FEEDACK PLEASE: Smaller Antenna and No Pointing -- Lower Bitrate

In my opinion no pointing is absolutely great. Reducing the bitrate to 1.2Kbps is roughly half the current bitrate which will provide at least 10Mb per day.
No directivity will make adoption of the Outernet receiver by a lot of people more practical since you wouldnt be required to know where the satelite is at all. Am saying this because there a places where there is no internet at all. Apps like Satelite AR require active GPS+Data to get it to show the location of the satelite at your location. So if you have no data,and don’t have any coordinate at all, and with no sense of direction then it will be nearly impossible to get the Outernet receiver pointed in right direction.
No directionality will make it usable in very remote location with no internet at all which is the basics of why Outernet exists.

L-Band pointing with a moderate gain patch is simple enough that I would rather see the current nitrate maintained.

Are you using the Outernet air gap patch? Or another type of patch?

testing flat anntena set up
IMG1 IMG2

stats flat antenna
IMG3

stats antenna pointing
IMG4

Outernet currently supplies GRIB files for small vessels. They are really helpful for safetyand voyage planning. GPS and omni-directional antennae work fine on thise highly moving platforms, but pointing an atenna at a satellite without expensive stabilisers is difficult (cost, power consumption, reliability, etc.).

Two thumbs up for heading towards omni’s at the expensive of lower bitrate.

My experience with l-band patches is based on BGAN terminals (Class 1-3). Set elevation based on a data table, get azimuth close with a compass. Walk it in slowly while watching a signal strength readout. I’ve worked for many years as a SATCOM engineer (mostly field tactical) so I consider it much simpler and easier than manually pointing 2.4-3.8M Ku dish.

@kalashnikov - not fair, your antenna is pointed if you’re laying it flat and you’re located almost at the equator :slight_smile:

1 Like

I would like to see everybody getting another dB and a half or so more gain.
How about an Outernet Stacked Patch Antenna?

More gain equals more pointing.

Thanks,

pointing is not the problem. Reliable reception and higher bitrate is much more important (e.g. emergency situations)

Probably right. It’s just amazing! SNR of 2 is marginal or worse, no good. SNR of 2.5 you will be OK, but probably loose some packets. SNR of 3, maybe loose a couple of packets. SNR of 3.5, maybe loose a packet, good copy. SNR of 4, solid copy. SNR of 5, like to see all the time. SNR of 6-10, probably a dish guy! I’m really thinking of fades, or propagation loss which can be 2 dB.

If the goal is to provide reliable safety/meteo information for mariners: no pointing is mandatory.

Namely for monohull sailing vessels. At sea a monohull will be unable to keep a steady position (in the range of the 40 degrees (?) pointing sensitivity of the current patch antenna) in all the situations but in a flat sea while reaching.

Of course this is just my informed guess.

Testing in the real sea world would be quite helpful.

@JAS - I tested it in my airplane, the antenna was pretty well pointed and I still didn’t get SNR above 0.5 dB.

Increasing the signal not only lowers the requirement on pointing but makes it possible to use smaller footprint hardware and to pick up signals in unfriendly RF environments.

1 Like

In theory, you could have a 19cm copper wire antenna sitting on an aluminium 2mm sheet which is 60 x 60cm (or a magnetic base on top a car), this would be set horizontal and the wire poking up vertically , should receive the Satellite without pointing. Centre feeds the copper wire and the braid/ground is the ground plane aluminium.

Testers?

In a mobile vehicle better off with an omni directional.

Hi

…or increasing the LNA amplification. Adam 9A4QV did not play with 3 LNAs just for fun, I guess.

But that was not the point of my message anyway.

My point was, and is, that for the most likely early seafarers adopters a “no pointing setup” is mandatory.

In other words, for example, for a monohull sailor, let us say of a SV around 28-50 ft it would only be possible to use the current setup when sailing upwind/reaching in a flat or very calm sea (ie, true wind +/- 40-90 degrees) assuming a skilled helmsman or a good auto-pilot in apparent wind mode. For any other situation (the vast majority for most sailors …) the current setup in unusable. Even if reaching, with a choppy sea or waves of around just 2-3 meters and wind gusts, the pitch and yaw motion of the boat are quite likely above the range of the antenna. For points of sailing aft midship and particularly when running dead with the wind (for example, true wind +/- 140-180 degress) even with a calm sea the roll motion is huge.

Using other types of antennas (Helix …) or motors to keep the patch antenna steady would compromise the smaller footprint and would not be attractive to sailors.

So it seems to me that a “no point solution” is really needed to have a viable setup, as far as sailors are concerned.

2 Likes

I am for “no point solution”.

Quite the contrary - - this is a Business Plan issue.

Outernet needs a smaller no pointing antenna, but the same or a higher bitrate. In the geostationary world, the down side is higher satellite power equating to more cost. But there has got to be bitrate to power curve which translates to a bitrate to cost curve. We need to be just below the cost curve cusp

And let’s not forget the low earth orbiting satellites which should come into play downstream which we will need to be omni directional for. Ken

1 Like

I’d strongly suggest that Outernet not design to a lowest common denominator by lowering symbol rate. That limits the whole user world for the needs of a portion of it. It’s surely a no-brainer to want a no-pointing, adequate antenna in any setup, but limiting throughput for everyone to achieve it is probably the wrong approach. You can’t change physics, but there are still more possibilities in antenna design that probably could meet the needs of mobile users, sailors and the antenna-challenged, and perhaps everyone.

Fractal antenna technology allows size reduction, and to a certain degree the ability to warp the physical needs of antenna arrays. Among other approaches, it may be entirely possible to use a fractal array design over a hemisphere shape to garner gain in the critical directions to get good results without ‘aiming’. The good news is that you’re preceded by years of cell phone and satellite antenna knowledge so you don’t have to totally reinvent the wheel. I suggest more research here and then pursue this and similar avenues before adjusting the whole business plan to lower transfer speeds for everyone.

–Lor W3QA

1 Like

I completely agree.

The Iridium Go admittedly on lower orbit Satellites has a very small antenna.

But it also has a baseball size Helical antenna as a option.

Maybe Outernet could sell a optional no Pointing Helical antenna as a accessory.

Cutting the symbol rate in my opinion is to drastic at this stage.

A second option might be like the new Digital television standard from Japan where they transmit (i think) 6 heavy channels and one light channel in the middle that can be decoded by the antenna in a modern mobile phone .

Outernet could have a heavy channel for the heavy downloading a LITE channel for news etc that people could get on the fly with a small no pointing antenna.