Pictures from Mars
$begingroup$
How is it that NASA receives broadcasts from 300 million miles away but Sprint needs to install transmitters every 500ft for 5G wireless?
mars communication rovers interplanetary
asked 17 hours ago
Jay DohJay Doh
423
New contributor
Jay Doh is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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$endgroup$
add a comment |
$begingroup$
How is it that NASA receives broadcasts from 300 million miles away but Sprint needs to install transmitters every 500ft for 5G wireless?
mars communication rovers interplanetary
asked 17 hours ago
Jay DohJay Doh
423
New contributor
Jay Doh is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
4
$begingroup$
Have you compared the transmission bandwidths/speeds and the energy used in both cases?
$endgroup$
– DarkDust
17 hours ago
5
$begingroup$
You could talk to deep space too if you put a 20 kilowatt battery in your cell phone and sat at the focus of this parabola, and still were willing to put up with text messages at one letter per second ;-) planetary.org/blogs/emily-lakdawalla/2011/3253.html The trick to deep space communication lies in a combination of having a large dish at one or both ends of the connection and using one or both high power and low data rates compared to cell phones.
$endgroup$
– uhoh
16 hours ago
$begingroup$
5G differs from 4G in granularity by beam-forming and directing different signals preferentially to different individual users; the architecture requires a higher density and smaller spacing, with lower power per user. Actually answer to Could “live” video be transmitted from Mars? show that video is possible from Mars with current-level technology, but it's not easy.
$endgroup$
– uhoh
16 hours ago
$begingroup$
Related Can I text on my cell phone from the ISS to Earth?
$endgroup$
– James Jenkins
13 hours ago
add a comment |
$begingroup$
How is it that NASA receives broadcasts from 300 million miles away but Sprint needs to install transmitters every 500ft for 5G wireless?
mars communication rovers interplanetary
asked 17 hours ago
Jay DohJay Doh
423
New contributor
Jay Doh is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
How is it that NASA receives broadcasts from 300 million miles away but Sprint needs to install transmitters every 500ft for 5G wireless?
mars communication rovers interplanetary
mars communication rovers interplanetary
asked 17 hours ago
Jay DohJay Doh
423
New contributor
Jay Doh is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 17 hours ago
Jay DohJay Doh
423
New contributor
Jay Doh is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 17 hours ago
Jay DohJay Doh
423
New contributor
Jay Doh is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 17 hours ago
Jay DohJay Doh
423
asked 17 hours ago
Jay DohJay Doh
423
423
New contributor
Jay Doh is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Jay Doh is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Jay Doh is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
4
$begingroup$
Have you compared the transmission bandwidths/speeds and the energy used in both cases?
$endgroup$
– DarkDust
17 hours ago
5
$begingroup$
You could talk to deep space too if you put a 20 kilowatt battery in your cell phone and sat at the focus of this parabola, and still were willing to put up with text messages at one letter per second ;-) planetary.org/blogs/emily-lakdawalla/2011/3253.html The trick to deep space communication lies in a combination of having a large dish at one or both ends of the connection and using one or both high power and low data rates compared to cell phones.
$endgroup$
– uhoh
16 hours ago
$begingroup$
5G differs from 4G in granularity by beam-forming and directing different signals preferentially to different individual users; the architecture requires a higher density and smaller spacing, with lower power per user. Actually answer to Could “live” video be transmitted from Mars? show that video is possible from Mars with current-level technology, but it's not easy.
$endgroup$
– uhoh
16 hours ago
$begingroup$
Related Can I text on my cell phone from the ISS to Earth?
$endgroup$
– James Jenkins
13 hours ago
add a comment |
4
$begingroup$
Have you compared the transmission bandwidths/speeds and the energy used in both cases?
$endgroup$
– DarkDust
17 hours ago
5
$begingroup$
You could talk to deep space too if you put a 20 kilowatt battery in your cell phone and sat at the focus of this parabola, and still were willing to put up with text messages at one letter per second ;-) planetary.org/blogs/emily-lakdawalla/2011/3253.html The trick to deep space communication lies in a combination of having a large dish at one or both ends of the connection and using one or both high power and low data rates compared to cell phones.
$endgroup$
– uhoh
16 hours ago
$begingroup$
5G differs from 4G in granularity by beam-forming and directing different signals preferentially to different individual users; the architecture requires a higher density and smaller spacing, with lower power per user. Actually answer to Could “live” video be transmitted from Mars? show that video is possible from Mars with current-level technology, but it's not easy.
$endgroup$
– uhoh
16 hours ago
$begingroup$
Related Can I text on my cell phone from the ISS to Earth?
$endgroup$
– James Jenkins
13 hours ago
4
4
$begingroup$
Have you compared the transmission bandwidths/speeds and the energy used in both cases?
$endgroup$
– DarkDust
17 hours ago
$begingroup$
Have you compared the transmission bandwidths/speeds and the energy used in both cases?
$endgroup$
– DarkDust
17 hours ago
5
5
$begingroup$
You could talk to deep space too if you put a 20 kilowatt battery in your cell phone and sat at the focus of this parabola, and still were willing to put up with text messages at one letter per second ;-) planetary.org/blogs/emily-lakdawalla/2011/3253.html The trick to deep space communication lies in a combination of having a large dish at one or both ends of the connection and using one or both high power and low data rates compared to cell phones.
$endgroup$
– uhoh
16 hours ago
$begingroup$
You could talk to deep space too if you put a 20 kilowatt battery in your cell phone and sat at the focus of this parabola, and still were willing to put up with text messages at one letter per second ;-) planetary.org/blogs/emily-lakdawalla/2011/3253.html The trick to deep space communication lies in a combination of having a large dish at one or both ends of the connection and using one or both high power and low data rates compared to cell phones.
$endgroup$
– uhoh
16 hours ago
$begingroup$
5G differs from 4G in granularity by beam-forming and directing different signals preferentially to different individual users; the architecture requires a higher density and smaller spacing, with lower power per user. Actually answer to Could “live” video be transmitted from Mars? show that video is possible from Mars with current-level technology, but it's not easy.
$endgroup$
– uhoh
16 hours ago
$begingroup$
5G differs from 4G in granularity by beam-forming and directing different signals preferentially to different individual users; the architecture requires a higher density and smaller spacing, with lower power per user. Actually answer to Could “live” video be transmitted from Mars? show that video is possible from Mars with current-level technology, but it's not easy.
$endgroup$
– uhoh
16 hours ago
$begingroup$
Related Can I text on my cell phone from the ISS to Earth?
$endgroup$
– James Jenkins
13 hours ago
$begingroup$
Related Can I text on my cell phone from the ISS to Earth?
$endgroup$
– James Jenkins
13 hours ago
add a comment |
2 Answers
2
active
oldest
votes
$begingroup$
Let's compare with 4G, for which I could find some numbers:
Your cell phone is transmitting with speeds of up to 50MBps with a maximum of 1 Watt (can be as low as a few µW!), using a tiny antenna that is often obscured by water bags (human flesh and organs), rocks, buildings, trees, etc.
Let's compare this with Mars Express, for example: its maximum bandwidth back to earth is "just" 230kBps (AFAIK in the same order of magnitude as EDGE) at 5 Watt (S-Band) or 65 Watt (X-Band) using a large 1.6 Meter parabolic antenna. Its signal is received by huge and very expensive antenna dishes here on earth.
So these are very different systems with very different requirements. We don't want to transmit with too much power from our cell phones, yet also want to transmit with high speeds through various obstacles. This requires receivers in closer proximity than with lower speeds and/or higher energy.
answered 15 hours ago
DarkDustDarkDust
7,66433057
$endgroup$
$begingroup$
In addition, the space between the spacecraft and the Earth is vacuum for the most part.
$endgroup$
– mgarciaisaia
6 hours ago
2
$begingroup$
@mgarciaisaia, the space between your cell phone and the tower is also vacuum for the most part, at least as far as radio waves are concerned.
$endgroup$
– Mark
2 hours ago
add a comment |
$begingroup$
In addition to DarkDust's answer:
In radio, each two-way radio link needs its own channel, to avoid interference with other links. There is a limited number of channels available (don't know for 5G specifically, but Wifi only has 3 channels that don't interfere with each other).
So in order to support millions of simultaneous radio links, you need to reuse those channels. You can do that by reducing the range of each transmission: if a user on channel 1 only broadcasts in a 1-km radius, another user 2 km away can use channel 1 without interfering with the first user. Reduction in power also means the battery in your cell phone lasts much longer.
This is why Sprint installs so many transmitters.
For the Mars link, NASA uses a dedicated dish antenna 34 m in diameter, and a high-powered transmitter. It also supports communications with just one spacecraft at a time, so there's no need to share the radio link.
answered 15 hours ago
HobbesHobbes
91.3k2256409
$endgroup$
2
$begingroup$
+15G (specified in the question) also uses MIMO and Beamforming
$endgroup$
– uhoh
13 hours ago
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
Let's compare with 4G, for which I could find some numbers:
Your cell phone is transmitting with speeds of up to 50MBps with a maximum of 1 Watt (can be as low as a few µW!), using a tiny antenna that is often obscured by water bags (human flesh and organs), rocks, buildings, trees, etc.
Let's compare this with Mars Express, for example: its maximum bandwidth back to earth is "just" 230kBps (AFAIK in the same order of magnitude as EDGE) at 5 Watt (S-Band) or 65 Watt (X-Band) using a large 1.6 Meter parabolic antenna. Its signal is received by huge and very expensive antenna dishes here on earth.
So these are very different systems with very different requirements. We don't want to transmit with too much power from our cell phones, yet also want to transmit with high speeds through various obstacles. This requires receivers in closer proximity than with lower speeds and/or higher energy.
answered 15 hours ago
DarkDustDarkDust
7,66433057
$endgroup$
$begingroup$
In addition, the space between the spacecraft and the Earth is vacuum for the most part.
$endgroup$
– mgarciaisaia
6 hours ago
2
$begingroup$
@mgarciaisaia, the space between your cell phone and the tower is also vacuum for the most part, at least as far as radio waves are concerned.
$endgroup$
– Mark
2 hours ago
add a comment |
$begingroup$
Let's compare with 4G, for which I could find some numbers:
Your cell phone is transmitting with speeds of up to 50MBps with a maximum of 1 Watt (can be as low as a few µW!), using a tiny antenna that is often obscured by water bags (human flesh and organs), rocks, buildings, trees, etc.
Let's compare this with Mars Express, for example: its maximum bandwidth back to earth is "just" 230kBps (AFAIK in the same order of magnitude as EDGE) at 5 Watt (S-Band) or 65 Watt (X-Band) using a large 1.6 Meter parabolic antenna. Its signal is received by huge and very expensive antenna dishes here on earth.
So these are very different systems with very different requirements. We don't want to transmit with too much power from our cell phones, yet also want to transmit with high speeds through various obstacles. This requires receivers in closer proximity than with lower speeds and/or higher energy.
answered 15 hours ago
DarkDustDarkDust
7,66433057
$endgroup$
$begingroup$
In addition, the space between the spacecraft and the Earth is vacuum for the most part.
$endgroup$
– mgarciaisaia
6 hours ago
2
$begingroup$
@mgarciaisaia, the space between your cell phone and the tower is also vacuum for the most part, at least as far as radio waves are concerned.
$endgroup$
– Mark
2 hours ago
add a comment |
$begingroup$
Let's compare with 4G, for which I could find some numbers:
Your cell phone is transmitting with speeds of up to 50MBps with a maximum of 1 Watt (can be as low as a few µW!), using a tiny antenna that is often obscured by water bags (human flesh and organs), rocks, buildings, trees, etc.
Let's compare this with Mars Express, for example: its maximum bandwidth back to earth is "just" 230kBps (AFAIK in the same order of magnitude as EDGE) at 5 Watt (S-Band) or 65 Watt (X-Band) using a large 1.6 Meter parabolic antenna. Its signal is received by huge and very expensive antenna dishes here on earth.
So these are very different systems with very different requirements. We don't want to transmit with too much power from our cell phones, yet also want to transmit with high speeds through various obstacles. This requires receivers in closer proximity than with lower speeds and/or higher energy.
answered 15 hours ago
DarkDustDarkDust
7,66433057
$endgroup$
Let's compare with 4G, for which I could find some numbers:
Your cell phone is transmitting with speeds of up to 50MBps with a maximum of 1 Watt (can be as low as a few µW!), using a tiny antenna that is often obscured by water bags (human flesh and organs), rocks, buildings, trees, etc.
Let's compare this with Mars Express, for example: its maximum bandwidth back to earth is "just" 230kBps (AFAIK in the same order of magnitude as EDGE) at 5 Watt (S-Band) or 65 Watt (X-Band) using a large 1.6 Meter parabolic antenna. Its signal is received by huge and very expensive antenna dishes here on earth.
So these are very different systems with very different requirements. We don't want to transmit with too much power from our cell phones, yet also want to transmit with high speeds through various obstacles. This requires receivers in closer proximity than with lower speeds and/or higher energy.
answered 15 hours ago
DarkDustDarkDust
7,66433057
answered 15 hours ago
DarkDustDarkDust
7,66433057
answered 15 hours ago
DarkDustDarkDust
7,66433057
answered 15 hours ago
DarkDustDarkDust
7,66433057
7,66433057
$begingroup$
In addition, the space between the spacecraft and the Earth is vacuum for the most part.
$endgroup$
– mgarciaisaia
6 hours ago
2
$begingroup$
@mgarciaisaia, the space between your cell phone and the tower is also vacuum for the most part, at least as far as radio waves are concerned.
$endgroup$
– Mark
2 hours ago
add a comment |
$begingroup$
In addition, the space between the spacecraft and the Earth is vacuum for the most part.
$endgroup$
– mgarciaisaia
6 hours ago
2
$begingroup$
@mgarciaisaia, the space between your cell phone and the tower is also vacuum for the most part, at least as far as radio waves are concerned.
$endgroup$
– Mark
2 hours ago
$begingroup$
In addition, the space between the spacecraft and the Earth is vacuum for the most part.
$endgroup$
– mgarciaisaia
6 hours ago
$begingroup$
In addition, the space between the spacecraft and the Earth is vacuum for the most part.
$endgroup$
– mgarciaisaia
6 hours ago
2
2
$begingroup$
@mgarciaisaia, the space between your cell phone and the tower is also vacuum for the most part, at least as far as radio waves are concerned.
$endgroup$
– Mark
2 hours ago
$begingroup$
@mgarciaisaia, the space between your cell phone and the tower is also vacuum for the most part, at least as far as radio waves are concerned.
$endgroup$
– Mark
2 hours ago
add a comment |
$begingroup$
In addition to DarkDust's answer:
In radio, each two-way radio link needs its own channel, to avoid interference with other links. There is a limited number of channels available (don't know for 5G specifically, but Wifi only has 3 channels that don't interfere with each other).
So in order to support millions of simultaneous radio links, you need to reuse those channels. You can do that by reducing the range of each transmission: if a user on channel 1 only broadcasts in a 1-km radius, another user 2 km away can use channel 1 without interfering with the first user. Reduction in power also means the battery in your cell phone lasts much longer.
This is why Sprint installs so many transmitters.
For the Mars link, NASA uses a dedicated dish antenna 34 m in diameter, and a high-powered transmitter. It also supports communications with just one spacecraft at a time, so there's no need to share the radio link.
answered 15 hours ago
HobbesHobbes
91.3k2256409
$endgroup$
2
$begingroup$
+15G (specified in the question) also uses MIMO and Beamforming
$endgroup$
– uhoh
13 hours ago
add a comment |
$begingroup$
In addition to DarkDust's answer:
In radio, each two-way radio link needs its own channel, to avoid interference with other links. There is a limited number of channels available (don't know for 5G specifically, but Wifi only has 3 channels that don't interfere with each other).
So in order to support millions of simultaneous radio links, you need to reuse those channels. You can do that by reducing the range of each transmission: if a user on channel 1 only broadcasts in a 1-km radius, another user 2 km away can use channel 1 without interfering with the first user. Reduction in power also means the battery in your cell phone lasts much longer.
This is why Sprint installs so many transmitters.
For the Mars link, NASA uses a dedicated dish antenna 34 m in diameter, and a high-powered transmitter. It also supports communications with just one spacecraft at a time, so there's no need to share the radio link.
answered 15 hours ago
HobbesHobbes
91.3k2256409
$endgroup$
2
$begingroup$
+15G (specified in the question) also uses MIMO and Beamforming
$endgroup$
– uhoh
13 hours ago
add a comment |
$begingroup$
In addition to DarkDust's answer:
In radio, each two-way radio link needs its own channel, to avoid interference with other links. There is a limited number of channels available (don't know for 5G specifically, but Wifi only has 3 channels that don't interfere with each other).
So in order to support millions of simultaneous radio links, you need to reuse those channels. You can do that by reducing the range of each transmission: if a user on channel 1 only broadcasts in a 1-km radius, another user 2 km away can use channel 1 without interfering with the first user. Reduction in power also means the battery in your cell phone lasts much longer.
This is why Sprint installs so many transmitters.
For the Mars link, NASA uses a dedicated dish antenna 34 m in diameter, and a high-powered transmitter. It also supports communications with just one spacecraft at a time, so there's no need to share the radio link.
answered 15 hours ago
HobbesHobbes
91.3k2256409
$endgroup$
In addition to DarkDust's answer:
In radio, each two-way radio link needs its own channel, to avoid interference with other links. There is a limited number of channels available (don't know for 5G specifically, but Wifi only has 3 channels that don't interfere with each other).
So in order to support millions of simultaneous radio links, you need to reuse those channels. You can do that by reducing the range of each transmission: if a user on channel 1 only broadcasts in a 1-km radius, another user 2 km away can use channel 1 without interfering with the first user. Reduction in power also means the battery in your cell phone lasts much longer.
This is why Sprint installs so many transmitters.
For the Mars link, NASA uses a dedicated dish antenna 34 m in diameter, and a high-powered transmitter. It also supports communications with just one spacecraft at a time, so there's no need to share the radio link.
answered 15 hours ago
HobbesHobbes
91.3k2256409
answered 15 hours ago
HobbesHobbes
91.3k2256409
answered 15 hours ago
HobbesHobbes
91.3k2256409
answered 15 hours ago
HobbesHobbes
91.3k2256409
91.3k2256409
2
$begingroup$
+15G (specified in the question) also uses MIMO and Beamforming
$endgroup$
– uhoh
13 hours ago
add a comment |
2
$begingroup$
+15G (specified in the question) also uses MIMO and Beamforming
$endgroup$
– uhoh
13 hours ago
2
2
$begingroup$
+1 5G (specified in the question) also uses MIMO and Beamforming$endgroup$
– uhoh
13 hours ago
$begingroup$
+1 5G (specified in the question) also uses MIMO and Beamforming$endgroup$
– uhoh
13 hours ago
add a comment |
Jay Doh is a new contributor. Be nice, and check out our Code of Conduct.
Jay Doh is a new contributor. Be nice, and check out our Code of Conduct.
Jay Doh is a new contributor. Be nice, and check out our Code of Conduct.
Jay Doh is a new contributor. Be nice, and check out our Code of Conduct.
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Have you compared the transmission bandwidths/speeds and the energy used in both cases?
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– DarkDust
17 hours ago
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You could talk to deep space too if you put a 20 kilowatt battery in your cell phone and sat at the focus of this parabola, and still were willing to put up with text messages at one letter per second ;-) planetary.org/blogs/emily-lakdawalla/2011/3253.html The trick to deep space communication lies in a combination of having a large dish at one or both ends of the connection and using one or both high power and low data rates compared to cell phones.
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– uhoh
16 hours ago
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5G differs from 4G in granularity by beam-forming and directing different signals preferentially to different individual users; the architecture requires a higher density and smaller spacing, with lower power per user. Actually answer to Could “live” video be transmitted from Mars? show that video is possible from Mars with current-level technology, but it's not easy.
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– uhoh
16 hours ago
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Related Can I text on my cell phone from the ISS to Earth?
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– James Jenkins
13 hours ago