Distributed antenna systems (DAS) have become a critical part of both enterprise infrastructure and carrier cellular networks. However, as technology evolved over the last 20 years, it has become increasingly complex. The list of acronyms alone can be overwhelming: iDAS, oDAS, eDAS, Active DAS, Passive DAS, Hybrid DAS, Off-air DAS, and numerous others. In this blog, we will describe some of the common types of distributed antenna systems.

In short, DAS is a network of antennas that send and receive cellular signals on a carrier’s licensed frequencies, improving voice and data connectivity for end-users. A distributed antenna system, as the name implies, distributes and enhances the existing signal.

Below, we dive into commonly used types of distributed antenna systems for enhancing network connection and ERRCS:

Passive DAS Solution

Passive DAS solutions are a more common approach that provides an amplified re-broadcasted signal from the carrier cell towers, using passive components like coaxial cable, splitters, and diplexers to distribute the signal. They also use bi-directional amplifiers to enhance and amplify signals from the macrocellular network using a donor antenna.

Because it is dependent on having a strong outside signal and using coaxial cables to distribute the signal, there are limitations to the use of passive DAS indoors, so it is typically used for smaller areas. The further the antennas are from the amplifier, the weaker the signal. These limitations mean that the coverage area for a passive DAS system is around 10,000 up to 500,000 sq ft.

However, the advantages of passive DAS solutions are noteworthy because it is considered the simplest approach in terms of design, is faster to deploy, and more cost-effective. In the next blog, we will analyze Active DAS and how it is used today.