Outernet cubesat news


#1

I found and read now this news, about the possible cubesat using for outernet file distributions, in the near future.
http://blog.outernet.is/outernet-is-heading-to-space/


https://www.gov.uk/government/news/cubesats-to-provide-telecomms-through-international-partnership

I dindot find too much technical details in this texts, maybe the core concept is to “boradcast” prepared and on-board saved outernet-contents from cubesat, flying on Low Earth Orbit. I have some paractice to follow such cubesats in radio amateur practices, it seems

  • it accessible in every orbits more or less for some minutes some times in a day
  • it need to calculate the availability on every places, want to receive something
  • it need signiphicant antenna system with tracker machanics, and control, based on the predicted orbits.

Another aspect of such cubesats, the possible upload/control feature.
If somebody on a site has the sophisticated receiver station, with some additional transmitter they will able to upload commands, maybe some user requests, urls, wich can sarve, upload on another ground station site, and will available on the next orbits.
It would be good to discuss about this possibilities.
tjanos


#2

Today,s text at spacedaily:

Clyde Space wins Outernet contract
http://www.spacedaily.com/reports/Clyde_Space_wins_Outernet_contract_999.html
"Clyde Space has signed a 1 million pound deal to build three CubeSats for American global broadcast company Outernet Inc in an international partnership deal funded by the UK Space Agency."

How we will receive the contents:
“The project will see Clyde Space pushing the CubeSat capability to offer a near continuous broadcast of data which will be received on hand-held devices such as tablets and smartphones.”


#3

This is fantastic news that The UK Government will provide 3 Clyde Space Cube Sats.

It changes the whole dynamics of the data feed to a lower orbit and possibly lower cost model.

Well done guys.

Seasalt.


#4

I heard about this looking into some stuff on the ITU, I’m thrilled to see this and yes it should no doubt lower the cost for the vast majority of the system.


#5

Actually, small size and cost of the individual satellite does not immediately lead to a lower system cost. Since we are running a communications mission, the driver of our requirements is power. With deployable panels, a 1U cubesat may be able to achieve 8W of orbit average power. If we put all of that energy into a narrowband, then we have a decent link. But if we want to push more content and data, then we’ll need more bandwidth, which requires a whole lot more power–which means a much larger satellite (20kg vs 1kg).


#6

These cubesats may be able to do provide two way half-duplex communications with the addition of APRS on 145.825.
The thought behind this is APRS messages could be sent on the 2m ham band to these cubesats which could then relay that message to the thousands of ground stations already setup around the world.

This would allow users to request information via APRS radio instead of SMS, in addition this would extend the capability of APRS world wide. If an amateur radio operator wants to send an APRS message via satellite they must use the ISS or PacSat which have passes about 8-15 minutes long. With APRS onboard these cubesats APRS messages could be sent anywhere in the world from nearly anywhere in the world.

Thereby increasing the capability of outernet and at the same time making a valuable communications medium redily available world wide. So even in the event of a wide-scale power outage anyone with a battery powered radio setup could still communicate.

I should also mention APRS would allow users to chat, request data, access email and many other services.


#7

The concept you proposed makes perfect sense. And this may be a possibility. However, there are some operational details to work through, such as interference between too many APRS uplinks on the ground. We’ll have more information on the satellite design in the coming months, which we will be more than happy to share. You can learn more about the radio here:

CMC Cubesat VUTRX CS-VUTRX-01
http://www.clyde-space.com/cubesat_shop/communication_systems/170_cmc-cubesat-vutrx

CMC - VUTRX Factsheet
http://www.clyde-space.com/documents/2776


#8

Thanks for the info. I took a quick look and I do see AX25/1200baud support which is fantastic.


#9

APRS sounds really interesting and I have started researching how I could use satellite APRS on my sailing boat when I go on trips.

I would appreciate any advice as to what design of antenna do I need?

George


#10

Hi Seasalt,
it seems, it is the time to talk a little about the possible receive of the outernet cubesats.
From the Clyde-Space brossure, linked by Syed, it is clear, there will be 2 type of trasmit, one for telemetry, on 144 MHz in aprs. The aprs frequency in Europe, and some other country is 144.800 MHz, in US it is a little different. And it will be broadcast the outernet contents on, somewhere 440 MHz GMSK modulation.
It means you (and we) will need two type of antenna try to receive the signals.
Practically, for the best result, need a high sensitive directional antenna-group, with rotating equipments, and control to track the satellites. This setup is impossible on a sail-boat.
My personal comment:
One years ago, we had a cubesat, Masat-1, it carried transmitter on board, transmit on 435 MHz the telemetry in 1200 bps (not in aprs) and image data on 9600 GMSK. We had a dedicated receiver dongle for it:
https://sites.google.com/site/masatusbrx/
and a decoder program in java, running on the users PC.
Majority of the radio amateurs use they controlled antennas to receive. But I made some experiments with a very simple setup, used a 430 MHz collinear antenna to receive the telemetry. It has some success, mostly the orbits in night-time was able to recive, and the orbits, around 30-70 degree elevations.
There are in commercially available such collinear antenna in the 2 bands, 144 and 440 MHz, I think it can hope will be usefull for simple test setup.
Maybe usefull receive on a boat too.
t.janos


#11

Thank you for the first rate reply.
I am not on the boat all the time so maybe I could set up one of these antennas in the place I rent,

Could you please send a link to these antenna designs etc.

George


#12

I bought the dual-band antenna in a local shop, but it produced by international company.
http://www.dnd.hu/index.php?page=talloz&action=index&kat=230_Diamond_tobbsavos_antennak_Diamond_tobbsavos_bazis_antennak&lang=en


#13

i want to hear and know more about sending data up to a satellite on a standard antenna and also what are the options for more adventurous antenna designs.

I think I might start building a simple antenna and trying to possibly use my rtl sdr et400 ubs dongle that I currently use to decode the aircraft positions etc as a cheap receiver. Are their any sdr programs

I think the Lantern with its 10mb a day would be a very exciting purchase to add.

Could any one please jump in with their ideas and plans.

George


#14

George,
The commercially available, relative simple antenna design I used only to receive telemetry from our cubesat, Masat-1 without any tracking system, and with “modest” success.
But send command to such a small satellite is another story. On this web page you can see the webcam pictures of our new antenna system, prepared for the controll of our new small pocketcube, Smog-1:
http://gnd.bme.hu/kamerak.php


t.janos


#15

tjanos:

I don’t want to hijack this thread, but I spent many years in the design, deployment and testing of ground based satellite carrier monitoring. Basically, we would sample all of the RF channels coming from a fixed orbit satellite, compare power and frequency of the signal against the list of signals we expect, and alarm when someone is transmitting too high, or if a critical signal disappears.

Send me a private message if you would like to talk more.

Cheers,
Brian McIntosh


#16

I suppose you know this proyect https://satnogs.org/


#17

Just had a quick peek - this looks very cool. I may need to set one up!


#18

http://www.uhf-satcom.com/lband/

Could / would the above antenna work on a boat at sea with either a Outernet lighthouse getting high speed data (1 GB a day) or connected to a Outernet Lantern getting the 10MB a day satellite data feed.

It looks very easy to build and may work the RTL SDR Dongle I have.

The antenna on the new Outernet Lantern device looks very small and we have been discussing whether it will only function in a stationary position or whether it could be on the roof of a vehicle and still get 10 MB of Data per day from space.

George


#19

New Lantern is still a stationary device. I’m curious if you actually got L-band reception using RTL SDR, though. How did that go, or are you just planning to do it?


#20

Thanks for the reply Branko I am more just thinking out loud about ideas. I do not want to be the first person to go through the hassle of experimenting on what satellite equipment does work, and what doesn’t work on a tilting sailing boat under way.

But I will be very excited to play with a Lantern and experiment. If it only works in calm situations at anchor that would be fine as well, especially in terms of a $165 device.

I would also like to put a simple antenna up that would allow me to send small APRS data packets etc. up to amateur satellite repeaters as a very basic form of up-link email and possibly have people reply to me using the Outernet $3 per month “twitter” messaging service. Which I imagine is sent almost immediately as priority packets over the Lantern and Lighthouse feed. This would give me a kind of internet chat to the outside world that would be kind of connected to the internet in a kind of real time, depending on how many free to-use satellites go up in the future. ( My feeling is that lots of Cube sats are going to go up.)

Out of interest could you please post the Outernet down-link frequencies or range of frequencies that you expect to use for the Lantern 10 MB per day service.

For the Cubesats what frequencies / Bands do you intend to broadcast on?

What kind of Payload options is Outernet taking on the Cubesats. How much power is available to your payload transmitters.

Are you going to allow APRS repeater function on the Cubesats?

Will the Lantern allow the connection of non dish type antennas i.e flat phased array antennas etc for mobile operation?

I have only used my rtlsdr usb stick to pick up the aircraft ADS-B signals flying over where I live, using a circular DIY half dipole coaxial antenna which allows me to see planes landing 30 km away.

But I see on the internet there are many RTL SDR using them for UHF satellite reception. My feeling was it might allow me to decode some low 1000 ish L-Band . But I am not in a rush, Until you start the 10mb a day Lantern download I am sort of doing other projects first.

George