Extend Adafruit PN532 range

Hi everybody :slight_smile:

I'm new in this world, and i would ask you some informations and advices for my project (i hope this is the right section, if it's not, excuse me :slight_smile: ):
i want to use a passive rfid system as a sensor, in which the reader has to read the tag and communicates this to the microcontroller. I've searched some specifics, and i'm interested to the Adafruit PN532.

I know that his range is up to 10 cm, but i need a range 3 time bigger (so 30 cm).
My (big) problem is the cost: my budget for whole system is at most 100-120 €, so i need an rfid reader very cheaper.

So, my questions are:

  • is possible to extend the range of Adafruit PN532? If yes, could you tell me (or simply advice me) how to do that?
  • If is not possible to extend the range, could you tell me some rfid modulo (cheaper), to connect to some microcontroller, with a range of about 30cm?

The most important specifics for my project are:

  • range of coverage of about 30cm;
  • 100-120 € for rfid reader, some tags and a microcontroller (any kind);
  • any frequancy range (LF, Hf of UHF), just it doesn't exceed the budget range.

Thank you for your answers!!!!
Alex

is possible to extend the range of Adafruit PN532? If yes, could you tell me (or simply advice me) how to do that?

Theoretically yes. Build a better antenna. But in reality: forget it. Antenna engineering is kind of magical and even with an almost perfect antenna you might not come into the range you’re targeting.

If is not possible to extend the range, could you tell me some rfid modulo (cheaper), to connect to some microcontroller, with a range of about 30cm?

Is the range complete line of sight? Or are there any materials in between the antenna and RFID (body, textile, plastic, etc.)?
Tell us more about your project, maybe we find an alternative solution.

Hi pylon!
Thanks for your help!!!

Is the range complete line of sight? Or are there any materials in between the antenna and RFID (body, textile, plastic, etc.)?
Tell us more about your project, maybe we find an alternative solution.

For my project, i need an rfid system with one fixed reader and some passive tags (about 10 to 30) for a access control system. It’s like a reader on a door and i want to count the number of crossing.
I’ve seen a lot of NFC modules, but for my project is too reductive.

So, to answer your question, the range that i’ve written is the complete line of sight. :slight_smile:
Thanks a lot!!
Alex

So, to answer your question, the range that i've written is the complete line of sight.

In an access control system I don't see the need for 30cm if you have line of sight. That mean the tags have to be hold against the reader anyway. A tag in the pocket has no line of sight! For access control systems you can use readers with a range of 3cm without a problem.

If you want to have a system where people can simply have their tags in the pocket or in a bag you need a more powerful transceiver which most probably will break your budget. It might be time to make a compromise.

I’m sorry, i didn’t explain well, excuse me :slight_smile:
The system that i have in mind is composed with a tags, with no obstacles, like a bracelet on people’s wrist, so when a person pass through the door (one by one), the reader can read the tag with a complete Line of sight, that i need of about 20/30 cm.
Thank you and excuse me again :slight_smile:
Alex

I have found this reader, the ID-20LA from ID Innovations, whose range is about 16-20cm (a compromise that i can accept):

Could it be good for my project? i read that has a different distance between pins, but i could adapt it with the Sparkfun board:

What do you think about it?

Moreover, i thoght to use, as microcontroller, an Arduino UNO R3, so:

  • Could Arduino UNO R3 be good for my purpose?
  • Is the ID-20 simple to connect and to configure with the Arduino UNO?

I did't explain my idea well (sorry again for that), so i summarize it:
I want to create an RFID access control system where, supposing to apply it on a door crossed by people, one by one, the system reads the tags (located above people, in sight to the reader) at a maximum distance of 20/30 cm.
Thanks a lot!
Alex

This reader has maximum range of about 18cm which is below your spec and won't be reached in most situations. In reality you probably will see something around 8-10cm. But try it in your environment and see if it matches. I still think that for an access control system it's feasible for people to hold the tag directly onto the reader to open the door (or whatever you want to control the access to).