Resolving 3G Spectrum Compliance Concerns Among Malaysian Operators

Synopsis

At present Malaysia is at 5G implementation and stabilisation phase but during Malaysia’s 3G maturity phase, spectrum boundaries between Maxis, Celcom, and Digi came under scrutiny when operators reported interference at the edges of their licensed bands. Each operator suspected that neighboring networks were exceeding their allocated bandwidths. A compliance investigation was conducted using a base station test set to validate emission performance and receiver sensitivity. The outcome demonstrated that all operators were compliant with regulatory limits and that the perceived interference was due to systemic factors in spectrum allocation and equipment limitations rather than operator fault.

Companies Involved

• Maxis Communications
• Celcom Axiata
• Digi Telecommunications

The Challenge

• Operators reported perceived interference at the intersection of adjacent frequency bands allocated to Maxis, Celcom, and Digi.
• Concerns arose that one or more operators were overshooting into neighboring spectrum.
• The issue became sensitive because customer experience was at stake and no operator wanted to be held responsible.
• The regulator required a neutral technical verification before mandating costly changes.

Key technical challenges included:

• Adjacent Channel Interference (ACI) – overlap at spectrum edges.
• Guard Band Limitations – allocations left little margin for error.
• Shared Infrastructure – co-located towers increased risk of intermodulation.
• Device Sensitivity – some 3G handsets had limited blocking capability.

The Solution

• A compliance report was commissioned by Maxis to investigate emissions and spectrum use across all three operators.
• Base Station Test Set was deployed to replicate real-world BTS signals in controlled conditions and measure:
• Out-of-band emissions (transmitter compliance).
• Blocking and selectivity (receiver performance).
• Multi-operator coexistence scenarios.
• The results were presented in a shared technical meeting with all operators, ensuring transparency and mutual validation.

The Results

• All three operators were found compliant with 3GPP and MCMC regulatory emission limits.
• The apparent interference was traced to a combination of tight spectrum allocations, shared site environments, and handset receiver limitations, not operator fault.
• The joint session defused tensions between operators and built a cooperative approach to spectrum management.
• Regulatory trust was reinforced, as the report showed transparency and fairness in compliance testing.
• No punitive measures were imposed; instead, operators collaborated on frequency planning, improved site engineering, and voluntary filter upgrades to minimize future overlap risks.