How iBUS Achieved 99% Call Success Inside a 100-Year-Old Government Landmark

The Bihar Vidhan Sabha, a 100-year-old heritage legislative building housing VIP offices, staff chambers, and underground conference halls, had long struggled with mobile signal blackouts that left staff dependent on landlines and intercoms. With no structural modifications permitted and no cable route documentation available, iBUS Networks engineered a hybrid, fibre-fed Distributed Antenna System (DAS) — a network of indoor antennas and small cells that rebroadcasts signal from every major telecom operator throughout the building. The result: a 99% call setup success rate, dropped calls under 0.5%, and zero signal escalations from government authorities, all delivered without a single drill hole in a protected heritage structure.

At a Glance

The Challenge

The Bihar Vidhan Sabha is one of India's most prominent legislative buildings, but this century-old heritage structure had long struggled with severe mobile signal blackouts. Coverage was especially poor across underground conference halls and VIP offices, including the Speaker's and Chief Minister's chambers. Staff were heavily reliant on landlines and intercoms, often unable to send or receive documents via mobile at all.

• No structural modifications permitted: as a protected heritage building, drilling or invasive cabling was off the table entirely.
• No cable route documentation: no accessible blueprints existed, so routing had to be worked out manually, room by room.
• Network blackouts in high-stakes areas: VIP offices and underground halls, used during assembly sessions and official visits, had little to no usable signal.
• No usable donor signal: thick heritage walls blocked incoming outdoor signal before it could reach the antenna system.
• Restricted access windows: installation could not take place during active assembly sessions, narrowing the available working hours considerably.

The Solution

iBUS Networks designed a hybrid, fibre-fed DAS combined with small cells for high-traffic zones such as VIP offices, halls, and staircases, built to integrate with every major telecom operator under a single, shared neutral-host model. The system was engineered specifically around the building's heritage constraints: multi-band coverage (700, 1800, 2100, and 2600 MHz) for both LTE and 5G, fed through a baseband unit for clean signal sourcing, with all cabling routed on the surface rather than through walls or floors.

How It Was Built

• Site survey and planning: A full manual walkthrough identified signal-dead zones, with RF data recorded using tools like iBwave and Atoll, and floor-wise cable routing documented by hand in the absence of blueprints.
• Technology and stakeholder coordination: iBUS coordinated directly with BSNL, Airtel, and other operators, securing every permission from Vidhan Sabha authorities before a neutral-host model was approved and implemented.
• Infrastructure deployment: 300+ indoor antennas and 17 Remote Radio Units were installed, with small cells placed in lobbies and critical chambers, and a central hub established in the building's technical room — all surface-mounted, with zero structural impact.
• Optimization and testing: Walk tests and drive tests using TEMS and NEMO fine-tuned signal strength through antenna gain, tilt, and orientation, benchmarked against pre- and post-deployment signal and call-quality data.
• Monitoring and handover: Real-time dashboards were deployed for ongoing monitoring, the system was integrated with operator base stations, and the facility management team was trained on fault alerts and escalation.
• Walk tests and drive tests were done using TEMS and NEMO; RF modeling and link budget analysis via iBwave and Atoll.

Results: Before and After

Technical Outcomes

• 300+ indoor antennas and 17 Remote Radio Units installed across VIP offices, halls, and underground chambers.
• Signal strength consistently above RSRP -90 dBm and SINR 10 dB across all underground, stairwell, and office zones.
• Indoor data speeds consistently above 100 Mbps, with seamless handovers and zero session interruption.
• Entire deployment completed with zero drilling or invasive cabling inside a protected heritage structure.
• Multi-band, LTE and 5G-ready architecture built for long-term scalability across four frequency bands.

Institutional Impact

• Uninterrupted Legislative Operations: Reliable coverage was delivered without disrupting assembly sessions, with all sensitive installation work scheduled around restricted access windows.
• Government Confidence: Zero escalations from government authorities since deployment reflects a level of reliability expected in a high-security legislative environment.
• Heritage Preservation: The entire network was delivered without a single drill hole or structural change, fully preserving a century-old protected building.
• Future-Ready Infrastructure: Multi-band design across 700–2600 MHz ensures the building is ready for both current LTE demand and next-generation 5G rollout.

Updating Generations

Before this deployment, staff inside the Vidhan Sabha couldn't send or receive documents on their phones, having to rely on landlines and intercoms to get basic work done inside their offices. This gap mattered most in the moments they could least afford it - during VIP visits and live assembly sessions. Today, staff communicate freely via mobile, officials use apps and digital documentation is done without restriction. Routine transactions like canteen payments have shifted to mobile. Now inside this old landmark reliable signal isn't a convenience, it's what lets a working government building function like a modern one.