Connectivity to get better at airports, DoT looking to resolve 5G coverage issues within a month

5G Airport

The Department of Telecommunications (DoT) expects to improve 5G connectivity at and around 124 airports in the country and is currently running tests with the space and technology department to ensure that the service doesn't interfere with aircraft systems, sources told Moneycontrol.

If all goes to plan, not just flyers but people living near airports, too, will gain access to 5G services by the end of September. The 3,300-3,670 MHz band frequency, the band in which 5G services operate in India, is prohibited near airports due to concerns about potential interference with aircraft radio altimeters, which calculate the height of a plane above ground and also help in air traffic management.

"We are testing with the DST (Department of Science and Technology), and we will be able to figure something out within a month. It is one of the priorities," a senior government source said.

The telecom department is also working with the civil aviation ministry to improve 5G connectivity and recently allowed the deployment of in-building (IBS) solutions to improve coverage in and around airports, the source said.

In-building are systems and technologies designed to provide high-quality mobile and wireless communication indoors where signal penetration from cell towers can be weak.

In November 2022, the DoT instructed telecom operators to refrain from setting up 5G sites in the 3,300-3,670 MHz band within 2.1 km of both runway ends.

Airport connection

Indian telcos which have commercially rolled out 5G services argue that the decision to not allow the fifth-generation technology around airports is causing revenue loss.

They have made huge investments in purchasing the 5G spectrum and the lack of connectivity at airports deprives them of an opportunity to generate revenue from consumers as well as businesses, they have argued.

The existing altimeters operate in the 4,200-4,400 MHz band, approximately 500 MHz away from 5G frequencies. Concerns about possible interference caused by radio altimeters' poor out-of-band reception characteristics have been raised.

In June, the Global System for Mobile Communications A (GSMA), which represents telecom service providers worldwide, wrote to DoT to reconsider its 2022 decision and allow telcos to expand mobile networks across airports.

The country's 5G assignments in the 3.5 GHz band already included a 530 MHz guard band between mobile systems and radio altimeters, larger than in many other countries, it said.

"We urge the DoT to take necessary steps with the stakeholders in the aviation sector for expediting replacement of radio altimeters in a specific timeframe that is eventually identified as potentially susceptible to emissions outside their band (and, in particular, to emissions in the "5G" band), to allow harmonious coexistence between the different services and technologies that use the radio spectrum," GSMA said in its June.

The issue first arose when the US Federal Aviation Administration warned in January 2022 that 5G signals in the C-spectrum band (3,300-4,200 MHz) could interfere with aircraft altimeter systems operating in the nearby 4,200-4,400 MHz range.

India's scenario differs from the US, where the operating range of 5G systems extends to 3,980 MHz. The spectral separation between the 5G systems and radio altimeters in the US is only 220 MHz. In India, it is 530 MHz, almost 2x more than in the US, GSMA said.

A guard band is a narrow frequency that separates two broader frequency ranges to prevent interference between them.

Out of nearly 300 operators launching 5G services by the end of Q1 2024, 186 operators (including FWA launches) deployed their next-generation networks using the 3.5 GHz frequency range. There have been "no reported cases of interference" arising from 5G networks, GSMA said.