SOURCEFORGE » RALF » 2014 ACM testing using channel emulation

h1. Newtec EL470

In the center spotlight of this project we have the Newtec EL470. It is a state-of-the-art satellite modem that is designed for transmission and reception of IP data over satellite links. Its maximum achievable rate is of 133Mbps strictly complying with DVB standards. It can be connected to IP network infrastructures via its available Gigabit Ethernet interfaces.Multiple encapsulation protocols are available, however, for this project we will use Newtec's proprietary XPE (Extended Performance Encapsulation). 

p=. !{width: 70%}newtecEL470.jpg!

Functionality overview:

• DVB-S2 and DVB-DSNG/S compliant.

• QPSK, 8PSK, 16APSK and 32APSK (unavailable in our setup).

• XPE, ULE, MPE, GSE, data piping encapsulation.

• Data rates up to 133 Mbit/s in each direction.

• Adaptive equaliser (demodulator input).

• L-band monitoring output.

• Programmable amplitude slope equalizer (L-band output).

• Noise & Distortion Estimator (NoDE) tool.

• DVB-S2 multi-stream.

• Embedded point-to-point ACM controller and ACM client (FlexACM).

ACM is implemented by using the embedded FlexACM client and controller options found in the HUB and Station modems respectively. We are however limited to a maximum modcod of 16APSK-9/10 due to licensing constraints. FlexACM allows for automatic and dynamic negotiation of configuration parameters in order to maximize bandwidth utilization. Its operation is further discussed in the [[FlexACM]] section. Following modcods are supported in our setup:

>Outer/Inner FEC: BCH/ LDPC

>MODCODS: QPSK: 1/4, 1/3, 2/5, 1/2, 3/5, 2/3, 3/4, 4/5, 5/6, 8/9, 9/10; 8PSK: 3/5, 2/3, 3/4, 5/6, 8/9, 9/10; 16APSK: 2/3, 3/4, 4/5, 5/6, 8/9, 9/10;

Each modem has an input and output as well as a monitor out (same as the output but different power level). All of these signals are in L-band.