What are Distributed Antenna Systems (DAS)?

August 3, 2023

Distributed Antenna System DAS

Things become highly overwhelming when you plan on knowing everything about DAS or Distributed Antenna Systems. It must be clearer to determine the best connectivity solutions for your establishment between expert explanations and technical terms. It is true since Distributed Antenna Systems or DAS technology have significantly evolved in recent times, leading to an entire range of options with their pros and cons.

Although the entire process of DAS is quite challenging, it is the main aspect of planning the requirements for the connectivity, mainly while 5G is already hitting the market. The solution you are picking impacts how you invest in this infrastructure and approach the cellular carrier contracts, along with the need for installation and the limitations to the capacity or coverage.

You must make the right architectural choices to support the company's activities now and in the future.

Fortunately, our team of experts at Metro Wireless is backed by years of experience installing the DAS and removing all the confusion. With this in your reminder, we have provided a comprehensive guide to the DAS antenna and associated technologies. You will get a thorough knowledge of the varied types of distributed antenna systems offered by the distributed antenna system companies, including the needs and perfect use.

About DAS or Distributed Antenna Systems

These days, around 80% of the daily smartphone data gets consumed indoors. As you have experienced, the cellular das services indoors have become spotty. The buildings constructed of concrete and specific metals make the things complex to capture a proper signal.

Fix Indoor Cellular Signal
Fix Indoor Cellular Signal

Adding the dead spots or the larger crowds can make things pretty complex. The dropped calls, weaker signals, and instant battery drainage will make your mobile experience far from the best.

Distributed Antenna Systems or DAS Systems are specifically designed to capture the cellular signal while distributing it in crowded outdoor or indoor venues. It benefits high-traffic areas like schools, shopping malls, subways, retail stores, convention centers, airports, businesses, and stadiums. The high-rise buildings and remote areas like the worksites can benefit greatly. 

With this being mentioned, DAS is even suitable for all businesses needing the proper coverage, and it is considered one of the broadest connectivity solutions available today.

 How Does Distributed Antenna System Work?

Importantly, DAS effectively captures the signals and supplies them to the distinctive space. The right setup for the DAS depends mainly on the distribution system and the signal source.

In one of the general situations, the DAS pulls the cellular das system signal from the rooftop antennas while channeling the signal through the coax cables to this amplifying unit. The unit improves the signals while running them throughout the building through the antennas and splitters.

Since there are various types of signal sources with the distribution systems to pick from with the setup of DAS, it might appear different in this instance. To aid you in wrapping your head around the different possibilities as we will take a deeper look at the different forms of systems and sources in the further post.

You should understand that DAS is the dedicated system to capture and supply the signal to the distinctive space with enhanced capacity and coverage.

Different Elements of Distributed Antenna Systems

DAS, or distributed antenna system, mainly comprises the following parts:

1. Signal source

For the distributed antenna systems to operate effectively, primary signal sources feed the DAS network for the signal required to get distributed. There are three signal sources: the base transceiver station or BTS, small cells, and off-air antennas.

Off-air antennas are highly cost-effective signal sources commonly used in commercial buildings in the middle of any urban district. Generally, the external antenna gets installed onto the building's roof while it sends and receives the signals to and from the macro cells, like the cell towers and carriers.

The BTS signal sources like the eNodeB, NodeB, and gNodeB are directly linked to the mobile operators through the fiber optic cables. These are the devices that perform better than the off-air antennas; however, the buildings and the venues are often installing one BTS for every carrier whenever the building occupants are using the varied network with the administration coordinates with the right network provider since the latter offers better access to the cable network of fiber optics.

The smaller cells would often function in a manner like the macro cells. They would amplify the wireless signals to extend the network coverage to almost every area of the building or venue, which is almost identical to how the modem extends the WiFi signal to the hidden areas of your commercial space.

2. Signal distribution system

Getting a stronger signal source is the initial step in establishing the distributed antenna systems, with the next move into implementing these antenna systems transmitting the signals and enhancing the connectivity through the building.

Nextivity CELFI DAS
Nextivity CELFI DAS

The signal distribution system performs three things: distribution, amplification, and broadcasting of the signals throughout this building. It is more than just extending the coverage while expanding the public network of the building with better capacities allowing the guests, occupants, visitors, and customers to get their mobile receptions.

The signals would often weaken in areas with higher densities since there are various other users. However, the strong distributed antenna systems can help the venues maintain stronger cellular services throughout the indoor and outdoor higher-density and low-density areas.

The technology that uses the signal distribution systems would define the kind of DAS a building uses. We will now look into the different kinds of antenna systems.

Types of Distributed Antenna Systems

1. Passive DAS

The passive DAS is their repeater that sends the signals through the couplers, coaxial cables, taps, and splitters to distribute the passive radio frequencies throughout the building or the venue. The passive DAS is often the best whenever you require extended coverage over the smaller areas and when the facility has thicker concrete, masonry, and the components for metal construction.

The passive DAS is the most cost-effective option as it is the simplest of the four distributed antenna systems. It would never need numerous components to operate as it is of low maintenance except for the longer coaxial cables that often suffer from signal weakening or attenuation and would often require timely replacement.

2. Active DAS

The active distributed antenna systems are more challenging than the passive DAS since the broadcast signals would undergo conversions. The active DAS comprises the master units and the RRUs or radio units, and the former would receive the RF or the analog radio frequency transmissions from these signal sources.

It would convert them to these digital signals before transmitting them to the RRUs throughout the building through the fiber optic cabling or ethernet. The RRUs convert these digital signals back into RFs so that Internet-connected devices or mobile phones can identify them.

As it uses fiber optics, the active DAS is the best for bigger venues with numerous structural barriers that impede signal distribution. The system can eventually convert the source signals into the light transmitted through the fiber optics while converting them back into identifiable RF signals after reaching the intended destination.

3. Hybrid DAS

As the name suggests, hybrid distributed antenna systems have started combining passive and active DAS technologies. They use fiber optics, RRUs, and coaxial cabling.

The hybrid DAS mainly captures the signals from the source using fiber optic cables instead of coaxial cables and sends them to the RRUs installed on every building floor. The RRUs are converting the light signals into RF while broadcasting them using the antennas connected to these RRUs through the coaxial cables.

The price point for the hybrid DAS system will sit between the active and passive DAS. They are extremely flexible while accommodating the scenarios where the active or the passive DAS answers this. Combining both offer the IT technicians better control over the transmission location and strength.

4. Digital DAS

Digital Distributed Antenna Systems are still in their infancy and have yet to be widely adopted. But, it is the general working principle as it does not do away with the RF-to-digital signal conversions while distributing these digital signals.

The Digital DAS uses the BBU or the baseband unit linking to the master unit, distributing the digital signals through the ethernet cables or the fiber optics. Although not using the RF, it is less susceptible to interferences. The IT technicians have a fixed capacity for the distinctive areas within the venue, like the conference hall, atrium, or cafeteria.

Digital DAS is very promising but expensive and works whenever the signal sources and the DAS master unit support the CPRI or the Common Public Radio Interface specifications.

The Future of DAS Technology

Active Passive Hybrid DAS
Active Passive Hybrid DAS

Although the smaller cells are getting adopted rapidly with the DAS technology surely sticking around, the main benefit includes greater capacity and coverage, multiple frequencies, and multi-careers, making DAS the number 1 connectivity solution for many. The Hybrid DAS would often become the prominent option while bringing together the best performances for the lowest installation cost.

With 5G heading to the mainstream, DAS becomes important for indoor connectivity. 5G gets deployed at higher frequencies than 4G and 3G. It is for this reason that indoor coverage becomes tougher and more complex with the 5G. Fortunately, DAS can offer the signal compared to the smaller cells.

Certainly, it is quite tough to predict the future of DAS and how it appears. For this reason, you should work with DAS experts like Metro Wireless to get updated advice on the solutions to 5G connectivity.

Enjoy Better Connection With DAS Partner!

Distributed Antenna Systems, or DAS, perfectly suit the company's requirements. It is important to connect with the DAS experts to create better connectivity plans, including the readiness for 5G.

You can now avail yourself of the complete turnkey DAS implementation that is well-tailored for the unique Boost office cellular signal situation. We will even take an expert step into the readiness of 5G, ensuring that your architecture is allowed for the roll-out of 5G. Our team of experts is prepared to build robust connectivity for your company, so connect with us today!