Mobile Networks and Spectrum

The one trade-off that explains every spectrum debate

Radio spectrum used for mobile networks is scarce, licensed, and auctioned, and almost every policy detail on this topic follows from a single physical trade-off: lower frequencies travel further and penetrate obstacles better; higher frequencies carry more data but travel a shorter distance and are blocked more easily.

This is why 5G networks are built from more than one frequency band at once rather than a single one. Sub-6 GHz spectrum gives wide coverage with moderate speed gains over 4G, useful for blanketing a city or a rural area with a manageable number of towers. mmWave spectrum (millimetre wave, above roughly 24 GHz) gives dramatically higher speeds but over a very short range, often just a few hundred metres, and is blocked by walls, so it is deployed densely in specific high-demand locations such as stadiums and city centres rather than as a general-purpose layer.

India's 2024 spectrum auction, and why it looked underwhelming

India's most recent spectrum auction, held over 25-26 June 2024, sold roughly 141 MHz of spectrum for about Rs 11,340 crore. Compared to the 2022 auction, which raised over Rs 1,50,000 crore, this looks like a dramatic decline, and it is worth understanding why rather than assuming it signals a problem with the sector.

No bidding took place at all in several bands, including 800 MHz, 2300 MHz, 3300 MHz and 26 GHz. The straightforward explanation is that operators had already acquired the spectrum they needed in the much larger 2022 auction to build out their initial 5G networks, so the 2024 round was a smaller, targeted top-up rather than a fresh buildout, and low demand in an auction is not automatically evidence of a weak telecom sector.

The 6 GHz band: contested between two futures

The 6 GHz band is a genuinely live policy dispute worth understanding rather than memorising as a fact. Of 1,200 MHz of spectrum available in this band, only 400 MHz, split into two separate chunks, is currently available for auction, with the remaining 300 MHz not available until 2030. The 6 GHz band matters because it is being pulled in two directions: telecom operators want it auctioned for licensed 5G and future 6G use, while Wi-Fi advocates want it left unlicensed, since unlicensed spectrum is what lets manufacturers build Wi-Fi routers and devices without needing an operator's licence at all. How this band is eventually allocated will shape whether India's next generation of high-speed wireless is delivered mainly through mobile operators or mainly through unlicensed Wi-Fi.

Looking past 5G: the Bharat 6G Vision

India has already set out its position for the generation after 5G. The Bharat 6G Vision document, released in March 2023, sets a goal of India becoming a frontline contributor to the design, development and deployment of 6G technology by 2030, built around the principles of affordability, sustainability and ubiquity. The Bharat 6G Alliance, bringing together industry, academia, research institutions and standards bodies, has grown to over 80 member organisations, including more than 30 startups, to carry that vision forward. The same 6 GHz band described above is expected to matter directly for 6G, since more of it is due to become available closer to the end of this decade.

Quick revision points

• The core trade-off: lower frequencies travel further and penetrate obstacles better; higher frequencies carry more data over a shorter range. This is why 5G combines multiple bands rather than using one.
• Sub-6 GHz: wide-area coverage, moderate speed gain over 4G. mmWave (above ~24 GHz): very high speed, very short range, blocked by walls, deployed densely in specific high-demand spots.
• 2024 spectrum auction (25-26 June): only ~141 MHz sold for ~Rs 11,340 crore, a sharp fall from 2022's Rs 1,50,000+ crore, because operators had already bought what they needed for their initial 5G rollout in 2022. Several bands saw zero bidding.
• 6 GHz band: only 400 MHz of 1,200 MHz currently available for auction, contested between telecom operators (want it licensed for 5G/6G) and Wi-Fi advocates (want it unlicensed).
• Bharat 6G Vision (March 2023): India aims to be a frontline 6G contributor by 2030, built on affordability, sustainability and ubiquity. Bharat 6G Alliance: 80+ member organisations, 30+ startups.