Network Technologies DVB-ASI to IP Options, 1PPS/10MHz interface modules, 2 1PPS interface

ASI-IP-GTW User's Manual

4 Options

This chapter describes functionality and operating instructions for various additional product options.

4.1 1PPS/10MHz interface modules

In order to achieve exact bitrate control for use in SFN networks, the ASI-IP-GTW may be equipped with 1PPS/10MHz interface modules. The purpose is to lock the internal system clock of the ASI-IP-GTW to external 1PPS/10MHz signals to obtain exact bitrate control. The typical application is to receive a stream over IP network and send it out on ASI connectors at a fixed, accurate rate. The transmitter needs to transmit at the same rate.

Two options exist to lock the product to external time reference: A separate 10MHz/1PPS module which occupies an ASI slot, or a separate 1PPS input module that allows 8 ASI ports.

4.1.1 Separate 10MHz/1PPS module

Figure 29 shows a picture of the back panel when this module is mounted.

Figure 29. ASI-IP-GTW with 1PPS/10MHz interface module equipped

The signals are:

o10MHz. 50 ohm terminated input for a sinusoidal 10MHz signal. o 1PPS. 50 ohm TTL input for a 1 pulse-per-second signal.

For physical parameters of these ports, see appendix B.

Both signals may be connected. However, the ASI-IP-GTW only uses one of them at a time. The active input is selected from the “GPS” tab in the ASI-IP-GTW WEB user interface.

4.1.21PPS interface

When 8 ASI outputs are required together with SFN operation, an alternative to the 1PPS/10MHz module is to use a separate 1PPS interface as described in the following figure.

Figure 30. ASI-IP-GTW with separate 1PPS interface module

The signals are:

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