Author Topic: OGN-R uplink typical range  (Read 3982 times)

rogerabc

Re: OGN-R uplink typical range
« Reply #30 on: August 25, 2020, 05:50:28 pm »
Thanks Peter, I had not realised that.

However, I monitor audio from PAW and SD and do not want to receive audio warnings about distant traffic.
(PAW audio seems superior to SD traffic related audio.)

Ideally I would like to filter traffic separately from ground stations.
Roll on the new developments.

exfirepro

Re: OGN-R uplink typical range
« Reply #31 on: August 25, 2020, 07:32:40 pm »
Roger,

You shouldn’t get PAW audio warnings for ‘Known Position’ traffic from further out than 10Km and +/- 2000ft and can reduce this to 7, or even 3Km (with comparative relative altitudes) by using ‘Positional Contacts Settings - Select Audio Warning Zones’ in the ‘Positional Contacts Settings’ section on PAW / Configure.

Audio warnings for ‘Bearingless’ traffic are controlled by your chosen setting in ‘Mode C/S Horizontal Sensitivity’. The normally recommended ‘Short’ or ‘Medium Range’ should start to produce Alerts at somewhere between about 3 - 5 miles (approximately - as this depends on lots of variables at each end of the transmit - receive link). The exception is the known anomaly of high power (CAT) transponders, which at up to 500 Watts at the antenna, can trigger audio alerts from significantly further away, - though these normally present a clearly recognisable ‘signature’ as they tend to go straight to ‘Traffic Danger’ without prior warning, or very rapidly through ‘Traffic Notice / Alert / Danger’ - while still outside normal visible range.

Hope this helps

Best Regards

Peter

rogerabc

Re: OGN-R uplink typical range
« Reply #32 on: August 25, 2020, 08:29:35 pm »
Yes, very helpful thanks Peter,

I always found those settings slightly confusing & now I understand them just before the update. ;D

Hope to update & test fly with new antenna tomorrow.


buzz53

Re: OGN-R uplink typical range
« Reply #33 on: August 28, 2020, 01:53:35 pm »
Lee,

Thank you for that detailed reply earlier regarding the filtering out of ground stations in track logs. Unfortunately I can only agree with a little of it. Of course I sympathise with your support loading, and clearly if you can automate some of it that would be a good thing, but by depriving people of an easy way to sort out their own installation I’m not convinced you are making it any easier for yourself.

Clearly I can’t tell from your rather general description what you’re actually proposing to provide from the telemetry you’re gathering. I’m sure it will be very useful for general system performance monitoring and presumably will provide metrics like “78% of users have contact with a groundstation for 82% of the time” or “your installation scores 7 on a scale of 0 to 10” etc.

I really can’t see how this helps individuals, with all the variability of individual installations and performance of local groundstations to know what they are actually getting, and what to do about it, and I wonder how long it will be before this is publically available in an automated form.

I strongly disagree that allowing people to self-analyse is in any way difficult or undesirable. There is no need to wade through large text files as you suggest. James Roses’ fantastic track analysis tool allows you see in the simplest possible way how well an individual installation is performing in terms of range on various bearings etc. etc.  I have suggested to him that it would be even better if the track colour could be changed to indicate where in the flight the uplink was working or not. What could be easier than that? I have made good progress with my own installation, on which I will report in due course, due to this tool.

I really can’t see how some online tool, especially relying on secondary data via the downlink rather the raw data in the track filter, can be any easier or better. People are either interested in knowing how well it works and fixing it, or not.

I cannot see a single good reason why the ground stations should be filtered, and so I do wonder why you are doing it? It doesn’t affect me at the moment as I am using Skydemon audio and set my filters wide, but many people will want to use PAW audio. Why deprive them of the ability to use this facility, for no positive reason?

Please reconsider before your upcomong release! I'm sure it is a trivial mod!

Kind regards,

Alan


buzz53

Re: OGN-R uplink typical range
« Reply #34 on: January 07, 2021, 10:40:04 am »
Lee,

I have been asked about the display and reporting of groundstations being affected by the PAW height and range filters, as we discussed on this thread back in August. Is this still the case with the latest software and new log format? There are three questions really:

Do the filters affect the in-cockpit display of groundstations on PAW itself?
Do they affect the groundstation reporting to e.g. Skydemon?
Do they affect the groundstation display on the Aircrew track replay utility?

Unfortunately I can't really check it out myself at the moment!

TIA
Alan

Admin

Re: OGN-R uplink typical range
« Reply #35 on: January 07, 2021, 01:23:38 pm »
Quote
Do the filters affect the in-cockpit display of groundstations on PAW itself?
Not sure I understand the question ?
Do you mean the web server traffic/radar page ?
The traffic page - no
The radar page - yes

Quote
Do they affect the groundstation reporting to e.g. Skydemon?
yes

Quote
Do they affect the groundstation display on the Aircrew track replay utility?
yes
« Last Edit: January 07, 2021, 01:25:28 pm by Admin »

buzz53

Re: OGN-R uplink typical range
« Reply #36 on: January 07, 2021, 05:52:51 pm »
Thanks Lee, but we may be at cross-purposes as I think you are describing filtering of aircraft? I was asking about groundstations. Back in August, we agreed (I think!) that the range and height filters also affected groundstations, so that if somebody set filters at plausible values of, say 5nm/1000feet, then groundstations outside that range would not be seen at all, not in the PAW radar, nor Skydemon nor the groundstation post-flight analysis. This would lead to very pessimistic and incorrect evaluation of uplink range.

I recently repeated that information to somebody but then realised the PAW software was changed radically in Spetember, so wondered if it is still correct? In particular I was interested in the Aircrew replay, as it seems to use the new $PALOG RF entries which may no longer be range filtered?

Hope that's clearer now.

Alan

Admin

Re: OGN-R uplink typical range
« Reply #37 on: January 07, 2021, 06:25:24 pm »
Hi Alan

Quote
we may be at cross-purposes as I think you are describing filtering of aircraft?
When any object is reported to a navigation device SD etc, it is subject to any filters you apply, so in other words the $PFLAA messages are constrained to within the horizontal & vertical bounds.
There is an additional message for ground stations sent to SD using a bespoke message, this message is also constrained by the same requirements above

Quote
if somebody set filters at plausible values of, say 5nm/1000feet, then groundstations outside that range would not be seen at all, not in the PAW radar, nor Skydemon nor the groundstation post-flight analysis.
That is correct if the filters are set to anything other than the default
This is the purpose of the filters, they were actually intended for systems such as some of the glass cockpit systems, which do not have filters.

Quote
This would lead to very pessimistic and incorrect evaluation of uplink range.
Agreed, if the evaluation (erroneously) does not take the filters into consideration, then the evaluation is incorrect.

Quote
I recently repeated that information to somebody but then realised the PAW software was changed radically in Spetember, so wondered if it is still correct? In particular I was interested in the Aircrew replay, as it seems to use the new $PALOG RF entries which may no longer be range filtered?
I think I now see your confusion, the PALOG entries are for internal debug usage only, are not intended for user consumption, and are liable to frequent changes - and yes they do contain some experimental data to capture more information of the surrounding RF environment.

thx
Lee

« Last Edit: January 07, 2021, 06:28:30 pm by Admin »

buzz53

Re: OGN-R uplink typical range
« Reply #38 on: January 07, 2021, 07:00:09 pm »
Great, thank you. But at the moment then, with the current software version, if using the Aircrew replay tool to view the uplink range (which is really the only way a user can readily do so), will that be affected or not by the filters?
Alan

PaulSS

Re: OGN-R uplink typical range
« Reply #39 on: January 08, 2021, 07:05:14 am »
Quote
if somebody set filters at plausible values of, say 5nm/1000feet, then groundstations outside that range would not be seen at all, not in the PAW radar, nor Skydemon nor the groundstation post-flight analysis.

Quote
That is correct if the filters are set to anything other than the default
This is the purpose of the filters, they were actually intended for systems such as some of the glass cockpit systems, which do not have filters.

Well, every day is a school day. I certainly didn't realise that ATOM stations would be treated the same as aircraft as far as filters were concerned. So, if the filters were set as 5nm/1000' then at 2000' I wouldn't receive an ATOM uplink (including METAR, Flarm etc). This means I might have Flarm traffic within 5nm/1000' of me but I'm not going to see it because the 'aircraft' filters are applied to the ATOM stations. I might be 1nm away from the station but at 2000' and won't see any ATOM data! Is that correct? If so then I think that needs a re-think.
« Last Edit: January 08, 2021, 07:07:53 am by PaulSS »

buzz53

Re: OGN-R uplink typical range
« Reply #40 on: January 08, 2021, 08:37:04 am »
Hi PaulSS, no it's just the display/reporting of the groundstation itself that's filtered, not the aircraft it is uplinking.
Alan

Admin

Re: OGN-R uplink typical range
« Reply #41 on: January 08, 2021, 08:39:48 am »
Hi Paul
To be clear
All the filters control is the display of the position of an object
So if a rebroadcast object (flarm aircraft) is within filter range it is displayed

This is not the same as the ground stations position

Thx
Lee

buzz53

Re: OGN-R uplink typical range
« Reply #42 on: January 08, 2021, 11:28:17 am »
Lee, going back to my last question which you perhaps missed, and avoiding internal techie details if you prefer, I still think it is of interest to any user to know whether, if they replay their flight in the Aircrew tool, they will see the in-range uplinking groundstations regardless of the range filter settings?

Alan

rogerabc

Re: OGN-R uplink typical range
« Reply #43 on: January 08, 2021, 12:19:35 pm »
I am also interested in this question.

Vector seems to measure downlink range but my flarm glider avoidance relies on uplink range.

Is that right?

Roger

PaulSS

Re: OGN-R uplink typical range
« Reply #44 on: January 08, 2021, 04:02:16 pm »
Sorry for the attempted thread derail and I am very pleased I misunderstood the system. Back under my stone I go  ;D