How to fix poor indoor mobile coverage.

Modern construction is the primary culprit. Materials designed to make buildings energy-efficient, Low-E glass, reinforced concrete, metal cladding, foil-backed insulation, also block radio signals. A metallic coating on a window that's designed to reflect heat reflects mobile signal just as effectively. Reinforced concrete can reduce signal strength by over 35 dB at common 4G frequencies, enough to turn reliable outdoor coverage into a dead zone indoors.

The challenge compounds with every barrier. A signal that passes through an exterior wall, then an internal partition, then another partition loses strength at each one. By the time it reaches the core of the building (lifts, stairwells, basements) there may be nothing usable left.

Mobile towers are optimised for broad outdoor coverage. Highways, suburbs, CBD streetscapes. The signal you receive indoors is usually whatever's left over after reaching the building and passing through the envelope. Network operators do consider buildings in their planning, but serving every floor of every building from an outdoor tower isn't practical.

In dense urban areas, antennas are often down-tilted to avoid overshooting the street, which means upper floors rely on weaker fringe signal arriving at shallow angles. Tall buildings can also sit in the overlapping footprint of multiple towers, where competing signals cause interference that degrades quality even when signal strength looks adequate on your phone.

In regional areas, the challenge is distance. Fewer towers means weaker signal at the building, and less to work with once it passes through the walls.

As mobile networks evolved, they became increasingly reliant on higher frequency bands. In Australia, 3G operated on 850 MHz and 900 MHz, 4G began on 1800 MHz, 5G on 3500 MHz. Operators move up the spectrum because wider channel bandwidths are available at higher frequencies, which is how they deliver faster speeds and handle more users. The trade-off however is that higher frequencies penetrate building materials less effectively. A building that had adequate 3G coverage on 850 MHz may have had poor 4G on 1800 MHz and no usable 5G on 3500 MHz. The building hasn't changed. The networks have moved to frequencies that are harder to get through.

IBC systems have evolved through three broad architectures. Passive systems use a single high-power transmitter in the comms room with thick coaxial cabling branching out to simple antennas throughout the building. Hybrid systems place Coverage Nodes on each level, connected back to an Access Unit via fibre or ethernet, but still use coaxial runs to distribute antennas on each floor. Active systems (sometimes called Low-Power Active) place intelligent Coverage Nodes throughout the building, each with integrated antennas, connected back to an Access Unit over fibre or ethernet.

Most modern deployments use either a hybrid or active architecture. They support higher frequencies, advanced antenna techniques like MIMO, and costs less to install because fibre and ethernet are more affordable to run than heavy coaxial cable.

Passive systems however still have their place - harsh environments, simple building layouts, buildings with minimal users.

The good news is all three architectures are fully supported by Axidra, allowing our team to determine the right fit for your building and organisation.

A single-technology IBC boosts one service, typically one mobile operator's 4G-5G network. Multi-technology UBC systems can carry multiple operators, Private 5G, WiFi, LoRa, IoT, and in some cases public safety radio simultaneously through the same infrastructure. Many modern commercial deployments are multi-technology because buildings rarely have just one wireless need. A warehouse might require public mobile for staff, Private 5G for autonomous vehicles, and Bluetooth/LoRa for inventory sensors, all delivered through one system.

Axidra's systems range from a single repeater covering a small office or a single floor, through to multi-floor deployments with dozens of Coverage Nodes across a campus. The right system matches the building and the business. There's no minimum size that makes IBC "worth it."

While there is no strict maximum size, there is a natural maximum number of users/occupants before a Carrier-Led DAS is required.

The term DAS (Distributed Antenna System) comes up frequently in the mobile coverage space, and it can mean different things depending on context. Strictly speaking, DAS is an architecture, not a product. Most IBC systems use a DAS topology - a central unit distributing signal to antennas throughout the building.

In construction tenders and building contracts, the term "DAS" or "Third Party DAS" can refer to something more specific. It usually means an MCF (Mobile Carriers Forum) standards-compliant cabling and antenna system that the construction contractor is required to have designed and installed into the building. This gives the mobile network operators the opportunity to connect their equipment if they elect to do so. Once installed, each MNO is given the opportunity to connect to the DAS by installing a dedicated cellular base station in the DAS room. This is at the building owner's cost, with typical connection costs ranging anywhere from $100,000 to $300,000 depending on the building's requirements.

Carrier-led DAS in major venues (high-rise towers, stadiums, airports, major shopping centres) is a different proposition again. These are multi-million dollar deployments designed for high-capacity public spaces with thousands of simultaneous users, occasionally funded or co-funded by the carriers.

Most commercial and industrial buildings don't need carrier-led DAS and won't attract carrier funding. Independent IBC provides reliable coverage at a fraction of the cost, with the building owner retaining control over their connectivity rather than waiting on a carrier's priorities and timelines.

The nature of tender and construction documentation is that requirements can often be templated, leading to a lack of clarity around the types of systems permitted to be installed. We can help navigate and determine the right solution fit.

Axidra's platform is built for commercial operations: portfolio monitoring, multi-site management, enterprise reporting. We support simple repeater installations, including for enterprise clients who need to monitor many single-repeater sites across their portfolio. But if you're a homeowner looking for a residential solution, one of our installation partners who specialises in residential work would be best placed to help.

Sometimes the issue isn't signal strength but network capacity. Tourist areas, event precincts, or buildings near public gathering points may experience congestion at peak times even when signal bars look fine.

In these situations, we will need to perform a deeper dive into the issue before recommending a solution. We will look at alternative donor cell sites, different frequency combinations, and work with the Mobile Network Operators in connecting the IBC to a Small Cell to provide dedicated capacity.