Daisy chaining unmanned probes/relays for CommNet

[ryan123]

What are the rules around daisy chaining unmanned probes in Commnet for both science and control?

This is my experience:

I'm decided to setup a ring of simple unmanned relays in a solar orbit identical to Kerbin's. So for example for 3 relays, you'd see in Kerbin orbit: relay, relay, Kerbin, relay (forming a perfect square).

So I went ahead by building a standard probe around the Probodobodyne OKTO, HG-5 High Gain Antenna and RA-2 Relay Antenna. I added batteries and solar panels and off I went launching several of them into Kerbol orbit.

The two first probes were easy enough. They are both roughly 8Gm away from KSP and made direct CommNet connection with KSP. I hit a roadblock however at the 3rd probe, which was around 16Gm from KSP but 8Gm from the probe 1. Probe 1 has the HG antenna deployed, the batteries were charged yet refused to relay to KSP. Instead I'm stuck with probe 3 with direction connection to KSP with 1% strength!

The table at http://wiki.kerbalspaceprogram.com/wiki/CommNet only gives distances for direct connections so I'm in the dark. What rule have I neglected?

 

Thanks!

EDIT:  I'm in science mode and KSP is full lvl 3. Range for the relay is 22Gm to ksp.

Edited January 14, 2017 by ryan123

[Spricigo]

Range=sqrt(antenna strength  1 * antenna strength 2). 

Your satellite has antenna strength 2G (HG-5 makes negligible difference). 

[ryan123]

Pretty sure that's only if KSP is lvl 1. I'm level 3.

[Spricigo]

 

38 minutes ago, ryan123 said:

Pretty sure that's only if KSP is lvl 1. I'm level 3.

This is only relevant for direct contact with KSP.   A single RA-2 16Gm away  will connect with ~25% signal strength, but it don't connect with a identical satellite 8Gm away.  And looks like that is what is happening In your case. 

[bewing]

The specific case that Spricigo means is that if you calculate the range for a 2Gm antenna connecting to another 2Gm antenna, then the range is sqrt (2Gm * 2Gm) = 2Gm.  So you are out of range.

 

[ryan123]

Okay, thanks, the issue is clear now. Back to the drawing board...

[FullMetalMachinist]

13 hours ago, ryan123 said:

So I went ahead by building a standard probe around the Probodobodyne OKTO, HG-5 High Gain Antenna and RA-2 Relay Antenna. I added batteries and solar panels and off I went launching several of them into Kerbol orbit.

Just FYI, you don't need the HG-5 direct antenna. The relay antenna will take care of both talking to Kerbin and to other ships. 

[Argamis]

On 1/14/2017 at 7:15 PM, FullMetalMachinist said:

Just FYI, you don't need the HG-5 direct antenna. The relay antenna will take care of both talking to Kerbin and to other ships. 

Having both a "relay" antenna PLUS a "direct" antenna on the same ship has a combined benefit on signal strength transmission if the science transmitted comes from the satelite itself [but unless it was generated with its own instruments; then this requires a physical "docking" or "manual" (EVA kerbal) conection for storing the data inside the satelite].

There is also a +40% "extra magical bonus" science [as long as the "experiment" can not be sent at 100% of its value [like crew reports]; if it bounces on at least another relay antenna (not in the same ship were the data starts its transmission); this bonus gets diminished if the signal strenght [using only the relays antennas on both ships for the calculations] is not 100% through the whole chain back to Kerbin.

-> This is based on real life "radio experiments" that uses the same protocol for encriptation and error correction to study the space transversed by the radio signals and its carrier beam (since the "real" original information is later reconstructed perfectly, it is posible to use the "errors" themselves as if they were "shadows" caused by the interplanetary medium over the "light" of the transmission).

Edited May 6, 2017 by Argamis

[Spricigo]

4 hours ago, Argamis said:

Having both a "relay" antenna PLUS a "direct" antenna... 

... the signal strenght [using only the relays antennas on both ships for the calculations] is not 100% through the whole chain back to Kerbin.

Both the HG-5 and the RA-15 are relay antennas. And given the fact the HG-5 is much weaker its effect on signal strength is negligible. 

Also, the direct antennas will not affect the power of the relay but will contribute to the strength of a transmission originated from the craft in question. 

Interesting to notice that the relay bonus make advisable to use distinct designs for relays (high antenna power)  and probes l(antenna power in accordance with distance from relay).