In my experience, rain and fog do attenuate wifi signals quite a lot. Both wifi and microwave ovens use frequencies around 2.4 GHz. Maybe that is the clue? Microwave ovens heat the water in food, so water must absorb radio energy very well at that frequency.
@@SteveWrightNZ If you designed your pathways with good RX\TX and they don't failed in rain, that's not empirical evidence that H20 molecules don't absorb 2.4Ghz RF. Because they do, therefore 2.4Ghz is attenuated, that doesn't mean your link will just drop. RSSI values just become lower.
My experience is that I have been using a flat panel wifi antenna to connect to a free public hotspot in a building some distance from my flat. At the best of times the connection can be a little slow but useable. In rain and fog it does not work at all.
6:40 When considering the Fresnel zone this location is line of sight (light) but still not good for RF communication with trees and power lines inside the Fresnel zone. And the helix antenna is circular polarity and will have significant polarization loss against a vertically polarized antenna.
@@AndreasSpiessYou should be lost at least -3DB for using a circularly polarized antenna with a vertical antenna. I would recommend you to use a parabola antenna to get a higher gain.
@@AndreasSpiess I noticed you running cross-polarized antennas in your LoRaWAN distance tests starting with your gateway having a antenna that was 10° off vertical. This is something to avoid that is emphasized in the ARRL's educational literature as you'll lose 20dB when you use orthogonally polarized antennae. www.mtiwe.com/?CategoryID=353&ArticleID=163
@@AkawichPonIn The circular polarized is actually not a bad choice. Just because it attenuates any linear polarized signals (or noise) by 3dB or more. And most noise, WiFi and Bluetooth is linear polarized. But of course you need the "partner" to be polarized in the same twist. 73 de LA8BKA
Follow my prior comment : Wind usually associate with rain but fog. Antenna set in vibration in windy day, rain or shine, can make matter worse, with unwanted amplitude modulation that convoluting the wanted signal by a vibration magnitude and rate. I agree with other commentator that flat antenna in video has feed port point sideways but downward. Can contribute 3 to 20dB polar mismatch loss to a linear antenna at the far end.
Nicely done! That was a lot of work. Long range mode is a little disappointing, I was hoping for better. Well, these things advance in small steps. Thanks for sharing your results.
Weather is a problem f of water is 2.4 GHz, so trees and rain/for are a big no :) also try pringles and yagi antenna. Back in a days, around 16 years ago we manage to make stabile links with WiFi antenna made with satellite dish and yagi inside dish, we manage to reach 5-6 km in city and more than 30 km outside urban areas with Ateros chips since you can go a little outside regular WiFi freq. :) not so legal but it works :)
I think you can improve the RSSI values if you use the same polarization in both transmitting and receiving antennas. I noticed that the panel antenna on the pole is using vertical polarization in contrary to the panel antenna inside the car which is using horizontal.
yup theres atleast a 3dB loss there ... RX and TX antennas should ideally be identical, both in dimensions and orientation..mixing horizontal with vertical and circular is very bad practice!..(even upto 30dB loss when mixing circular with horizontal or vertical)
@@AndreasSpiess 3dB is the loss from circular to linear. Linear Vertical to horizontal losses are greater. see www.antenna-theory.com/basics/polarization.php
@AndreasSpiess if you have a polarization mismatch of 90 (270) degrees in theory, you will have infinite losses, in practice is between 25dB and 30dB. 3dB losses is if mismatch is 45 (135, 225, 315) degress or if you use combination of linear and circular polarizated antenna.
By the way, may I suggest an alternative to the box? Blue Ikea bags are cheap, robust and lightweight, and once folded takes no space. When I worked as a field technician used it to transport up to 15 Kg. Can be handled using only one hand or carried in the shoulder. And in several occasions used them as a cover under the rain (they are waterproof).
Patch Antennas were not located correctly! This can be seen on video 7:45 and 6:55. The fact is that the patch antennas have a clear vertical or horizontal polarization. The spiral antenna has circular polarization. Therefore, for a spiral antenna, it does not matter what position it is in. For the Antenna patch, it is important that the cable goes down both on the transmitting antenna and on the receiving antenna.
Just because the patch antennas appear to exist in two dimensions, it does not mean that they exhibit only linear polarizations. Patch antennas can be fed in a manner that produces circular polarization. If a single patch is fed from the side it is usually linear. If fed into the patch directly to a point inside the perimeter it can produce circular polarization. Many panel antennas are actually 2-4 patches which may individually be linear polarized but phased to produce circular pol.
Nice Video Andreas, but i think youre missing a major key to antennas...Polarization... youre mixing horizontal with both vertical and circular polarization... there can be upto 30dB loss between horizontal/vertical to circular...and about 3dB loss between horizontal and vertical...you should be using the same antenna (dimensions and polarization) on both the RX and TX sides
You are right. I did not consider polarization. I was not aware of the 30 dB. I was aware of the 3 dB between horizontal and vertical. But with all my tests I was not able to see big differences. If circular is so different I have to look into it. Also which polarization a panel antenna has
I have definitely noticed that the rain will not allow my esp8266 to send out the temperature from my chicken coop which is a good distance form my access point. Great video, as always very interesting!
Bravo! Such a great series of tests that for someone who knows little about radio and antennas but who finds the concept of action at a distance fascinating, were both useful and interesting. I have experimented with a commercial Yaggi antenna to connect the IP camera in the stable where i have my pony with my home wifi over a short distance of about 25 m, but although I had a little success it was not reliable, but I have managed to get a connection via the main cable with suitable devices and have given up on the Yaggi for now. However, I may revisit it as I have cabins at over 100 m that it would be useful to have wifi in. Just have to be motivated when i have time, the former easy, the latter not so. Thanks for sharing!
From an 'easy usage' point of view, it would be nice if they came pre calibrated. But as a viewer, no way am I submitting myself to calibration. I'm also glad they come in different pin configs too. 😁
Z=140xC/Lambda Now, to get a standing wave axial type helical antenna we want C=lambda. Which means were pretty much stuck with a 140ohm antenna. Now i don't how how it will affect beam forming or matching but using three perfect helical antenna with a matched 50ohm cable will give 140/3 roughly 50 ohm to get work done.
Hello! Really like your videos. But you need to do something with the microphone cable, probably change it to shielded, when you watch your video in the headphones in the left channel, you can constantly hear background noise from the computer or something else. Thanks for the videos!
Gruezi. What do you think of the crude methods to add an external antenna to an ESP devboard v1 that only has a PCB antenna? Is there any chance to tinker with it such that we can match the impedance properly?
I use an outdoor square type 2.4 GHz patch antenna for regular wifi to get it from remote router. I am always surprised that it works just as well even if there is torrential heavy rain or snow storm. The thing that has effected the signal the most was a heavy dew on tree leaves when the sun is at a low angle when coming up in the morning. But soon as the sun rises higher the wifi signal would come back okay. There are some hams in town near here using Aredn Mesh firmware in routers that are capable . On the ham bands certain frequencies are in standard wifi ranges so it allows the use of much higher power if someone wants to. I haven't gotten around to trying it out yet.
I can imagine that wet leaves are a reasonable ground quite high in the air. But good to know that fog is no problem. And I also read about these mesh networks, but never tried it myself.
Hi, can i ask one question Herr Spiess? I'm searching for some kind of power on reset device for esp8266, so if my solar weatherstation falls out because the overnight drained battery, when reaches again safe voltages it resets the esp! Thanks
there is a great parametric design of a helicalantenna on thingyverse. using it for 5.8ghz video and outperforms any antennas I have bought that advertise same specs and is even quite rigid (the death of my self build helicals with cardboard was always because i threw them in a backpack and the copper wire deformed. not so with the design from thingyverse)
Question: Does usable range imply both Signal from Site A can be received at Site B AND that it can receive signal from devices at Site B trying to communicate back to Site A? I moved to the beach recently. I’d like to extend WiFi coverage approximately 250 feet to the beach . I do have direct LOS from second story of house to desired area of beach about 250 feet. I’d like 5gig coverage for iPhone and laptops. If a long range Access Point states its service is usable at 300 METERS, 1) that seems more than enough and 2) does that imply that Iphone and Laptop device's WiFi signal can be received by that LR Access Point?
Servus! Du, was ist mit den 2,4 GHz Lora Modulen geworden ? Das wäre ein Interresantes Thema, auch für Datenübertragung möglich ? Schaue immer gerne wieder rein ;)
@@AndreasSpiess Es gäbe auch einen Sateliten (21.07 Launchdate) der 2.4GHz Lora Überträgt. Ich denke aber, das die Übertragung eher schwierig sein kann. Ich finde deine Beiträge immer Ideenreich. DANKE mach weiter so ^^ ich weiss was das für ne hacke ist
Wir haben ja bereits einen Satelliten der auf 2.4 GHz (und 10GHz) arbeitet. Er ist geostationär und heisst QO-100. Du findest Videos wo ich eine Bodenstation gebaut habe...
Hi Andreas thanks for the great video as usual! If I'm not mistaken, you didn't yet investigate further the difference between your homemade antenna and the commercial one? In case I am incorrect, can you please provide the link to this "mystery video"? Thank you! :-)
@@AndreasSpiess Thanks for answering :-) I hope you will eventually find the time and/or interest to revisit this, it's very interesting in my opinion!
Hi Andreas. Did you care about the antenna polarization ? If your antennas are not with the good one there are big losses. As example: using two different linear polarization, there is 20dB of attenuation. As you use circular polarization, and if I remember my radioamateur experience, you must use one right hand and one left hand polarization. In an other way, it is not because an antenna has a good VSWR proove that is a good antenna (see VSWR with a dummy load). Hope this could help. regards F1SLU
You are right. I know about polarization, but never exprienced huge losses or wins on these high frequencies. And very often you cannot match porarization if the devices move (e.g. smartphones). I always thought the loss between horizontal and vertical polarization is 3dB. But I did no research.
Andreas Spiess Theoretically, line of sight reflection free polarization mismatch of perfectly linear polarized antennas can be infinite loss and not 3dB. Practically antenna system imperfection, imperfect linear polarized and stray reflectors may contribute cross polarizations allows an infinite loss to be finite loss. A polarization mismatch link between linear and circular antennas in free space is expected to be -3dB.
I am new to projects like this. I dream about making a portable transmitter/receiver for the common signal types like cellular, GPS, WiFi, bluetooth ANT+ and wonder what it would look like to make the form factor ideal for the antennas and portability. My thought is that it might be a good experiment to consider tethering various devices from such an antenna hub based on the contexts that you would use them instead of trying to continue to pretend that cellphones are good for everything. I could use advice on what direction to head to get the supplies and skills I need. Thank you for your excellent videos.
Very interesting... I look forward to your further investigations. I haven't really played about with antenna construction much since the CB days, which being 27Mhz involved somewhat larger (impractical) engineering! I wouldn't worry about political correctness, it's gone mad. People who just hear words but ignore context are just revealing their own inner issues. Thomas Sanladerer, the 3D printing guy, was stumbling all over this on a video about SPI, and the meaning of the MISO and MOSI acronyms, causing much amusement in the comments.
Is there any chance of producing a comparison of commercially available stub and whip antennas? I remember from earlier videos that some Chinese antennas were tuned to the wrong frequency and one or two were OK on 2.4GHz. I need to mount some ESPs, via uFL to SMA, in metal boxes and I need to find usable antennas for them. Thanks
The dealers on Aliexpress change their suppliers quite often. So it would make no sense. The only thing you can do is measure yourself. Or by from trusted suppliers. Sometimes even two antennas of the same packet are different.
Did you take the beam width of the antennas into account ? I noticed that the antennas are dangling from the mast. If the beam width only is a few degrees it makes a lot of difference.
I guess the beam width is about 30 degrees. Have a look at the radiation pattern polar plot: www.comsol.com/blogs/analyzing-operating-mode-options-for-helical-antennas/
Is not correct, because helix antenna have circular polarization, but patch antenna v-h. That's mean 6 db loss for helix, but thus helix independent for source orientation. Caution, helix create interference for both polarization v and h at the same time.
You are right about the loss between vertical and circular antennas. I do know which polarization my patch antenna has. My POTY 2.4GHz patch antenna, for example, is circularly polarized.
Short question. If I have an esp32 with an MQTT client with LR configured, is there an easy way to get it to an MQTT server in the cloud. The esp32 access point will be configured in LR mode also. So the esp32 LR appears to form an isolated island. It would seem to require a Bluetooth or serial link to another esp32 in normal mode. Is there a better way
I did not look into using a ESP32 as a bridge. If you look at the sketches I used you see that the master first connects to a regular AP. So it should be possible to use this one as a bridge.My topic was more the LR mode.
There was less difference than you think. The transmitters were the same modules. The receiving s ich de was completely the same as I changed the Sketch f oh r the different Tests. The transmitting antennas were different.
Hi Andreas, you have lots of experience with ESP32. My ESP32 disconnects irregularly from wifi within 1-2 days always. Did u encounter this issue? What it could be? Many thanks!
Hi do you know any solution for transmitting and receiving data low power? eg temperatur data sending and receiver both with a couple of aa batteries? nrf24, rfm95..they all need too much energy in rx mode. I'm searching for over an year now..
Really in RX mode and battery powered? As my searching there seems no other solution than a ook receiver. All the chinese stuff, wirelss door bells, thermometers..they all worked with simple ook receivers and many many month with just two mignon cells
I think the effort to reduce the use of the possibly offensive terms "Master" and "Slave" is mostly centered around IS orgs in countries with a fairly recent histories of a race based slave trade... i.e. the United States. I know that my employer has done their best to reduce the use of the terms and, frankly, I don't think any of us really care. It's not that hard to use alternative terms like Server/client or Primary/Secondary, whatever... and if it makes one or two people I work with feel a bit more comfortable, why not? I'm in a mixed race family and don't really care, but maybe it annoys someone else?
Cool. But I just sent a first Hello World message using a NB-IOT network. No need for big antenna's. T-Mobile offers a free sim card to play around with for a year. Maybe you can do a vid about these too.
@@AndreasSpiess Are you suggesting your area isn't covered yet? I expect my nb-iot device to work if I would bring it over there and plug a battery in. A search on google tells me that Swisscom has completed rollout in Switzerland as per June 2019. Not sure if you can get a free sim to play with. www.digitalkeys.io/nb-iot-network documents.swisscom.com/product/filestore/lib/7247d9ff-14e6-408a-9982-c0589b688912/brosch%C3%BCre_connectivity-en.pdf (page 8)
Hii great video. But I have some different issue. I'm getting exemption (9) and board resets. But I don't want it to happen. It's not a big code but I don't want it to restart like that .. I tried adding delay to it but didn't worked.. please help me with this, can't find another person with this kind of depth in esp. Tq in advance..
Hello Everybody! Do you think ESP32 LR or LoRA are good ideas to consider when i'll try to connect my apartament with my basement in multi-occpupied building? I live on 5th floor and basement is on -1. There are many, many layers of reinforced concrete between us :( Any ideass greatly appreciated! Cheers!
@@AndreasSpiess Possible depends on the country? I think some countries may use 3-phase mains? So it may be hard to find a power outlet in the basement on the same phase as the apartment?
i bought a powerline (cheap) speed reduces with length of electrical cable. if u have ups/inverters, they cause additional interference. ofcourse, 3-phase wiring means it may not always be successful. best solution till now is to use cat 5/6 cable from the router and add an accesspoint at each floor (concrete has steel reinforcement which eats all the signals, so they don't travel across the floors). But in the case of cat cables, rats don't like them. so these cables need reinforcement (from rats)
@@dd0356 I have 3 phases in my apartment, although basement may be connected very separate way. It's 7-story building, with 8 apartaments on each floor :( My last chance is GSM as it works well even underground, but it's additional cost every month to pay pre-paid internet on simcard working there. Thank you for your responses. Cheers!
Water abdorbs 2.4GHz www1.lsbu.ac.uk/water/microwave_water.html Airborne droplets will do transmission range no favours at all. 😕 It gets worse with salt spray... Not a problem in Switzerland but worth considering ocean-going or even coastal applications where one might like an RF bridge to a smsll island without Internet.
Great video, however, not really sure what to think of it... longer is better, sometimes thicker is better... political incorrect sketches... Very confusing. One thing I'm sure of... size does matter !
Hi Andreas, I'm Marco from Bavaria. Thank you for your time and great tutorials. I know this video is related to WiFi transmission but since you are a great fan of LoRa, I'd like to ask you a specific antenna question there: To my knowledge, the ISM regulation in Europe is 14dBm (=25mW). I see a lot of dipole LoRa-antennas with a gain of around 2.1dBi. For a specific project, I'd like a gateway to be able to listen with a long-range antenna. There are a couple of YAGI antennas with gains of 11dBi or even 23dBi available and can be sourced from digikey: www.digikey.de/products/de/rf-if-and-rfid/rf-antennas/875?k=yagi&k=&pkeyword=yagi&sv=0&pv1851=291672&pv1851=299188&sf=0&FV=-8%7C875%2C1850%7C417331%2C1850%7C417333&quantity=&ColumnSort=0&page=1&pageSize=25 Do you think it is possible to connect multiple antennas over one HF port on a LoRa gateway (like the ones from Dragino or RAK). I can imagine that the signals of two antennas could interfere on the one hand. On the other hand, if the 2.1dBi dipole antenna is not receiving much signal and the long-range one is, there's not much to interfere :). What is your opinion about this? How can be ensured that ISM standards are met?
It is not easy to connect multiple antennas because all antennas have to be 50 ohms. If you connect 2 of ehm they are only 25 ohms, etc. I also made a video which shows that the antenna is not very important for lora. If you have no line of sight, usually it dows not wôrk. If you have line of singt, it woks up to 700 km and more. Receiving with hi-gain antennas is alllowed. transmitting of course not.
10km transmission - this is by the guy whose github page is linked in the description. ua-cam.com/video/yCLb2eItDyE/v-deo.html PS: Interestingly, I was just watching that video just before this one.
Helou, very good video, If You Have Andreas this one E32-433T30D Lora Long Range UART SX1278 433mhz 1W, please check them and make test video for us, thank you, Andrzej.
First of all I want to thank you for your work and enlightening me and I would like to give you an interesting topic when it comes to long range communication. I came across this doc yesterday dl.acm.org/citation.cfm?id=3345436&preflayout=flat For IoT devices this seems excellent and I am really looking forward to see an actual implementation and maybe even test it myself, maybe something for you to look at as well?
Thank you for the link. I read the paper. Interesting idea. For me it seams like a niche product. On low data rates it easily could be replaced by LoRa with much better link budget. I also would transmit voltage from time to time to solve the Problemorten knowing if the device has no power.
I think it was something about the RED colored board. Apparently that is the color of communists. I am unclear whether communists have special snowflake status in Sweden. ...or maybe ant-communists get offended at the color. You'd have to ask someone more familiar with Sweden.
@@SteveWrightNZ I know. I don't care about other words. But his "develOpment" is just horrible. And if he learned somehow to do not pronounce "WiFi" as "wify" so he can learn to pronounce correctly the word "development" as well.
If we learn foreign language, we will never be able to pronounce like natives. Furthermore our mother tongue affects any new language we learn. He is Swiss.. He speaks some words in German accent, its obvious and ok. Language is mode of communication, if he has managed to communicate what he wants to... then purpose is solved. So focus should be in knowledge he is sharing...FREE for us. If legs n ears hurt of those who don't like few words.. they should put ear buds n rest ;). Great job Andreas... keep going.
In my experience, rain and fog do attenuate wifi signals quite a lot. Both wifi and microwave ovens use frequencies around 2.4 GHz. Maybe that is the clue? Microwave ovens heat the water in food, so water must absorb radio energy very well at that frequency.
My actual experience as a wireless ISP is that your suggestion is not correct.
I have to admit I have found Rain and Fog to affect WiFi in general, but not to a huge extent at 2.4GHz. Mainly in higher frequencies.
@@EsotericArctos I run 2.4 and 5.8GHz long range outdoor networks, and I've never seen even torrential rain cause any problems.
@@SteveWrightNZ If you designed your pathways with good RX\TX and they don't failed in rain, that's not empirical evidence that H20 molecules don't absorb 2.4Ghz RF. Because they do, therefore 2.4Ghz is attenuated, that doesn't mean your link will just drop. RSSI values just become lower.
My experience is that I have been using a flat panel wifi antenna to connect to a free public hotspot in a building some distance from my flat. At the best of times the connection can be a little slow but useable. In rain and fog it does not work at all.
Don't listen to those who seek to control your language. The intent behind the words ought to be important.
6:40 When considering the Fresnel zone this location is line of sight (light) but still not good for RF communication with trees and power lines inside the Fresnel zone.
And the helix antenna is circular polarity and will have significant polarization loss against a vertically polarized antenna.
You are right about both facts. So far I never used circular polarized antennas. I have to investigate a little more into this matter.
@@AndreasSpiessYou should be lost at least -3DB for using a circularly polarized antenna with a vertical antenna. I would recommend you to use a parabola antenna to get a higher gain.
@@AndreasSpiess I noticed you running cross-polarized antennas in your LoRaWAN distance tests starting with your gateway having a antenna that was 10° off vertical. This is something to avoid that is emphasized in the ARRL's educational literature as you'll lose 20dB when you use orthogonally polarized antennae.
www.mtiwe.com/?CategoryID=353&ArticleID=163
@@AkawichPonIn The circular polarized is actually not a bad choice. Just because it attenuates any linear polarized signals (or noise) by 3dB or more. And most noise, WiFi and Bluetooth is linear polarized. But of course you need the "partner" to be polarized in the same twist.
73 de LA8BKA
Follow my prior comment :
Wind usually associate with rain but fog. Antenna set in vibration in windy day, rain or shine, can make matter worse, with unwanted amplitude modulation that convoluting the wanted signal by a vibration magnitude and rate.
I agree with other commentator that flat antenna in video has feed port point sideways but downward. Can contribute 3 to 20dB polar mismatch loss to a linear antenna at the far end.
Thank you for your information!
Attempting to obtain useful WiFi service from home to town. Approx 2 miles. Lots of useful information for me in this video. Thank You Sir !
Should be possible.
Nicely done! That was a lot of work. Long range mode is a little disappointing, I was hoping for better. Well, these things advance in small steps. Thanks for sharing your results.
Sometimes also less than expected results are interesting because maybe it saves time.
Weather is a problem f of water is 2.4 GHz, so trees and rain/for are a big no :) also try pringles and yagi antenna.
Back in a days, around 16 years ago we manage to make stabile links with WiFi antenna made with satellite dish and yagi inside dish, we manage to reach 5-6 km in city and more than 30 km outside urban areas with Ateros chips since you can go a little outside regular WiFi freq. :) not so legal but it works :)
Thank you for your info. Of course I also had some „outside legal“ ideas;-)
This channel is wonderful
Thank you!
Wow nullbyte watching you
nullbyte your wonderful, thanks for teaching me so much
Your tool basket had two items missing, a flask of coffee and a Toblerone! Bob
You are right. Or a beer in summer!
I think you can improve the RSSI values if you use the same polarization in both transmitting and receiving antennas. I noticed that the panel antenna on the pole is using vertical polarization in contrary to the panel antenna inside the car which is using horizontal.
yup theres atleast a 3dB loss there ... RX and TX antennas should ideally be identical, both in dimensions and orientation..mixing horizontal with vertical and circular is very bad practice!..(even upto 30dB loss when mixing circular with horizontal or vertical)
@WacKEDmaN Are you sure about the 30 dB? I also had 3 dB in mind if polarization does not match.
@@AndreasSpiess 3dB is the loss from circular to linear. Linear Vertical to horizontal losses are greater. see www.antenna-theory.com/basics/polarization.php
@AndreasSpiess if you have a polarization mismatch of 90 (270) degrees in theory, you will have infinite losses, in practice is between 25dB and 30dB.
3dB losses is if mismatch is 45 (135, 225, 315) degress or if you use combination of linear and circular polarizated antenna.
"Unoficially sponsored by Swiss Tourism Office" ha ha. Excellent Mr. Spiess.
I did not see any cash :-(
By the way, may I suggest an alternative to the box? Blue Ikea bags are cheap, robust and lightweight, and once folded takes no space. When I worked as a field technician used it to transport up to 15 Kg. Can be handled using only one hand or carried in the shoulder. And in several occasions used them as a cover under the rain (they are waterproof).
Patch Antennas were not located correctly! This can be seen on video 7:45 and 6:55. The fact is that the patch antennas have a clear vertical or horizontal polarization. The spiral antenna has circular polarization. Therefore, for a spiral antenna, it does not matter what position it is in. For the Antenna patch, it is important that the cable goes down both on the transmitting antenna and on the receiving antenna.
I wondered which polarization the patch antennas have. Now I know. Thank you. AFAIK the loss of a wrong polarization is 3dB.
Just because the patch antennas appear to exist in two dimensions, it does not mean that they exhibit only linear polarizations. Patch antennas can be fed in a manner that produces circular polarization. If a single patch is fed from the side it is usually linear. If fed into the patch directly to a point inside the perimeter it can produce circular polarization. Many panel antennas are actually 2-4 patches which may individually be linear polarized but phased to produce circular pol.
Nice Video Andreas, but i think youre missing a major key to antennas...Polarization... youre mixing horizontal with both vertical and circular polarization... there can be upto 30dB loss between horizontal/vertical to circular...and about 3dB loss between horizontal and vertical...you should be using the same antenna (dimensions and polarization) on both the RX and TX sides
You are right. I did not consider polarization. I was not aware of the 30 dB. I was aware of the 3 dB between horizontal and vertical. But with all my tests I was not able to see big differences. If circular is so different I have to look into it. Also which polarization a panel antenna has
+1
I came down here to say this too. I think H-V cross polarization is a 20dB loss though. I think circular to linear is 3dB.
THanks Andreas. I really loved these last 2 videos and hope you do more follow-up.
We will see. I want to keep the channel open for different topics.
I have definitely noticed that the rain will not allow my esp8266 to send out the temperature from my chicken coop which is a good distance form my access point. Great video, as always very interesting!
Good to know. Thank you!
Another great video. I look forward to the "Mystery" video 😊
Not planned yet :-(
@@AndreasSpiess I will be looking forward to whatever comes next then 😊
We have ancient castles, they are called White Castles and are not in nice places. Tasty burgers!
it has been said before, dear Mr.Andreas is an amazing MADLAD!
Thank you!
Bravo! Such a great series of tests that for someone who knows little about radio and antennas but who finds the concept of action at a distance fascinating, were both useful and interesting. I have experimented with a commercial Yaggi antenna to connect the IP camera in the stable where i have my pony with my home wifi over a short distance of about 25 m, but although I had a little success it was not reliable, but I have managed to get a connection via the main cable with suitable devices and have given up on the Yaggi for now. However, I may revisit it as I have cabins at over 100 m that it would be useful to have wifi in. Just have to be motivated when i have time, the former easy, the latter not so. Thanks for sharing!
We all have 24h. The rest is priorities ;-)
This info and your experiment results will be very helpful to my degree's project thank you very much bro!
Glad it was helpful!
Swiss humor detected 3:43
I thought it was at 5:11 ;)
@@zmeygavrilych I think it was at both points 😊
Can we get a sensor for that?
The sensor is the viewer's comments. Always nice to read!
From an 'easy usage' point of view, it would be nice if they came pre calibrated. But as a viewer, no way am I submitting myself to calibration. I'm also glad they come in different pin configs too. 😁
Z=140xC/Lambda
Now, to get a standing wave axial type helical antenna we want C=lambda.
Which means were pretty much stuck with a 140ohm antenna. Now i don't how how it will affect beam forming or matching but using three perfect helical antenna with a matched 50ohm cable will give 140/3 roughly 50 ohm to get work done.
You have to adapt it to 50 ohms before the cable. It is done by the small triangular copper plate. I did not look into how it works.
Thanks for the video, waiting for next Sunday.
The next video is already nearly finished...
A place for everything, and everything in it's place. All Hail the Kingdom of Tidy and Just So !
??
Hello! Really like your videos. But you need to do something with the microphone cable, probably change it to shielded, when you watch your video in the headphones in the left channel, you can constantly hear background noise from the computer or something else. Thanks for the videos!
Gruezi. What do you think of the crude methods to add an external antenna to an ESP devboard v1 that only has a PCB antenna? Is there any chance to tinker with it such that we can match the impedance properly?
O would not try it unless you are good in RF design and have the necessary instrument because you can buy boards with antenna connectors.
Microwave oven also uses the same frequency, thus we can imply, water absorbs 2.4ghz quite well
You are right with the microwave. But other viewers reported different results with fog.
Could you show us the upload/download speeds (bps) at each distance? would be pretty cool to see.
I use an outdoor square type 2.4 GHz patch antenna for regular wifi to get it from remote router. I am always surprised that it works just as well even if there is torrential heavy rain or snow storm. The thing that has effected the signal the most was a heavy dew on tree leaves when the sun is at a low angle when coming up in the morning. But soon as the sun rises higher the wifi signal would come back okay. There are some hams in town near here using Aredn Mesh firmware in routers that are capable . On the ham bands certain frequencies are in standard wifi ranges so it allows the use of much higher power if someone wants to. I haven't gotten around to trying it out yet.
I can imagine that wet leaves are a reasonable ground quite high in the air. But good to know that fog is no problem. And I also read about these mesh networks, but never tried it myself.
Hi, can i ask one question Herr Spiess? I'm searching for some kind of power on reset device for esp8266, so if my solar weatherstation falls out because the overnight drained battery, when reaches again safe voltages it resets the esp! Thanks
You can search for voltage monitor IC (e.g. TPS3839) These keep the reset pin low as long as not enough voltage is available.
there is a great parametric design of a helicalantenna on thingyverse. using it for 5.8ghz video and outperforms any antennas I have bought that advertise same specs and is even quite rigid (the death of my self build helicals with cardboard was always because i threw them in a backpack and the copper wire deformed. not so with the design from thingyverse)
Sounds interesting. Do you have a link?
@@AndreasSpiess hi andreas, sure! its thingiverse.com/thing:2497461
Thank you!
Patch antenna (esp32 has it too) have linear polarisation but Helix is circular polarized. It is at least 3 db loss.
You are right. It was ok for me in this situation. Next time I probably build two helical ;-)
you are a real swiss genius!
Thank you!
Interesting as always 👍
Great video as always
Thanks for sharing 👍😀
You are welcome!
Egypt has great weather to experiments we tried at 5km in sight also !!
Of course, you have good weather! Maybe a little hor for me ;-)
Did it work? Did you achieve a 5km range?
Question: Does usable range imply both Signal from Site A can be received at Site B AND that it can receive signal from devices at Site B trying to communicate back to Site A?
I moved to the beach recently. I’d like to extend WiFi coverage approximately 250 feet to the beach . I do have direct LOS from second story of house to desired area of beach about 250 feet. I’d like 5gig coverage for iPhone and laptops.
If a long range Access Point states its service is usable at 300 METERS, 1) that seems more than enough and 2) does that imply that Iphone and Laptop device's WiFi signal can be received by that LR Access Point?
I strongly suggest watching this channel: ua-cam.com/channels/HqwzhcFOsoFFh33Uy8rAgQ.html He has plenty of stuff for your use case.
Your patch antenna in your test was facing downwards slightly , did you check radiation polarisation?
I saw that too. Bad mounting and some wind. The opening still should have been enough. For sure I lost a dB or so.
Is that possible to load all channels in 2.4 Ghz with ESP32 or 8266? To block bluetooth boom boxes in area for example.
Good fun Andreas!
Yes. Better weather would have increased it a little ;-)
@@AndreasSpiess It's always an adventure in the rain! :)
Thanks for part 2 Andreas!
You are welcome!
aumentou cerca de 10x o alcance original, aprovado.
Thank you!
Servus! Du, was ist mit den 2,4 GHz Lora Modulen geworden ? Das wäre ein Interresantes Thema, auch für Datenübertragung möglich ?
Schaue immer gerne wieder rein ;)
Datenübertragung ist sicher möglich mit diesen Modulen. Im Moment liegen sie immer noch in einer Box...
@@AndreasSpiess Es gäbe auch einen Sateliten (21.07 Launchdate) der 2.4GHz Lora Überträgt. Ich denke aber, das die Übertragung eher schwierig sein kann.
Ich finde deine Beiträge immer Ideenreich. DANKE mach weiter so ^^ ich weiss was das für ne hacke ist
Wir haben ja bereits einen Satelliten der auf 2.4 GHz (und 10GHz) arbeitet. Er ist geostationär und heisst QO-100. Du findest Videos wo ich eine Bodenstation gebaut habe...
Hi Andreas thanks for the great video as usual! If I'm not mistaken, you didn't yet investigate further the difference between your homemade antenna and the commercial one? In case I am incorrect, can you please provide the link to this "mystery video"? Thank you! :-)
I did no further work on the topic
@@AndreasSpiess Thanks for answering :-) I hope you will eventually find the time and/or interest to revisit this, it's very interesting in my opinion!
Hi Andreas. Did you care about the antenna polarization ? If your antennas are not with the good one there are big losses. As example: using two different linear polarization, there is 20dB of attenuation. As you use circular polarization, and if I remember my radioamateur experience, you must use one right hand and one left hand polarization. In an other way, it is not because an antenna has a good VSWR proove that is a good antenna (see VSWR with a dummy load). Hope this could help. regards F1SLU
You are right. I know about polarization, but never exprienced huge losses or wins on these high frequencies. And very often you cannot match porarization if the devices move (e.g. smartphones). I always thought the loss between horizontal and vertical polarization is 3dB. But I did no research.
Andreas Spiess
Theoretically, line of sight reflection free polarization mismatch of perfectly linear polarized antennas can be infinite loss and not 3dB.
Practically antenna system imperfection, imperfect linear polarized and stray reflectors may contribute cross polarizations allows an infinite loss to be finite loss.
A polarization mismatch link between linear and circular antennas in free space is expected to be -3dB.
@@AndreasSpiess It's 20dB. between circular and linear it's 3 (or 6 I do not remember !) dB
I am new to projects like this. I dream about making a portable transmitter/receiver for the common signal types like cellular, GPS, WiFi, bluetooth ANT+ and wonder what it would look like to make the form factor ideal for the antennas and portability. My thought is that it might be a good experiment to consider tethering various devices from such an antenna hub based on the contexts that you would use them instead of trying to continue to pretend that cellphones are good for everything. I could use advice on what direction to head to get the supplies and skills I need. Thank you for your excellent videos.
Maybe you start with one after the other? This is a huge project.
Very interesting... I look forward to your further investigations. I haven't really played about with antenna construction much since the CB days, which being 27Mhz involved somewhat larger (impractical) engineering!
I wouldn't worry about political correctness, it's gone mad. People who just hear words but ignore context are just revealing their own inner issues.
Thomas Sanladerer, the 3D printing guy, was stumbling all over this on a video about SPI, and the meaning of the MISO and MOSI acronyms, causing much amusement in the comments.
Yea, 27MHz antennas are big! This microwave stuff is much handier...
Was he talking about sketches called 'master' and 'slave'?
Why is the green color of the PCB important? Are other color PCBs made from a different material?
Think if it would have been black ;-)
Is there any chance of producing a comparison of commercially available stub and whip antennas?
I remember from earlier videos that some Chinese antennas were tuned to the wrong frequency and one or two were OK on 2.4GHz.
I need to mount some ESPs, via uFL to SMA, in metal boxes and I need to find usable antennas for them.
Thanks
The dealers on Aliexpress change their suppliers quite often. So it would make no sense. The only thing you can do is measure yourself. Or by from trusted suppliers. Sometimes even two antennas of the same packet are different.
Make sure to point the antenna directly at your head while transmitting. Nothing bad will happen.
You are right.
Did you take the beam width of the antennas into account ? I noticed that the antennas are dangling from the mast. If the beam width only is a few degrees it makes a lot of difference.
I guess the beam width is about 30 degrees. Have a look at the radiation pattern polar plot: www.comsol.com/blogs/analyzing-operating-mode-options-for-helical-antennas/
I agree my mounting was not ideal and I lost a dB or so due to that fact.
At 6:40 when you point antenna at your house, there are some power lines in the way. Do you think those decrease or block the signal?
I do not think so. They are only a very small obstacle.
Is not correct, because helix antenna have circular polarization, but patch antenna v-h. That's mean 6 db loss for helix, but thus helix independent for source orientation. Caution, helix create interference for both polarization v and h at the same time.
You are right about the loss between vertical and circular antennas. I do know which polarization my patch antenna has. My POTY 2.4GHz patch antenna, for example, is circularly polarized.
Short question. If I have an esp32 with an MQTT client with LR configured, is there an easy way to get it to an MQTT server in the cloud. The esp32 access point will be configured in LR mode also. So the esp32 LR appears to form an isolated island. It would seem to require a Bluetooth or serial link to another esp32 in normal mode. Is there a better way
I did not look into using a ESP32 as a bridge. If you look at the sketches I used you see that the master first connects to a regular AP. So it should be possible to use this one as a bridge.My topic was more the LR mode.
I think the mode comparison was a little unfair by transmitting using different modules, cables and antennas. Interesting results anyway!
There was less difference than you think. The transmitters were the same modules. The receiving s ich de was completely the same as I changed the Sketch f oh r the different Tests. The transmitting antennas were different.
Ok, got it!
Hi Andreas, you have lots of experience with ESP32. My ESP32 disconnects irregularly from wifi within 1-2 days always. Did u encounter this issue? What it could be? Many thanks!
Unfortunately I cannot do remote debugging. Especially not for sporadic errors :-(
@@AndreasSpiess Hi I know u cannot debug just was curious if you had this issue with yours esps.
No.
anyone know how to fix a black screen esp8266?
Hi do you know any solution for transmitting and receiving data low power? eg temperatur data sending and receiver both with a couple of aa batteries? nrf24, rfm95..they all need too much energy in rx mode. I'm searching for over an year now..
LoraWAN, ZigBee, Z-Wave
@max things: DerpyDoom is right
Really in RX mode and battery powered? As my searching there seems no other solution than a ook receiver. All the chinese stuff, wirelss door bells, thermometers..they all worked with simple ook receivers and many many month with just two mignon cells
I think the effort to reduce the use of the possibly offensive terms "Master" and "Slave" is mostly centered around IS orgs in countries with a fairly recent histories of a race based slave trade... i.e. the United States. I know that my employer has done their best to reduce the use of the terms and, frankly, I don't think any of us really care. It's not that hard to use alternative terms like Server/client or Primary/Secondary, whatever... and if it makes one or two people I work with feel a bit more comfortable, why not? I'm in a mixed race family and don't really care, but maybe it annoys someone else?
Cool. But I just sent a first Hello World message using a NB-IOT network. No need for big antenna's. T-Mobile offers a free sim card to play around with for a year. Maybe you can do a vid about these too.
If they would start it here for sure would cover it.
@@AndreasSpiess Are you suggesting your area isn't covered yet? I expect my nb-iot device to work if I would bring it over there and plug a battery in. A search on google tells me that Swisscom has completed rollout in Switzerland as per June 2019. Not sure if you can get a free sim to play with.
www.digitalkeys.io/nb-iot-network
documents.swisscom.com/product/filestore/lib/7247d9ff-14e6-408a-9982-c0589b688912/brosch%C3%BCre_connectivity-en.pdf (page 8)
I have a colleague who is in close contact with Swisscom to get a module and a SIM card. Unfortunately, the project is shifted and shifted...
3:50 LOL Andreas hahahahaha these jokes are hilarious xD
Thank you!
Hii great video. But I have some different issue. I'm getting exemption (9) and board resets. But I don't want it to happen. It's not a big code but I don't want it to restart like that .. I tried adding delay to it but didn't worked.. please help me with this, can't find another person with this kind of depth in esp. Tq in advance..
Unfortunately I cannot do remote debugging :-(
@@AndreasSpiess tq for sparing your time.. love from India.
3:45
that's what she said! oh man, sorry i had to.
:-))
It's great news 👏👏👏👏👏
Thank you!
Hello Everybody! Do you think ESP32 LR or LoRA are good ideas to consider when i'll try to connect my apartament with my basement in multi-occpupied building? I live on 5th floor and basement is on -1. There are many, many layers of reinforced concrete between us :( Any ideass greatly appreciated! Cheers!
I think that WiFi is very unlikely to work at all.
I would try Powerline. Here you have at least a change to be successful. LoRa only transfers a few bits per seconds
@@AndreasSpiess Possible depends on the country? I think some countries may use 3-phase mains? So it may be hard to find a power outlet in the basement on the same phase as the apartment?
i bought a powerline (cheap) speed reduces with length of electrical cable. if u have ups/inverters, they cause additional interference. ofcourse, 3-phase wiring means it may not always be successful. best solution till now is to use cat 5/6 cable from the router and add an accesspoint at each floor (concrete has steel reinforcement which eats all the signals, so they don't travel across the floors). But in the case of cat cables, rats don't like them. so these cables need reinforcement (from rats)
@@dd0356 I have 3 phases in my apartment, although basement may be connected very separate way. It's 7-story building, with 8 apartaments on each floor :( My last chance is GSM as it works well even underground, but it's additional cost every month to pay pre-paid internet on simcard working there. Thank you for your responses. Cheers!
You can use the mode WiFi On. Or WiFi Off Than your esp can do iT,S Thing and is not in deep sleep. If ... Is true WiFi on and send data.
Thank you for the tip!
What is a jowl meter ?
It measures Energy used by devices.
Water abdorbs 2.4GHz
www1.lsbu.ac.uk/water/microwave_water.html
Airborne droplets will do transmission range no favours at all. 😕
It gets worse with salt spray... Not a problem in Switzerland but worth considering ocean-going or even coastal applications where one might like an RF bridge to a smsll island without Internet.
That is what I thought. Interesting to bring salt into the equation! Never thought about that.
Very interesting :-)
Thank you!
👍
Great video, however, not really sure what to think of it... longer is better, sometimes thicker is better... political incorrect sketches... Very confusing. One thing I'm sure of... size does matter !
For antennas, for sure. And I only talked about antennas in this video.
@@AndreasSpiess Antennas... what else ?!
Its all bout the girth
I thought not everybody can agree ;-)
Hi Andreas, I'm Marco from Bavaria. Thank you for your time and great tutorials. I know this video is related to WiFi transmission but since you are a great fan of LoRa, I'd like to ask you a specific antenna question there: To my knowledge, the ISM regulation in Europe is 14dBm (=25mW). I see a lot of dipole LoRa-antennas with a gain of around 2.1dBi. For a specific project, I'd like a gateway to be able to listen with a long-range antenna. There are a couple of YAGI antennas with gains of 11dBi or even 23dBi available and can be sourced from digikey:
www.digikey.de/products/de/rf-if-and-rfid/rf-antennas/875?k=yagi&k=&pkeyword=yagi&sv=0&pv1851=291672&pv1851=299188&sf=0&FV=-8%7C875%2C1850%7C417331%2C1850%7C417333&quantity=&ColumnSort=0&page=1&pageSize=25
Do you think it is possible to connect multiple antennas over one HF port on a LoRa gateway (like the ones from Dragino or RAK). I can imagine that the signals of two antennas could interfere on the one hand. On the other hand, if the 2.1dBi dipole antenna is not receiving much signal and the long-range one is, there's not much to interfere :). What is your opinion about this? How can be ensured that ISM standards are met?
It is not easy to connect multiple antennas because all antennas have to be 50 ohms. If you connect 2 of ehm they are only 25 ohms, etc. I also made a video which shows that the antenna is not very important for lora. If you have no line of sight, usually it dows not wôrk. If you have line of singt, it woks up to 700 km and more. Receiving with hi-gain antennas is alllowed. transmitting of course not.
3:40 that's what she said
:-)
10km transmission - this is by the guy whose github page is linked in the description.
ua-cam.com/video/yCLb2eItDyE/v-deo.html
PS: Interestingly, I was just watching that video just before this one.
I know this video. But I do not know where to get this antenna :-(
Helou, very good video, If You Have Andreas this one E32-433T30D Lora Long Range UART SX1278 433mhz 1W, please check them and make test video for us, thank you, Andrzej.
1W is probably a little too much for UA-cam. I have to stay legal here :-(
First of all I want to thank you for your work and enlightening me and I would like to give you an interesting topic when it comes to long range communication.
I came across this doc yesterday dl.acm.org/citation.cfm?id=3345436&preflayout=flat
For IoT devices this seems excellent and I am really looking forward to see an actual implementation and maybe even test it myself, maybe something for you to look at as well?
Thank you for the link. I read the paper. Interesting idea. For me it seams like a niche product. On low data rates it easily could be replaced by LoRa with much better link budget. I also would transmit voltage from time to time to solve the Problemorten knowing if the device has no power.
5:20 Screw PCness!
That was a joke ;-) (Maybe not a good one)
@@AndreasSpiess Oh. It went over my head then. Sorry.
The political correctness bit was funny
The mysteri is a bad execution of the diy antenna to solve swr with this trick
I do not get your point. Maybe you explain it differently?
MANDA EM LÍNGUA PORTUGUESA
Unfortunately, I do not speak Portuguese
3:56 hahahahaaha
:-)
Not Politically correct? Was this a joke I missed?
I think it was something about the RED colored board. Apparently that is the color of communists. I am unclear whether communists have special snowflake status in Sweden. ...or maybe ant-communists get offended at the color. You'd have to ask someone more familiar with Sweden.
sketch is called master and slave
Please stop to pronounce the word "development" like that. It hurts my ears.
Lots of his words are wrong. People who matter don't care about it at all.
@@SteveWrightNZ I know. I don't care about other words. But his "develOpment" is just horrible. And if he learned somehow to do not pronounce "WiFi" as "wify" so he can learn to pronounce correctly the word "development" as well.
@@UnCoolDad According to this stupid "logic" ANY pronunciation is absolutely fine.
If we learn foreign language, we will never be able to pronounce like natives. Furthermore our mother tongue affects any new language we learn. He is Swiss.. He speaks some words in German accent, its obvious and ok. Language is mode of communication, if he has managed to communicate what he wants to... then purpose is solved. So focus should be in knowledge he is sharing...FREE for us. If legs n ears hurt of those who don't like few words.. they should put ear buds n rest ;).
Great job Andreas... keep going.
@@Trident7235 ANY pronounciation IS fine. Go away. I like listening to Andreas, he's very relaxing and a nice fella, and you are not.
dont work
............................................................................................ets Jun 8 2016 00:22:57
rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:1
load:0x3fff0030,len:1344
load:0x40078000,len:13964
load:0x40080400,len:3600
entry 0x400805f0
Slave
Error = 0 , Mode LR OK!
...........................
This project is 6 years old. Maybe you find a newer one...
👍
:-)