ASIAIR WiFi -- a synopsis

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W7AY
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ASIAIR WiFi -- a synopsis

Post by W7AY » Sun Apr 12, 2020 9:34 pm

This is a short summary of data transfer speeds of the ASIAIR or ASIAIR Pro in conjunction with WiFi range extenders.

The first column is the ASIAIR type, the second column is the connection method, the 3rd column is the maximum speed, the 4th colum is speed relative to 2.4 GHz WiFi (N300), and the last column are comments.

The "TP-Link" connection method is with the ASIAIR/ASIAIR-Pro directly connected to a LAN port of a TP-Link WR902-AC operating as a range extender using 5 GHz WiFi to connect to the home network. The WR902AC has a maximum speed on the 5 GHz band of about 430 Mbps. The reason the TP-Link is used as an example is that it can be co-sited with the ASIAIR, and operated without any modification from a 5V supply. The extender-limited speed shown below will vary depend on the actual router/extender that is used.

The "LAN" connection has the ASIAIR Pro connected through Ethernet cable to the home router, or to a node of a home mesh network.

The information below come from manufacturing specs and standards, and the benchmarks of the Raspberry Pi 3+ (ASIAIR) and Raspberry Pi 4 (ASIAIR Pro) that can be found here:

https://www.tomshardware.com/reviews/ra ... ,6193.html

Image

Again, please note that a faster extender (e.g., an AC1750- or AC1900-class extender) will allow faster data rates when used with the ASIAIR Pro. With the original ASIAIR, the speed is already limited by the Raspberry Pi 3 hardware, and not by the TP-Link. You do not therefore need a more expensive range extender than the TP-Link when you use the ASIAIR, but you can get better performance with the ASIAIR Pro when you use a better range extender.

The ultimate limitation is the 16x speed of the LAN port (about 950 Mbps, according to Tom's Hardware) on the ASIAIR Pro. The ASIAIR firmware can further limit the transfer speed. If you have a home mesh network, you can just add a mesh node at the telescope itself if you can power the node (an eero node will work from a USB-C Power Delivery at 9 volts, for example).

Clear skies,
Chen

a.cidadao
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Re: ASIAIR WiFi -- a synopsis

Post by a.cidadao » Mon Apr 13, 2020 8:30 am

Thank you, that is very informative and will certainly help me choose my setup connectivity.

Best wishes

António

astrosatch
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Re: ASIAIR WiFi -- a synopsis

Post by astrosatch » Mon Apr 13, 2020 9:12 am

Thanks Chen for your effort to help us get as much as we can from Asiair. I conected tp-link with cable to asiair pro and now is working like a charm. 🙂
Andrej

W7AY
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Re: ASIAIR WiFi -- a synopsis

Post by W7AY » Mon Apr 13, 2020 5:11 pm

António and Andrej,

You are both very welcome.

Andrej, I have been using the TP-Link travel router with the original ASIAIR for a year now -- initially just as a WiFi-to-WiFi range extender (speed limited in that configuration, but gives better range), and ever since ASIAIR v1.4 beta, I have been using a direct LAN cable between the ASIAIR and the TP-Link.

The TP-Link WR902-AC is a moderately old product. The "AC-750" specification is carefully crafted marketing -- it does not really give you 750 Mbps; it gives 300 Mbps to the 2.4 GHz band, and up to 433 Mbps to the 5GHz band.

António, if you are looking for a faster extender options that can be supplied from batteries, take a look at this D-Link unit:

https://www.instructables.com/id/USB-Ba ... -Extender/

This particular D-Link is apparently easy to be modified from a wall plug power to 5V power. I had looked at modifying a AC-1200 class Netgear, but could not find a way to disassemble it :-) :-). On paper, the D-Link should be fast enough (I think it is an AC-1300 class device) so that the ASIAIR Pro will become the limiting factor.

By the way, the D-Link also uses more power since the higher speed also requires a higher transmit power to achieve the same range,

I might switch from the TP-Link to the D-Link if I buy a full frame DSO camera. For now though, the TP-Link is fully satisfactory with my ASI071 camera.

Clear skies,
Chen

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ASIAIR@ZWO
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Re: ASIAIR WiFi -- a synopsis

Post by ASIAIR@ZWO » Thu Apr 16, 2020 6:41 am

W7AY wrote:
Mon Apr 13, 2020 5:11 pm
António and Andrej,

You are both very welcome.

Andrej, I have been using the TP-Link travel router with the original ASIAIR for a year now -- initially just as a WiFi-to-WiFi range extender (speed limited in that configuration, but gives better range), and ever since ASIAIR v1.4 beta, I have been using a direct LAN cable between the ASIAIR and the TP-Link.

The TP-Link WR902-AC is a moderately old product. The "AC-750" specification is carefully crafted marketing -- it does not really give you 750 Mbps; it gives 300 Mbps to the 2.4 GHz band, and up to 433 Mbps to the 5GHz band.

António, if you are looking for a faster extender options that can be supplied from batteries, take a look at this D-Link unit:

https://www.instructables.com/id/USB-Ba ... -Extender/

This particular D-Link is apparently easy to be modified from a wall plug power to 5V power. I had looked at modifying a AC-1200 class Netgear, but could not find a way to disassemble it :-) :-). On paper, the D-Link should be fast enough (I think it is an AC-1300 class device) so that the ASIAIR Pro will become the limiting factor.

By the way, the D-Link also uses more power since the higher speed also requires a higher transmit power to achieve the same range,

I might switch from the TP-Link to the D-Link if I buy a full frame DSO camera. For now though, the TP-Link is fully satisfactory with my ASI071 camera.

Clear skies,
Chen
Hey Chen, how about the test distance of the above results? On my test, the ASIAIR the extender would be better in 10m range and the ASIAIR PRO is 5m, how about yours?
ZWO | ASIAIR Support
Location:lon=120.6 lat=31.3
Suzhou China

W7AY
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Re: ASIAIR WiFi -- a synopsis

Post by W7AY » Thu Apr 16, 2020 11:17 am

Hi Ji xian sheng,

When I checked the radiation patterns, I had measured from a distance of 8 meters (and through one wood wall), which I mentioned in the earlier posting (search for "8 meters" and you should find it :-):

viewtopic.php?f=33&t=10846

You can see from that posting that the orientation of ASIAIR relative to the WiFi router is the most important aspect -- for certain orientations of the ASIAIR, the signal can drop by more than 18 dB.

When it is positioned optimally, the WiFi coverage of the ASIAIR (non-pro) is very similar to the coverage of the TP-Link extender. However, if you mount the ASIAIR on top of an OTA whose orientation (relative to the router) changes during the night, the performance can become very poor compared to a fix mounted TP-Link.

For directions where the ASIAIR (or ASIAIR pro) shows an 18 dB deficit, a fixed mounted TP-Link can improve the distance by a factor of eight. A corollary is that if have WiFi coverage at 16 meters when using a TP-Link, the coverage of the ASIAIR without the extender is reduced to 2 meters or less for some directions.

From what I measured, the ASIAIR pro has a deficit of 18 dB or worse in almost every direction.

Best regards,
Chen

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Re: ASIAIR WiFi -- a synopsis

Post by ASIAIR@ZWO » Wed Apr 22, 2020 8:39 am

W7AY wrote:
Thu Apr 16, 2020 11:17 am
Hi Ji xian sheng,

When I checked the radiation patterns, I had measured from a distance of 8 meters (and through one wood wall), which I mentioned in the earlier posting (search for "8 meters" and you should find it :-):

viewtopic.php?f=33&t=10846

You can see from that posting that the orientation of ASIAIR relative to the WiFi router is the most important aspect -- for certain orientations of the ASIAIR, the signal can drop by more than 18 dB.

When it is positioned optimally, the WiFi coverage of the ASIAIR (non-pro) is very similar to the coverage of the TP-Link extender. However, if you mount the ASIAIR on top of an OTA whose orientation (relative to the router) changes during the night, the performance can become very poor compared to a fix mounted TP-Link.

For directions where the ASIAIR (or ASIAIR pro) shows an 18 dB deficit, a fixed mounted TP-Link can improve the distance by a factor of eight. A corollary is that if have WiFi coverage at 16 meters when using a TP-Link, the coverage of the ASIAIR without the extender is reduced to 2 meters or less for some directions.

From what I measured, the ASIAIR pro has a deficit of 18 dB or worse in almost every direction.

Best regards,
Chen
Thank you Chen, so I got it now, the orientation of ASIAIR (non Pro) is the key point, but for PRO, yes, in every direction, we are working on a solution.
ZWO | ASIAIR Support
Location:lon=120.6 lat=31.3
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W7AY
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Re: ASIAIR WiFi -- a synopsis

Post by W7AY » Wed Apr 22, 2020 8:22 pm

Hi Ji xian sheng,

>> we are working on a solution.

Splendid!

Please consider making it work (and tested) on at least the 5.2 GHz band. 5.8 GHz compatibility is even better for congested WiFi neighborhoods.

The reason is that many routers (the eero is one of them) uses the same SSID for the 2.4 GHz and 5 GHz bands.

If you only support the 2.4 GHz band, at least allow a connection to be made to the MAC address of the router (some WiFi extenders allow this type of connection), instead of connecting to the SSID of the router, since routers have different MAC address for each band.

A 600 Mbps or higher speed on the 5 GHz band would be very useful to support full frame cameras.

I use a LAN connector to go between the ASIAIR and a TP-LInk WR902AC, and I configure the travel router as a 5 GHz band extender. This configuration is very solid (the TP-Link has no problem connecting with the home network on 5 GHz), and I have not had any trouble connecting to my home mesh network (eero) each time I power on the ASIAIR and TP-Link.

By the way, has ZWO considered making a replacement top cover for the ASIAIR Pro that is made from non-metal-impregnated plastic? I am actually surprised that that no one has 3D printed a replacement cover yet. I don't have a 3D printer, or I would have tried it already :-).

Best regards,
Chen

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