When Distributed Antenna Systems were first evolving, all in-building wireless solutions used analog transport technologies. But over time and successive generations of DAS technology, these systems began to become digital-like. Solutions like CommScope's ION-E utilize full digital transport system, but before looking into the solution itself, we're going to clear up a few common misconceptions about digital DAS today.
1) First Misconception: If a vendor says that digital DAS runs on common public radio interface (CPRI), then it can connect to baseband units (BBU) via that CPRI.
Due to almost no vendors having CPRI connections to the BBU, and instead using a connection form the head-end to the remote areas, CPRI is being used as a system transport protocol within the DAS – not between the DAS and the BBU.
2) Second Misconception: Digital DAS does not have enough bandwidth to handle today's needs.
The greatest concern for any digital DAS user is being able to transport enough bandwidth. Digital systems traditionally transported less bandwidth due to how they work, but with the prevalence of multi-operator systems, digital DAS needs to handle more bandwidth. And it is more than possible to transport all that data, with a system that is spec'd for 10Gbps. To do so requires the use of the right cable, which can be seen below:
Category 5e operates at 100 Mbps, which is enough to transport a few RF channels.
Category 6 operates at 1,000 Mbps, which is enough to transport one or two licensed bands.
Category 6A reaches up to 10 Gbps, which is enough to transport all licensed bands.
3) Third Misconception: All digital DAS are essentially operating the same.
This is, like the others, false. There are differences in how much a digital DAS transports and how they transport. Thus, operators have a choice in what to transport. The best method would be to separate out and transmit only the RF channels that are in use within the band, so unused portions are not sent needlessly too.
To read more about these misconceptions, and about how CommScope's new digital DAS solutions are changing the market, click here, or contact your local Accu-Tech sales representative today for more information.