There’s been a growing trend in the international and Australian markets to ensure multi-tenant buildings, shopping centres, airports, train stations, hotels, hospitals, etc., can provide seamless mobile coverage for their customers.

There are two main technologies that can be deployed to achieve in-building mobile coverage: small cell and DAS.

But which is the right technology?

To answer this question let’s briefly explain each.

Small cell technology

As the name suggests, this technology addresses small footprints in buildings where sufficient mobile coverage can’t be achieved with the existing macrocells and/or microcells infrastructure.

Picocell and/or metrocell solutions are two of the conventional methods for deploying in-building mobile coverage as part of the small cell architecture. These solutions are still being used.

However, small cell technology does have limitations.

The downside of the Picocell solution is that it can only support one mobile carrier, with limited frequency support.

The equipment is invariably proprietary and the solution is architected for small spaces like homes or small offices, as opposed to large enterprise buildings and campuses.

DAS technology

The distributed antenna system (DAS) architecture is one of the most common in-building mobile coverage technologies.

It’s used to extend mobile coverage where there’s a gap in macro mobile coverage.

Two types of DAS technology are being used in commercial buildings: passive DAS and active DAS.

Passive DAS

In this technology there’s no active equipment.

The radio frequency is distributed to remote areas by means of amplifiers and coaxial cabling to a remote antenna.

Deployment of this technology is recommended for medium-sized single-tenanted buildings where limitation with the length of coaxial cable run isn’t an issue.

Active DAS

In this technology, active equipment is used to extend the mobile coverage through a building via a number of antennas.

Regardless of the geometry of the building, equal mobile coverage can be achieved due to the fact that the RF signal doesn’t degrade. Each remote antenna can be adjusted individually without any implication on the overall system.

Unlike passive DAS, fibre or Cat6 cables are used as a high-capacity signal transport medium, connecting each remote unit to their hub and head-end system.

Above all, active DAS is a solution that can be fully managed by operators and has the following advantages:

• supports multiple carriers in a single antenna system
• web-based network management for monitor and control
• centralised power supply options for remote units.

So which is the best technology to use?

Both small cell and DAS technologies are still being used globally for provision of in-building mobile coverage.

However, for a high-end business environment, small cell technology isn’t the ideal solution.

Considering the importance of connectivity and business continuity in large campuses and high-rise buildings, DAS is the most practical technology to consider.

While a passive DAS solution may be a suitable option for single-carrier support for medium-sized buildings, the issues with ongoing maintenance and lack of the appropriate level of monitoring system inhibit considering it for greenfield buildings.

As the cost of fibre reduces and reliance on single backbone connectivity for multiple carriers become more practical, the advantages of an active DAS solution outweigh those from other solutions.

Active DAS is the key to seamless mobile coverage in commercial buildings and big campuses such as airports, shopping centres and hospitals.

It also provides a far better flexibility and manageability.