Now-defunct-thread-that-should-not-appear-in-google-search.

[BigD145]

I think 1.2.7 was the last 0.22 stable release. Old mods are rarely forwards compatible and typically only if they have no plugins.

[match]

I thought i used standard algebra to find how they got to 742. Pretty sure 742 is wrong and you could have anything in the range of planet radius to antenna/dish/sphere of influence limit for the orbit of kerbin. If mountains don't block things satellites should gain line of sight at 600.01 km orbits, but they would need near perfect positioning. The higher you go the more positioning wiggle room for a 3 satellite grouping.

To reach 742 i think they did something like this.

Distance to horizon before it is simplified can be described as:

(R+h)^2 = R^2 + d^2

R = radius

d = distance

h = height

We are seeking the height that gives a distance of the radius * 2. So d=2R

(R+h)^2 = R^2 + 2R^2

R + h = square root ( R^2 + (2*R)^2 )

h = square root ( R^2 + (2*R)^2 ) - R

Now take a known radius like kerbin and you get: 741.6408...

Mun 247.2136

Minmus 74.1641

Etc. I don't think that gives horizon to horizon view, or 'half' the planet as someone described earlier. That is the distance from the satellite to the horizon -- if it went straight out it would have view of half the planet, but it travels at an angle, so some distance is used to go out and some is used to down -- reducing the field of view to some area short of the horizon.

Your field of view formula probably describes how much of the actual surface is seen.

The formula you quoted results to a constant ratio. You can simply multiply the radius of the body by 1.236.. and get the desired height. I think using "2r" to establish "d" will give you an easy reference to determine the antennae needed to maintain the link between each sat, but it doesn't necessarily need to be this distance. (2*d would give you the separation between sats.)

Yep, the minimum altitude needed for a three sat setup just has to be greater than the radius of the body being orbited (it all boils down to a^2 + b^2 = c^2). Like you said, the minimum allows no wiggle room and is not practical. Not sure why 742 became their magic number, I prefer 776 km for ease of use.

With the field of view, I was looking to point out that 180 degree and horizon to horizon coverage are not the same (I think there was a previous post that mistakenly attributed this to full hemisphere coverage by a single sat). You always have horizon to horizon coverage... that's only a relative perspective. Just need to ensure your FOV overlaps to the next satellite. You cannot attain 180 degree LOS coverage by a single satellite with today's math. It's not just difficult, it is impossible. Now if we could bounce the signal off the atmosphere, that's a different story...

Perhaps the theoreticians can weigh in on it... maybe something like- as the height approaches infinity, time either accelerates to the point where you achieve 360 degree coverage (yay, single satellite coverage!) or ceases to exist and no coverage is possible (boo, no more RT2... or breathing, or universe )

Cheers!

[manatee321]

I've been playing around with Remote tech 2 for about 2 days, and it hasn't been working well. I do like the parts added though for satellites

The connection between craft seems to be not working as in dishes don't work and carry through no connection to craft at about 100km and they don't have any signal at all when map is put onto dish only mode.

the antenna work fine but it seems the dishes have no effect as they are around kerbin at 2,869km~ up i have a few pics in URL form, i might be missing something, but yeh anyway great looking mod!

http://imgur.com/5KaJXmf

http://imgur.com/hPxpcVz

http://imgur.com/uL88VxE

http://imgur.com/wn2IhSy

Edited January 3, 2014 by manatee321
missed a picture

[gardocki]

Do you have line of site to KSC or a relay network that reaches back to KSC?

In RT2 you have to have a connection to KSC to transmit.

I did have a relay network but I figured out the problem. Apparently even if you have a connection to KSC you have to be within the maximum range of your transmitting antenna to KSC or it won't register.

[match]

I've been playing around with Remote tech 2 for about 2 days, and it hasn't been working well. I do like the parts added though for satellites

The connection between craft seems to be not working as in dishes don't work and carry through no connection to craft at about 100km and they don't have any signal at all when map is put onto dish only mode.

the antenna work fine but it seems the dishes have no effect as they are around kerbin at 2,869km~ up i have a few pics in URL form, i might be missing something, but yeh anyway great looking mod!

http://imgur.com/5KaJXmf

http://imgur.com/hPxpcVz

http://imgur.com/uL88VxE

http://imgur.com/wn2IhSy

While KEO Commsat V2 (alt 107 km) has an antenna with range to connect to the sat in the mid orbit, it does not have an antenna with enough range to communicate with the sats in high orbit. Both need to be within range of each other. Once it passes out of visual line of sight with KSC and the sat in the mid orbit, it will become uncontrollable. (Just a guess: Communitron 16 on the sat @ 107 km and DTMS dish on the geosynchronous altitude sats. Comm 16 doesn't have the range to link to the high birds.)

Your spacing of satellites and antenna selection lends itself to this situation. You can put up another mid orbit satellite with a similar orbit on the opposite side , but there are still fairly wide gaps in the network.

Edit: Actually that low bird does have a DTMS dish on it... try targeting the ones in the high orbit, they appear to be targeting Kerbin... the low satellite should be within the cone of any as long as they have LOS.

Edited January 3, 2014 by match

[Cilph]

Going off the grid starting today. I'm aware there are some issues with the 0.23 version but I start my job next monday and I just have so much stuff and moving to do. So hang in there for a week minimum. Internet should come on at my place in two weeks.

[drtedastro]

Have a good move, if that is ever possible...

See you / hear from you soon....

[kalizec]

Good luck!

[manatee321]

Your spacing of satellites and antenna selection lends itself to this situation. You can put up another mid orbit satellite with a similar orbit on the opposite side , but there are still fairly wide gaps in the network.

Edit: Actually that low bird does have a DTMS dish on it... try targeting the ones in the high orbit, they appear to be targeting Kerbin... the low satellite should be within the cone of any as long as they have LOS.

Yeh, it seems the Antenna don't want to pick up the dish signal at low altitudes. The mid range satellite is an exact copy of the one at 100km.

The network is not done, but i wanted to see if they can at least relay a signal to control low orbiting vessels which it doesn't

What is an LOS? (if its an antenna the 16 one that craft in low orbit has one)

For example, I have seen in Scott Manley's videos that he has a relay with dishes that point at Kerbin. He then launches a unmanned craft with and antenna and is getting a connection around its LKO.

I replicate this and the signal doesn't seem to be relayed at LKO

[kalizec]

What is an LOS?

Line of Sight

I.e. the connection mustn't be obstructed by the horizon.

[sonicsst]

LOS is line of sight. If one satellite cannot 'see' another because it is obstructed by a planet or moon it cannot form a connection.

[AdmiralTigerclaw]

I thought i used standard algebra to find how they got to 742. Pretty sure 742 is wrong and you could have anything in the range of planet radius to antenna/dish/sphere of influence limit for the orbit of kerbin. If mountains don't block things satellites should gain line of sight at 600.01 km orbits, but they would need near perfect positioning. The higher you go the more positioning wiggle room for a 3 satellite grouping.

To reach 742 i think they did something like this.

Distance to horizon before it is simplified can be described as:

(R+h)^2 = R^2 + d^2

R = radius

d = distance

h = height

We are seeking the height that gives a distance of the radius * 2. So d=2R

(R+h)^2 = R^2 + 2R^2

R + h = square root ( R^2 + (2*R)^2 )

h = square root ( R^2 + (2*R)^2 ) - R

Now take a known radius like kerbin and you get: 741.6408...

Mun 247.2136

Minmus 74.1641

Etc. I don't think that gives horizon to horizon view, or 'half' the planet as someone described earlier. That is the distance from the satellite to the horizon -- if it went straight out it would have view of half the planet, but it travels at an angle, so some distance is used to go out and some is used to down -- reducing the field of view to some area short of the horizon.

Your field of view formula probably describes how much of the actual surface is seen.

Close.

Since R-tech's mechanics don't actually simulate radio communications, and simply ask: 'is it in range, and is it blocked?', then all you're really looking for is the geometric LoS. (Not atmospheric effects. No signal strength or inverse square law. No radio wave propagation effects or curvature.)

In this case, the geometric distance to the radio horizon is used as defined in the following:

The radio horizon is the locus of points at which direct rays from an antenna are tangential to the surface of the Earth.

Using that definition, we assume that we're going to be dealing with a 'cone' shape in which the satellite is the point, and the edge of the cone represents the lines that will be tangent to kerbin's surface.

If we assume that Kerbin is a perfect sphere (which was explained, terrain mesh has no effect on the radio horizon, only the Sea Level Sphere of the planet.), then we can use the formula without having to do any serious work.

The formula I used calculated the LoS based off radius of the sphere and the height of the transmitter from a sphere. For surface transmitters, this works quite well and I tested comm trucks in-game to verify the distances were more or less accurate. (They were. Give or take depending on terrain height of the xmitters.)

Thus, I worked the formula backwards, where the height was the unknown, and the assumption was that the radius can't exceed 600 km to simplify the math. (IoW, I ignored curvature distance in favor of simplifcation.)

Thinking about it, I realize I do make a simple error in scale. A comm truck's LoS is subject to very little error. In this case, the base of the triangle depicted for it would be very long, and the height very small. Thus, the hypotenuse would be very close to the base, rendering error inert for the purposes of moving a truck around. For a satellite, with a much more normal proportioned triangle, the height will greatly increase the length of the hypotenuse, which means the distance is exaggerated.

Overall, for all intents and purposes, I found that 742 has worked quite well with my sats. I'll do some research and get a more solid calculation done later.

[Shania_L]

Ok guys, I would just like a bit of confirmation here that I am not about to waste a massive amount of time and effort setting a system up, and find that there is a much simpler way of doing things.

I am flying using career mode so my parts choices are limited to the 2.5Mm, 500km Omni and the 50+90Mm Dishes. I am also using FAR, Deadly Re-Entry and ECLSS life support, just to make sure its not too easy

I am still looking to create my comn net around Kerbin itself. My plan is to have a ring of low equatorial orbit satelites at 300km seperated by approximatly 2Mm so they can communicate with eachother. The low altitude is so that I can land ground stations using the 500km antenna which doesn't break on re-entry. I will then setup a seperate polar ring at 1Mm altitude, these higher altitude relays will have 50Mm (the folding ones) dishes for connections to the Mun and Minmus. Ideally I would then like to land a ground station on the north and south poles to provided fixed transmission points to other planets, but that is for when I have some beefier parts to play with.

I am building a lot of redundancy into this system because I am having to launch the satelites individually and I cannot match orbits exactly leaving me with a lot of drift to deal with.

This is what I have so far,

2 equatorial "Achillies" relays as fortune would have it they ended up almost exactly opposite each other, and a single "HARP" polar relay. I can forsee trouble occouring as I cannot get my polar launches to have the same plane, and will end up with my HARP probes orbiting in all sorts of different inclinations.

Also, I note that RT2 has some form of computer packaged with it, I have no idea what this can do or how to use it, so I have left it minimised.

[Umlüx]

i need some help too.. i just got started with RemoteTech and am trying to build up a satellite network.

i have 3 Sats in GKO (KerbNet1-3) and one (KerbNet4) in a very high orbit past minmus.

all are connected.

KerbNet4 should relay all Interplanetary Traffic through the GKO Sats to KSC. therefore it has a KR-7 dish pointed to kerbin and a 88-88 pointed to the active vessel.

now i have launched a little spaceprobe with an 88-88 and targeted it to KerbNet4.. and got no connection.. why?

can't KerbSat4 relay the commands with one dish simply pointed to kerbin?

(please ignore the big orange line, i am on an escape trajectory)

[dlrk]

Can KOS scripts be run from RemoteTech, so as to program, for example, a duna entry, to deal with the delay.

[AdmiralTigerclaw]

Umlux::

Judging from the setup, you have no active link between KerbNet4 and KerbNet3.

Check your sats. Are they all programmed to link to active? If so, that would work fine while KerbNet4 is the active, but the moment you fly your probe, they all retargeted it. Since it's pointing at Kerbnet4, it doesn't notice the other three trying to talk to it.

This is why I really want an auto-receiver.

====

Anyway, I'm doing some Plug-N-chug over here. I've determined with kerbin that the maximum surface distance to the horizon for any given sat is 942 km with lots of decimal values falling in behind it as you stack zeroes behind the altitude value. So no matter how insanely high you push your sats, the maximum surface area coverage is reached when you get up into the 900s range. The 900 km crossover point occurs at an altitude of 7883 km.

At my old selected altitude of 742 km, the coverage radius is out to 664 km, or a little over 2/3 of the hemisphere.

Plugging around, I discovered that as far as the distance curve goes, the gain for surface area falls off steeply after about 1000 km altitude.

All things considered, since perfect hemispherical coverage is a mathematical impossibility, I want to know what you guys think is a 'threshold' percentage of coverage to use as the standard when furthering calculations. 2/3? 3/4? 5/8?

I'll see if I can find an official 'standard' myself.

Edited January 3, 2014 by AdmiralTigerclaw

[manatee321]

Well after some testing, I figured out my problem with the dish system was that the Antenna the 2.5Mm could not reach the dish out 2870Km

I though that if a dish would be able to communicate to an omnidirection antenna as long as it is in the dish range if the antenna could get into comms range angle

Then I figured out dishes can only directly communicate to other dishes at long range, well at least it was a learning process.

But still I'm confused on how other players could have an antenna(2.5Mm) in LKO, still be connected to their relay at 2868Km?

[AdmiralTigerclaw]

But still I'm confused on how other players could have an antenna(2.5Mm) in LKO, still be connected to their relay at 2868Km?

Probably by either:

1: Using an orbit altitude of something like 300 to 500 km

2: Using the 5 Mm omnidirectional antennae.

Or 3: BOTH.

[FITorion]

Probably by either:

1: Using an orbit altitude of something like 300 to 500 km

2: Using the 5 Mm omnidirectional antennae.

Or 3: BOTH.

I do my Omni com sat array using the 5 Mm omni at 400Km... so yeah...

[Peppe]

Well after some testing, I figured out my problem with the dish system was that the Antenna the 2.5Mm could not reach the dish out 2870Km

I though that if a dish would be able to communicate to an omnidirection antenna as long as it is in the dish range if the antenna could get into comms range angle

Then I figured out dishes can only directly communicate to other dishes at long range, well at least it was a learning process.

But still I'm confused on how other players could have an antenna(2.5Mm) in LKO, still be connected to their relay at 2868Km?

What players have that setup? Maybe they are not using the current version or it is a video/screenshot from an old version?

I think remotetech 1 allowed 2 way communication based on the average or longest range of the two antennas/dishes.

Remotetech 2 the comm range is the range of the shortest device.

Not sure how your relay showed connected when it was active. Do your lower KEO satellites have dishes pointing to active ship? If so you can lock them onto your deep space relay.

At your distances you want a dish in LKO to talk to your relay out past the moons. The relay to to have 2 dishes one to point back to kerbin and one to point at the active ship.

So the signal path would be KSC -> Antenna on KEO sat -> KEO Dish -> Deep space Dish 1 -> Deep space Dish 2 -> active craft dish 1

If your KEO comm relay is just antenna's you could launch two dish satellites in polar orbits. They should have antennas to communicate with your local comm relay to KSC. Align them perpendicular and one should always have line of site in kerbin SOI.

[Peppe]

Well after some testing, I figured out my problem with the dish system was that the Antenna the 2.5Mm could not reach the dish out 2870Km

I though that if a dish would be able to communicate to an omnidirection antenna as long as it is in the dish range if the antenna could get into comms range angle

Then I figured out dishes can only directly communicate to other dishes at long range, well at least it was a learning process.

But still I'm confused on how other players could have an antenna(2.5Mm) in LKO, still be connected to their relay at 2868Km?

You might check your units. Your relay is past Minmus ~48mm. Best omni antenna is 5mm. So you are well into to dish to dish only communication range.

[manatee321]

Remotetech 2 the comm range is the range of the shortest device.

Thanks that helped with my confusion greatly, and I was watching Scott Manley. I realized later that he was using the 5Mm, I was mistaken due to their similar appearances........ ;p

[Peppe]

Ok guys, I would just like a bit of confirmation here that I am not about to waste a massive amount of time and effort setting a system up, and find that there is a much simpler way of doing things.

I am flying using career mode so my parts choices are limited to the 2.5Mm, 500km Omni and the 50+90Mm Dishes. I am also using FAR, Deadly Re-Entry and ECLSS life support, just to make sure its not too easy

I am still looking to create my comn net around Kerbin itself. My plan is to have a ring of low equatorial orbit satelites at 300km seperated by approximatly 2Mm so they can communicate with eachother. The low altitude is so that I can land ground stations using the 500km antenna which doesn't break on re-entry. I will then setup a seperate polar ring at 1Mm altitude, these higher altitude relays will have 50Mm (the folding ones) dishes for connections to the Mun and Minmus. Ideally I would then like to land a ground station on the north and south poles to provided fixed transmission points to other planets, but that is for when I have some beefier parts to play with.

I am building a lot of redundancy into this system because I am having to launch the satelites individually and I cannot match orbits exactly leaving me with a lot of drift to deal with.

This is what I have so far,

http://i.imgur.com/BJKbnX7.png

2 equatorial "Achillies" relays as fortune would have it they ended up almost exactly opposite each other, and a single "HARP" polar relay. I can forsee trouble occouring as I cannot get my polar launches to have the same plane, and will end up with my HARP probes orbiting in all sorts of different inclinations.

Also, I note that RT2 has some form of computer packaged with it, I have no idea what this can do or how to use it, so I have left it minimised.

Only issue would be where you want those ground stations. If all they have is the 500km antenna can probably only go 40-45 degrees above the equator before they are out of range. The further up north/south you go the less time they will be in range as the field of view is a bunch of circles moving across the equator -- at the top of the circles covered will go in and out as the satellites move. The satellites at 300k cannot see much further than the 45-50 degree north/south.

What information mod are you using for orbits? With low orbits you run into an accuracy issue. I use VOID to see accuracy of the orbit semi-major access down to the meter, but the game bounces that last meter around whenever it is in physics range, so when synced up my sats I do it down to that last meter.

At 300km your orbits are under an hour, so if you warped say 100,000x to line up a shot to Jool your orbits could move even in an ideal case 5-6 meters a day and pretty quickly they won't be a reliable relay.

Given our accuracy is ~1 meter per orbit, the higher you can take the orbit the longer their relative distance to each-other will hold and the longer your relay will operate without adjustments. If you have a healthy overlap in coverage say you are at 600km with 4 satellites, start them in a box shop and they won't fail until the sides collapse down to a triangle shape.

If you don't use void and instead use kerbal engineer or mechjeb that don't show semi-major axis or go on just orbital period down to the second/tenth of second your orbits relative to each-other could be much more than a meter off.

Land based polar dishes for deep space is an interesting plan and think that part is solid. I don't think there would be a blind spot. The sun may still get in your way.

Edited January 3, 2014 by Peppe

[Peppe]

Umlux::

Judging from the setup, you have no active link between KerbNet4 and KerbNet3.

Check your sats. Are they all programmed to link to active? If so, that would work fine while KerbNet4 is the active, but the moment you fly your probe, they all retargeted it. Since it's pointing at Kerbnet4, it doesn't notice the other three trying to talk to it.

This is why I really want an auto-receiver.

====

Anyway, I'm doing some Plug-N-chug over here. I've determined with kerbin that the maximum surface distance to the horizon for any given sat is 942 km with lots of decimal values falling in behind it as you stack zeroes behind the altitude value. So no matter how insanely high you push your sats, the maximum surface area coverage is reached when you get up into the 900s range. The 900 km crossover point occurs at an altitude of 7883 km.

At my old selected altitude of 742 km, the coverage radius is out to 664 km, or a little over 2/3 of the hemisphere.

Plugging around, I discovered that as far as the distance curve goes, the gain for surface area falls off steeply after about 1000 km altitude.

All things considered, since perfect hemispherical coverage is a mathematical impossibility, I want to know what you guys think is a 'threshold' percentage of coverage to use as the standard when furthering calculations. 2/3? 3/4? 5/8?

I'll see if I can find an official 'standard' myself.

~942 makes sense since that is the circumference of kerbin / 4.

Thresholds that would matter are things you could cover/reach at those places.

For KSC coverage -- sits on the equator it is simple. I have 3 satellites I need 33% coverage. 4 satellites = 25% coverage and on down.

What other points are interesting? Maybe some continent you could cover? Maybe how far to reach the polar region?

Simplest comm relay to deploy that gives 100% coverage of the globe?

[AdmiralTigerclaw]

~942 makes sense since that is the circumference of kerbin / 4.

Thresholds that would matter are things you could cover/reach at those places.

For KSC coverage -- sits on the equator it is simple. I have 3 satellites I need 33% coverage. 4 satellites = 25% coverage and on down.

What other points are interesting? Maybe some continent you could cover? Maybe how far to reach the polar region?

Simplest comm relay to deploy that gives 100% coverage of the globe?

My biggest concern is connection reliability and redundancy.

I don't much like working on a long range probe if at the critical time in flight, the connection drops out because there's a hole in the network.

And the biggest cause of holes is the rounding error from things going on the rails. Without time warp, a well placed constellation takes a long time to drift out of phase. Once Time Warp kicks in, the entire thing becomes a mess in the time it takes to send a ship to minmus.

So I try to set up a network that maximizes uptime while mitigating any down time ASAP.

Uptime tends to result from a combination of coverage and link redundancy. The more links I have between sats that have wide coverage area, the better the uptime.

In this case, my primary goal is to keep the primary link to KSC up to about 99.99% (Mathematically, there WILL be a gap at some point in the game, meaning it is impossible to achieve perfect 100%)

In order to ensure I have coverage and connections, I consider that my satellites have a very wide field of view of kerbin, while also being close enough that I can get them to cross-communicate with each other unless they're ocluded by kerbin itself.

This way, even if they bunch-up in their orbits due to time warp, they still have LoS and range to talk to other satellites in the constellation.

Like this group:

I forget what sat set that was, but even though the two up on the top side of the picture are bunched up, it's clear by the cat's cradle of connections that even if they get wonky, down time remains very low.

And in the image, the sats that are in lower standby orbits have higher frequencies, which allows them to swing around and clear gaps in coverage that could pop up due to drift. That's not intentional however, just a side-effect of popping a bunch into LKO first, then seeing how many I need to place.

Going for simplest is a good goal, but in my opinion, it's too easy to 'break'.