COMPLEX OF SATELLITE VIDEOCONFERENCE
KIEV / KYIV, UKRAINE
Regime: “point – to multi points”.
In regime: “point – to multi points” the work of the complex is conducted as follows.
On computers of VSAT Distant Earth Stations (DES) programme “videoserver” is configured for the coding working conditions and transfer of video and audio data.
On the VSAT -Central Earth Satellite Station (CESS) a programme “videoserver” is configured for reception and decoding of video and audio data.
A transmission of data from DES to CESS is conducted as follows:
On a VSAT - CESS a signal of the main broadcasting programme
is UpLink-ed in DVB-S MPEG-2 standard, which brings an information in its stream:
data ( remote control of VSAT - DES stations)
Remote control of VSAT - DES stations is based on control of the following equipment:
Satellite L band modem DT 8000;
programme of coding-decoding of a “video server”.
On the first stage the personnel of the remote VSAT DES station conducts tuning of their antenna in direction of satellite and necessary tuning of their MPEG-2 DVB-S receiver/decoder, by parameters sent by CESS operator. After finishing with the mentioned operations, all further control of the parameters of
VSAT DES station are available form the center, i.e. from CESS. That is why an CESS operator takes all control over parameters.
Control commands from CESS received by receiver/decoder MPEG-2 DVB-S, are transmit to
VSAT - DES to its
“server control“ programme. An operator of CESS, from his desk-top enters parameters for satellite modem DT-8000 of
VSAT - DES. After checking stand-by data, an operator conducts a command of signal UpLink this
VSAT DES to the satellite. During this time a CESS operator controls the situation on the satellite transponder by specter analyzer.
On the second stage, when a procedure of UpLink of the remote VSAT DES station to the satellite is finished and correctness of CES parameters is checked, a start of a video-server programme comes for the same
VSAT DES station.
“Videoserver” programme captures video signal (composit or s-video) from video-cards and also captures audio from a sound-card. These cards are installed on the computer of remote DES station. After it, an operation system of a
VSAT DES computer forms a stream, which consists of:
data of “chat-programme”.
A “chat-programme” provides a communication between personnel of CESS and personnel of DES via “Internet Explorer”.
Outer source of a video and audio signal for the correcponding video and audio cards, installed on
VSAT DES computer is a TV-camera/camcorder.
In this way a data stream is formed, which will consist of a destination address (“vedeoserver” programme of the CESS). This stream is transmit by a net-card on router CISCO-1005, which transfers a srteam from transport protocol TCP/IP (UDP) to OSPF protocol. Then data of OSPF protocol are transmit to the satellite modem DT-8000, which conducts an additional noises protection coding of data and then transfers them to the modem of CESS by a satellite communication channel.
On the receiving side, a satellite modem CM-601 recieves data and sends them further to the router CISCO-1005. Router CISCO-1005 transfers data from OSPF protocol to TCP/IP (UDP) protocol. Control system of CESS controls activity of interface of router CISCO-1005 and in case of its activation this programme locates a number of a remote DES station, which was added to CESS station. Then a temporary ID will be given to a newly added station, after that data are transferred to a “videoserver” programme for a decoding of video and audio signals.
Decoded video and audio signals are sent to the main programme of MPEG-2, which is formed by a CESS, after a decision of an editor. For communication of the CESS with personnel of a remote DES an internal audio-signal and chat programme is used.