left showing wide FSK subcarriers at 128.5khz and 320.5khz with 32khz shift. The exception is that the left, higher frequency beacon, seems to have an inner unmodulated/low-rate PSK modulated beacon at (possibly) 16khz.

The frame length seems to be about 450mS.

There are a few CW lines in the vertical, but it seems unlikely to be beacons given the weak signal strength.

This one seemed stronger in the vertical, but I’m not sure if it is intended to be a beacon or not. Its frequency was 3690.95Mhz.

Conclusion

ChinaSat 6B is one of the most heavily-loaded satellite in terms of broadcast video that I have come across in recent times and was the regular “home” position for this dish. AsiaSat 6 didn’t have much of interest except for a strange sweeping signal phenomenon. AsiaSat 9 was one that I was highly anticipating, delivering an interesting 4K-SAT demonstration channel and a few interesting-looking data services, but otherwise not being too exciting. There’s plenty more C-band satellites visible in the sky to hunt for …

About lui_gough

I'm a bit of a nut for electronics, computing, photography, radio, satellite and other technical hobbies. Click for more about me!
This entry was posted in Satellite, Telecommunications and tagged , , , , . Bookmark the permalink.

Error: Comment is Missing!