ESP8266 Community Forum

- Wed Nov 09, 2016 9:22 am #57879 So today I have made range test of sending TCP packets between 2 esp devices .
Unfortunately at distance of 90 meters the connection lost and no reconnect succeed.

The portable ESP8266 was powered on batteries ,
The environment was open air with houses around (means many other WiFi stations around ),
Was testing on radius not straight line .

1. On this video :

https://www.youtube.com/watch?v=ekSsi83-x8M&t=379s

The esp's connection was good for range around 1Km.

On this video :

http://www.electrodragon.com/product/es ... ifi-board/

The esp's connection was good for range around 400m.

Questions :

1. They used esp module 12F , I see it has little bigger built in antenna , can be that this the reason I got so low range ?

2. Is there is option to extend the built in antenna with 12E module ?

3. Is using batteries on the portable device reduce the range ?


I would like to hear any advice's for trying improving the range please,
Maybe I missed something with the circuit or anything else please.
Thanks !

- Wed Nov 09, 2016 10:27 am #57884 http://www.espressif.com/sites/default/ ... _guide.pdf

Layout is important. Espressif have been improving performance with each revision. Placement of the module is important. The way it is integrated into the final product. The radiation pattern is not clean. A few degrees can have a significant impact on reception. It just depends on how the final device was implemented.

The range tests you linked to do not indicate reliable operation. Ability to ping is not the same as transmitting larger quantities of data.

- Wed Nov 09, 2016 7:05 pm #57904

http://www.espressif.com/sites/default/files/esp-wroom-02_pcb_design_and_module_placement_guide.pdf

Layout is important. Espressif have been improving performance with each revision. Placement of the module is important. The way it is integrated into the final product. The radiation pattern is not clean. A few degrees can have a significant impact on reception. It just depends on how the final device was implemented.

The range tests you linked to do not indicate reliable operation. Ability to ping is not the same as transmitting larger quantities of data.

My problem is distance from clients to server....I used ESP8266 as server because tough it has longer range then home router (it has maybe but not enough).

Do you think the best solution for me is to use kind of Wi-Fi extender ?
For example :

TL-WA5210G: 0~2km
TL-WA7210N: 0~5km
TL-WA7510N: 0~5km
CPE210: 0~5km
CPE510: 0~15km+


Or I can some how achieve the same goal cheaper ?

- Wed Nov 09, 2016 8:59 pm #57908 I have some ESP07 that allow the use of an external antenna. That should give better range but I have not tried it yet. There is a new version ESP07S that might have better performance but I have not received them yet. The ESP07S has 4MB flash where the ESP07 only has 512K (or maybe 1MB, I forget).

When using an external antenna use only an antenna with a short cable. At these frequency cable loss is significant when you increase the length. The is cheap long cables sold out of China. Do not use it as it has very high loss and you would be better using the trace antenna on the board.

Mount the radios high above structures. Generally higher is better. Near the ground is poor.

There are higher gain antennas and that is an option but as I have said, use the shortest cable to connect it. Higher gain antennas are directional.