SpaceX is hoping to test its cellular Starlink system as soon as next month through 840 satellites, according to an FCC filing.

The company filed the application for the experimental license this week as the FCC continues to mull whether to give SpaceX full authorization to operate the satellite-to-cellular communication service amid concerns about interference.

According to the filing, SpaceX is requesting “special temporary authority” to conduct the test starting on Dec. 10 through a period lasting 180 days. The goal is to test out the system in partnership with T-Mobile using the carrier’s licensed radio spectrum to beam the satellite connectivity to 2,000 test devices.

"Over the 180-day experimental STA period, SpaceX expects to operate approximately 840 satellites with direct-to-cellular payloads," the company wrote, suggesting it's quickly building up the capacity to launch the cellular Starlink system.

“At any given time, approximately 60 of these 840 (satellite) payloads will be serving handsets in the United States under this experimental authorization,” the application adds. SpaceX will beam the satellite connectivity to 13 areas across the US, including Mountain View, California; Kansas City, Kansas; and Houston, Texas.

It’s not the first time SpaceX has filed an application to conduct a test via the proposed cellular Starlink system. In October, the company also made a separate filing to conduct a similar test over a 60-day period starting in December. But the application faced resistance from AT&T and the Rural Wireless Association, with both arguing SpaceX should have made the request to the FCC’s Office of Engineering and Technology through an experimental license.

The new application from SpaceX does just that. The company is targeting a launch of the cellular Starlink service for next year with the goal of operating the technology over a total of 7,500 satellites. But concerns about the satellites generating radio interference with other carriers and satellite companies seems to be delaying SpaceX from receiving FCC clearance.

SpaceX already told the FCC that the cellular Starlink system poses no radio signal threat. Still, its new application notes it’ll be able to run a variety of real-world tests to check whether the cellular Starlink technology actually risks causing interference. This will include measuring the signal strength from the Starlink satellites and the T-Mobile handsets on the ground.

“SpaceX certifies that its direct-to-cellular system will operate without causing harmful interference to or requiring protection from any other service duly licensed in these bands or adjacent bands,” the company added. If interference does occur, then both SpaceX and T-Mobile plan on taking “all reasonable steps” to eliminate the problem.

The company goes on to urge the FCC to approve the application. “These tests will enable SpaceX to more quickly realize the consumer benefits of its direct-to-cell technology without causing harmful interference to other licensed operators."