DVB-S2The User Experience

David TaylorSatSignal Software

Edinburgh

DVB-S2

• Requirements– Antenna & LNB– Receiver

• Making the transition• Resolving problems you may encounter• Outstanding issues• Still to come…

Antennas

• The new satellite footprint is weaker• The bandwidth is larger• A better signal-to-noise is required• So ….• …. a bigger antenna may be required

LNB

• A critical component• Don’t believe a 0.1 dB noise factor!• Need a low-noise LNB

– Extensive tests by Arne van Belle– Inverto Black Ultra IDLB-TWNL40-ULTRA-OPP

• Adjust skew for best Es/No• Adjust focus (move LNB in and out)

Receivers

• PCIe card inside your PC – single PC– TBS 6925 & TBS 6983

• External USB box – single PC– TBS 5925 – software still relatively new

• External IP receiver – serves many PCs– Ayecka SR 1– Novra S300E– … and others

PCs• DVB-S2 may stress your PC more,

especially the High Volume Service• There may be compatibility issues with

some PCIe cards and some PCs– Suck it and see approach!

• IP receivers need a network port– May need a second network card, and one

with up-to-date drivers– Try Edimax Ethernet-to-USB 2.0 adapter

Making the transition

• Start with DVB-S• Set up your new receiver• Re-point the antenna• Switch to DVB-S2

Starting with DVB-S

• Assume you have a working DVB-S system looking at the 9° East satellite

• Study receiver options and decide which is best for you – USB, PCI card, IP RX

• Procure DVB-S2 receiver• Run in parallel with your existing receiver

Setting up the receiver

• For Ayecka, Novra & TBS EUMETSAT provide configuration guides

• Ayecka and Novra configuration files are provided, automating the setup over a USB or network link

• TBS setup is currently a much more manual process, which may require 3rd party software running on your PC

Setting up the PC

• IP receivers – 2nd network card– Either: add second network card or Ethernet-

USB adapter & configure its address– Or: Wi-Fi connect the PC Wi-Fi, use existing

LAN port– Connect Management port to house LAN

• USB/PCIe receivers– Follow configuration guide for the device

Configuring TelliCast

• Just one step!– Edit your recv.ini file to point to the new

network device (card or virtual device)– But not the IP Receiver’s address!

Re-pointing the antenna

• Change between 9° East and 10° East will depend where you are, a little east and very slight elevation change

• Having peaked on 9A originally, tweak the disk azimuth just a little, then optimise both azimuth and elevation

• Use a professional meter, or watch the graphical output from the Ayecka or other software.

Can I still get DVB-S?

• Antenna has only moved a small amount, so likely you will still get enough DVB-S signal to continue with the service

• Ayecka particularly easy to switch between the services

LNB adjustment

• Adjust the skew (rotation) of the LNB for best signal-to-noise. Objective is to reduce the amount of cross-polarised signal received from other transponders

• Adjust the focus of the LNB (in and out) for best SNR

• Keep tweaking!

Switching to DVB-S2

• Ayecka – already has two receiver configuration sets programmed so just make setting 2 (DBV-S2) active

• Novra – re-run the configuration process selecting the DVB-S2 CFG file

• TBS – type in all the new RF and PID configuration details

• Edit recv.ini if not already done before

What can possibly go wrong!

• Dish issues• Network issues

LNBs too far apart

LNB fallen off

LNB pointing in the wrong direction

Wrong IP address

• Tempting to use the address of the IP receiver when editing recv.ini.

• Not right! You need the address of the network card in the PC.

• Not the address of the sender• But the address of the receiving card

Not using a separate network

• The full EUMETCast stream which comes out of the IP Receiver will saturate a Wi-Fi or 100 Mb/s network.

• So use a separate LAN• Not complicated – simply connect a

network lead between the IP Receiver and a port on your PC.

• Or use a small switch like Netgear GS605 for multiple PCs.

Using poor cables or 100 Mb/s network

• Using 100 Mb/s switch and random cables, found some odd missed packet events in early tests, but most packets recovered.

• Not seen since using 1 Gb/s switch and 1 Gb/s LAN cards.

• Should check cables are “gigabit” certified.• Cat 5E likely good enough.

Need to wake network card?• On one PC, found the need to PING the remote receiver

before starting TelliCast.• Perhaps the LAN port sleeps even though UDP packets

are present?

• Solved with a simple .CMD file:– PING <LAN adapter>– Wait a little– PING <SR 1 receiver>– Wait a little– Start tc-recv.exe

Problems seeing the network?

• TelliCast may have problems identifying which network to use.

• Solve by:– Setting the network address to 0.0.0.0 in

recv.ini– Leaving out the interface_address altogether

Outstanding Issues – 1

• Lower Link Margin– Because of small antenna or rain fade

• When taking Basic & HV services– Link margin becomes too low for HVS– Results in many errors on the Basic Service

• Arne van Belle has done many tests

Resolving Lower Link Margin

• Fix – change Ayecka receiver settings:– Tweak the thresholds, low: 0.6 high: 0.7 dB

• Fix – prevent HVS reception– Ayecka, set dual receiver mode– TBS requires software setting, but

BDADataEx doesn’t allow this– Novra receiver?

Outstanding Issues – 2

• The High Volume Service?– Problems taking BS & HVS on one receiver?– Receiver, driver or TelliCast resolution?

• Request for more open and complete information about HVS tests– Changes seen but not announced?– Need to know the number of files being sent

so we can check whether all files are received

Outstanding Issues – 3

• The new TelliCast software– Resolve multicast join/leave problem?– Beta test programme?– Signed Java application?

• Support– PC & OS requirements?– Compatibility with disk defragmenters– Compatibility with NTFS file system– Easy to update?

Acknowledgements

• To Ayecka, Novra, TBS and GEO for procuring test receivers.

• To EUMETSAT for answering many questions and providing extensive User Guides

• To David Simmons, Alan Banks, Arne van Belle, Douglas Deans, James Brown, Ernst Lobsiger, and others for their testing and for discovering some of the issues and asking helpful questions!