Government ministries in India are questioning Project Loon on grounds of signal interference. The specific issue is that Project Loon proposes to use the 700-MHz to 900-MHz spectrum for uplink and downlink, spectrum that in India is allocated for mobile use.

A concern about potential surveillance is a concern of the Indian Defense ministry, but most believe that can be resolved if the chief obstacle, the objection by the Indian Department of Telecommunications about signal interference,  is addressed.

This is not the sort of issue Project Loon would have missed anticipating, especially since Project Loon presently views itself as a backhaul technology working with retail mobile service providers.

The somewhat obvious work-around solutions might be modeled on other similar ways common spectrum can be used without interference problems. Chief among those ways is the use of point-to-point links between stationary ground stations and the balloons.

In much the same way that point-to-point optical links do not interfere with each other so long as their paths do not cross, it should be possible to engineer very precise point-to-point radio links that use the same technique to avoid interference with higher-power ground-based radios.

Skeptics, including service providers or transport providers whose business interests might face new competition, have asked general questions about the feasibility of Google’s Project Loon almost from the start.

Some of the issues are similar to questions raised about use of unmanned aerial drones that Facebook and Google both are working on as well. The issue is the use of specific downlink (and uplink) frequencies.

“Where will Project Loon get rights to use such frequencies?” some have asked. There is no universal long-term answer, yet, as Project Loon remains in testing phase, though Sri Lanka might move to commercialize sooner than most other countries. Sri Lanka officials already have committed to commercial service at some point in the future.

 

In Indonesia, for example, the big mobile companies are partnering with Project Loon for a test of the service, and that is not something they would have done if it was believed there is no way to avoid interference.

In 2016, the top three mobile network operators in Indonesia–Indosat, Telkomsel, and XL Axiata–will test Project Loon, a constellation of balloons to deliver Long Term Evolution 4G signals across the country.

Sri Lanka might be going further, and reportedly is planning on relying on Project Loon to cover the island for Internet access, starting as early as March 2016. There would seem to be some significant issues to be settled, if that timetable is to be kept.

Unless something new has been developed, Project Loon would beam signals to stationary antennas, much as a fixed wireless network would do. There would be no way to deliver signals directly to a mobile phone using LTE, for example.

Who gets to use spectrum, and concerns about interference from other users, always are relevant problems for wireless communications providers. That now appears to be an issue for Google’s Project Loon in India.