this week, A company called AST SpaceMobile announced The company said it had successfully used AT&T’s cellular network to transmit a 4G LTE signal from a BlueWalker 3 satellite to an “off-the-shelf smartphone” in Hawaii. According to the press release, it “repeatedly achieved download speeds in excess of 10 Mbps during testing.” Fast enough for normal browsing, messaging, and even watching videos.
What’s striking here is that mobile phones usually connect to terrestrial base stations rather than satellites. That’s why it’s hard to get cell phone service when you’re on a boat miles away from the ocean or traveling in the countryside. But by using satellites, AST SpaceMobile could theoretically extend its coverage to almost anywhere on Earth. No more worrying about passing through signal dead zones.
“AST SpaceMobile’s space-based cellular capabilities are designed to be a significant extension of cellular communications,” said Abel Abelan, Chairman and CEO of AST SpaceMobile, in a press release. . “In addition to the basic voice and text support you’d expect from a phone, users can now browse the internet, download files, use messaging apps and stream videos. increase.”
One of the big problems with cell phone coverage is that cell phone towers surprisingly limited range. Consider the 5G networking standard. It relies on three different spectrum bands to provide three different types of cellular service. Low-band 5G uses frequencies below 1 GHz and has the greatest range but the lowest speed (Maximum speed is around 100 Mbps); the mid-band uses frequencies from 1 GHz to 6 GHz and offers a great balance between speed and range. Highband or millimeter wave (mmWave) uses frequencies from 24 GHz to 40 GHz and allows speeds of Gbps, but only within a few hundred feet. In other words, speed decreases as range increases.
In urban and suburban areas, you are usually within a mile or two of a cell tower that provides telephone service.In rural areas, towers are theoretically Range up to 45 milesHowever, the range is often much shorter, as connections are affected by the wavelengths the towers transmit, the geography of the area, the strength of the signal transmitted, and many other factors.
This means that delivering high-speed cellular broadband to a large area like the United States using ground-based towers is a major challenge that cannot be easily solved with existing technology. This is where the idea of space-based broadband comes into play.
There are also satellite phones. iridiumand satellite broadband services that require small plates, etc. star link, there is still no satellite broadband service that can reach regular smartphones. This will allow mobile operators to offer comprehensive service throughout the country. And this is the service AST SpaceMobile is trying to build.
“Our successful satellite-to-smartphone test reached double-digit download speeds, helping people across the United States stay connected regardless of their location,” said Chris Sambar, head of AT&T, in a press release. We are one step closer to making it possible.” ”
Deploying this kind of technology will connect your smartphone to cell towers on the ground most of the time, but when you’re driving through the Sierra Nevada or Rocky Mountains, you’ll be able to connect to satellites in the lowlands. . trajectory. Apparently, AST SpaceMobile already has “agreement and understanding” he has with more than 35 global mobile phone providers.
For its latest success, AST SpaceMobile relied on the BlueWalker 3 satellite. According to the company, the satellite is “the largest commercial communications array ever deployed in low-Earth orbit.” It is now fully deployed and covers 693 square feet. I was able to send his 4G LTE signal to a cell phone in Hawaii through AT&T’s network. Next, the company hopes he will achieve 5G speeds.
Of course, satellite broadband has its own problems. There are concerns that we are already sending too many satellites into space. Space-based communications are effective for downloading files and making and receiving phone calls. upload speed Latency (the time it takes for data to be sent from the smartphone to the server and receive a response) can be taken into account. Much lower than what you get from a tower above ground. Even if the satellite is in low earth orbit, the round trip to space can take a long time.
Still, whether you’re excited or terrified that one day you’ll be able to drive across America without losing your cell phone signal, this latest news may bring us closer to it. suggests not.
