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Sorry for the naïve question, but shouldn't "cellphone towers in space" require phones to emit more powerful signal to reach the satellite than they do for terr

by forty 3y ago

Sorry for the naïve question, but shouldn't "cellphone towers in space" require phones to emit more powerful signal to reach the satellite than they do for terrestrial towers?

JumpCrisscross 3y ago
> shouldn't "cellphone towers in space" require phones to emit more powerful signal to reach the satellite than they do for terrestrial towers? Ceteris paribus, yes. In practice, beam forming and the lack of vertical compared with horizontal obstacles reduce the distance. I'm not finding ready information for 5G terrestrial towers versus Starlink.
kube-system 3y ago
Cellphones are UHF which follows a line-of-sight propagation pattern. It transmits much better through an empty sky than across the ground where there are obstacles. The Voyager spacecraft are billions of miles away and use 23 watt radios. The video streamed from the moon landing used a 20 watt radio to transmit a quarter-million miles. Starlink is just a couple hundred miles up.
- sbierwagen 3y ago
  >23 watt radio Transmitting from a 3.6 meter wide parabolic antenna, received by 70 meter wide parabolics, at a rate of 160 bits per second...
  - kube-system 3y ago
    And about 30 million times the distance.
    - lostmsu 3y ago
      Which is just under 1 000 000 000 000 000 times more signal strength loss assuming quadratic dispersion.
hmottestad 3y ago
When last I heard about it the bandwidth was going to be in the kbps ballpark.
deleted 3y ago
[deleted]
ianburrell 3y ago
These Starlink satellites have a large antenna to pick up cell signals. The antenna is a big part of the difference between V1 and V2 satellites. Also, the bandwidth is pretty low. It tops out at 18Mbps per cell, but that is divided across all the users in the cell. Each person will get 100kbps. Starlink is going to start with texting and add voice and data in 2025. They haven't indicated how fast data will I'm guessing 2G speeds. The service will basically be 2G, text, voice, and some data, everywhere.

by forty 3y ago

Sorry for the naïve question, but shouldn't "cellphone towers in space" require phones to emit more powerful signal to reach the satellite than they do for terrestrial towers?

JumpCrisscross 3y ago

> shouldn't "cellphone towers in space" require phones to emit more powerful signal to reach the satellite than they do for terrestrial towers? Ceteris paribus, yes. In practice, beam forming and the lack of vertical compared with horizontal obstacles reduce the distance. I'm not finding ready information for 5G terrestrial towers versus Starlink.

kube-system 3y ago

Cellphones are UHF which follows a line-of-sight propagation pattern. It transmits much better through an empty sky than across the ground where there are obstacles. The Voyager spacecraft are billions of miles away and use 23 watt radios. The video streamed from the moon landing used a 20 watt radio to transmit a quarter-million miles. Starlink is just a couple hundred miles up.

sbierwagen 3y ago
>23 watt radio Transmitting from a 3.6 meter wide parabolic antenna, received by 70 meter wide parabolics, at a rate of 160 bits per second...
- kube-system 3y ago
  And about 30 million times the distance.
  - lostmsu 3y ago
    Which is just under 1 000 000 000 000 000 times more signal strength loss assuming quadratic dispersion.

hmottestad 3y ago

When last I heard about it the bandwidth was going to be in the kbps ballpark.

deleted 3y ago

[deleted]

ianburrell 3y ago

These Starlink satellites have a large antenna to pick up cell signals. The antenna is a big part of the difference between V1 and V2 satellites. Also, the bandwidth is pretty low. It tops out at 18Mbps per cell, but that is divided across all the users in the cell. Each person will get 100kbps. Starlink is going to start with texting and add voice and data in 2025. They haven't indicated how fast data will I'm guessing 2G speeds. The service will basically be 2G, text, voice, and some data, everywhere.