Study on feasibility of SATCOM for railway communication

Final Report
In order to provide an example, following data is assumed:
Data packet: 120 bytes
Transmission in return link: 5 kbps
Since the delay study is performed with the most restrictive channel, it will be made with the return channel.
Then, the end-to-end transmission packet delay in return link is:
T tx = packet_size / throughput = 120 bytes / 5000 bps = 192 ms
T rx = 1.5*T tx = 288 ms
T up = T down = sat_distance / speed = 36000 km / 300000 km/sec = 120 ms
This result shows that the low data rate along with the iterative processing at reception side causes a very high transmission delay.
Doc.Nº: SRAIL-FNR-010-IND
Edit./Rev.: 1/1
Date: 16/02/2017
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