Frequency-hopping plan hits defence barricade
The defence ministry has raised a red flag against cognitive radios, the new technology that can alleviate spectrum scarcity. Use of this cutting-edge technology will make adversaries ‘completely aware’ of spectrum usage by defence services making secure networks vulnerable, the ministry said.
Defence ministry’s objection was sent to administrative telecom department that is finalising the new telecom policy and unified licensing regime that was discussed by the Cabinet at least on two occasions before it was cleared.
The ministry stated that with foreign direct investment (FDI) in telecom sector, foreign companies would have access to information on technical/transmission characteristics of emitters and knowledge about the defence services’ spectrum usage patterns. While Cabinet cleared the new telecom policy last week, telecom ministry has assured that cognitive radios will not be introduced without consulting the defence establishment.
Cognitive radios refer to the use of transmitters and receivers that continuously scan airwaves and shift communication to a frequency band where there is least activity.
Known for frequency-hopping, cognitive radios provides users with best call quality. Use of cognitive radios, it is believed, will alter the current mechanism of allocating spectrum to firms in specific slots. Multiple firms will be able to share the same slot and dynamically allocated spectrum would be used almost 20,000 times more efficiently.
Federal Communications Commission (FCC), the US counterpart of Trai, is also grappling with the issue of spectrum scarcity in the wake of an explosion in data usage.
It is actively considering newer ways of sharing spectrum including cognitive radios.
Cognitive radios are seen as having the potential to remove spectrum scarcity. Reserving spectrum to allow shifting of some telecom services firms to higher frequencies and reluctance of defence services to vacate spectrum have been opposed by relatively new players. They have cited the dwindling quality of services with increasing customer base as the reason for their opposition.
“This (cognitive radios) happens to be an active area of research for telecom companies that have to manage a huge network in terms of customer base and geographic spread with a very limited amount of spectrum,” said Hemant Joshi, partner and telecom leader at Deloitte, Haskins and Sells.
Apart from cognitive radios, low-earth communication and wireless fidelity (Wi-Fi) for last mile connectivity were also active areas of research. “Despite technology demonstration (cognitive radio), a mass-product is about ten years away,” felt Shankar Prakriya, a professor at Indian Institute of Technology in Delhi who researches cognitive radio systems (CRS).
He added that there was great interest from the Navy for inter-ship communication. The real challenge, he feels, is compatibility with existing standards for 2G and 3G. “CRS implementation is most likely for 4G, given that standards are still evolving,” he pointed out.
At present, telcos use a lot of power to beam signals into buildings. By letting Wi-Fi carry the signal inside the building, telcos can reduce their power requirements and offload spectrum. “These technologies are still some ways away,” said Rajat Mukarji, head of corporate affairs and strategy at Idea Cellular.