In a groundbreaking development, SpaceX’s Starlink has successfully established text messaging communication through its satellites.
This achievement comes merely six days after SpaceX’s launch of Starlink satellites equipped with direct-to-cell capabilities.
SpaceX’s latest feat involves the relay of text messages to and from unmodified smartphones on Earth, utilizing T-Mobile’s network spectrum.
While specific details about the test’s speeds and latency remain undisclosed, SpaceX reported that the launch and early tests of this technology proceeded without any complications.
One of the major hurdles SpaceX had to overcome was adapting consumer smartphones, typically equipped with “low gain antennas” designed for terrestrial cell tower connections, to communicate with satellites orbiting high above the Earth at approximately 340 miles.
To tackle this challenge, SpaceX has outfitted select Starlink satellites with custom silicon and advanced phased arrays, ensuring reliable communication with cell phones from space.
The same Starlink satellites boast the capability to employ 4G technology using an LTE modem onboard.
However, unlike stationary cell towers, these satellites orbit the Earth at a rapid pace of 17,000 miles per hour, making it challenging to maintain a steady signal to users on the ground.
SpaceX’s D2D efforts are currently led by Ben Longmier whose startup, Swarm Technologies, was acquired back in 2021.
SpaceX acknowledges the necessity of seamless handoffs between satellites and ground stations to mimic the functionality of traditional cell towers.
Achieving this requires careful consideration of satellite altitudes, beam size and placement, elevation angles, and the number of satellites.
The successful completion of handoffs is crucial due to the brief visibility of each Starlink satellite in the sky before orbiting out of view.
The Federal Communications Commission (FCC) has granted SpaceX approval to commence testing of the cellular Starlink system in over two dozen locations, utilizing 840 satellites set to launch in the coming months.
However, full FCC approval for commercial operation in the US is still pending, owing to concerns about potential radio interference.
In the interim, SpaceX also filed with the FCC to extend the testing period of its D2D efforts by another 30 days:
Looking ahead, SpaceX intends to expand testing to enhance coverage and plans to launch the cellular Starlink service specifically for T-Mobile customers later this year, starting with text messages.
Subsequently, the company aims to extend its services to include voice and data by 2025.
SpaceX’s achievement in space-based text messaging is a remarkable step toward its vision of providing global connectivity.
This accomplishment comes amid ongoing debates with regulatory bodies, including the FCC’s decision to deny SpaceX $885.5 million in rural broadband subsidies in December.
Despite regulatory challenges, SpaceX CEO Elon Musk envisions this technology as a means to enable mobile phone connectivity worldwide, particularly in areas with limited connectivity, though acknowledging potential competition with existing terrestrial cellular networks.