Communication via VOIP without PC/Laptop/Smartphone

Hello guys,
I have TP-Link MR 3020 with openWRT installed, i have an idea to make a communication device using just a router and a microcontroller such as arduino. the question is, is there any possibility to communicate using arduino via VoIP? as i know you need a device like a laptop or a smartphone to use voip to call each other.

i would like make a cheap communication device, i think that bring your own smartphone is not applicable in my project, and beside that you need to charge your smartphone.

Thanks in advance for your help, any advice would very appreciated.

what about a voip phone


a voip adapter for a standard phone

if you want clear speech... probably not.... it's difficult... almost too difficult....

you're basically looking at two ADC pins for AUDIO and the translation on the router....

alternatively, arduino can handle some basic "voice recognition".... which you could use to set a DIGITAL HIGH/LOW.... which a router could use to initiate a "scripted voip call"... the same can happen in the reverse direction.... i.e. to turn on a pump by pressing numbers on a remote phone...

that's the overview of what you have to work with.... off the top of my head....

a cheap wifi enabled handset is 1000 times easier with more functionality minus the GPIO's...

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my plan is to avoid using phone, but if thats the only way i'll consider it

Thanks for your answer

If you have a little patience, you can find mid-range to higher-end SIP desk phones from Cisco or Grandstream (or Siemens OpenStage) for under or around 10 EUR delivered on the used market. Depending on your choice, the initial setup might leave you with a few grey hairs, but you will be rewarded with a good quality phone and a decent feature set.

If you do insist on 'making it yourself', there are ESP32 derived options, like e.g., but you will get better results with a real SIP phone.

that is exactly what im afraid with this project.
Do you have a recommendation for a cheap wifi enabled handset? i need a low power device so i can use the device in a long term.

Thank you for your response:)))

The esp32-ADF seams feasible with my project, i'll look into it.

Correct me if im wrong, but a real SIP phone need a high power input.
is there a portable SIP Phone?? that have a battery in it

Thank you for your reply.

The big differences are ADC/DAC quality and CPU for signal processing.

Arduono, ESP32, and devices of that class, good luck with both.

Portable SIP phone for 802.11? Basically any old Android phone.


is there a way that by using only a openwrt installed router to call a device such as a laptop? so the communication happen between a router and a laptop.

Pretty much all android phones since around android 6 offer setting up VoIP/ SIP connections over WLAN, including the very cheapest ones (echo cancellation might not be ideal, but that will be even more of an issue for diy approaches). Economically speaking (especially if you include used options) it does not really make sense to build your own, as you can't compete with ease of use or audio quality.

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asterisk and a (compatible) usb soundcard might be what your thinking of... ( controlled over command line -> so that kind of blows any power benefit out the window )

i see,
so, if i have 2 openwrt installed router that have usb soundcard attached, the router can call each other??

sorry if i ask you very basic question, im new in this openwrt world

yes, one of my consideration is price in making this project. if that is the case, then i will use android phone.

Thank you very much for your response.

i agree,
android phone is my best option at the moment

Thank you for your response

So far here's my conclusion so far:

  1. make a DIY voip device would need a lot of work, and need a lot of money. i can use android phone instead.
  2. i can use my own router to make a call, i just need a usb soundcard.

my question is, can i use a router instead of android phone?? because mr3020 is very cheap in my city than an android phone, it will make my project a lot cheaper.

go with the phone... $40AUD / $30US would get something decent. ( second hand motoG first or second gen or similar age )