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I would like to create system which recognize products in store. What I want to use is RFID HF technology, because of it's perfect work range (1-2m is perfect for me). Unfornatelly every rfid reader compatible with raspberry pi 3 (which I found) is working in range of few cm.

Do you know any rfid hf module (with antenna or not) for raspberry 3 which would work in longer range (approximetely 1-2m)?

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This project on hackster.io outlines what appears to be a successful approach using a Cottonwood: Long Range UHF RFID reader with a Raspberry Pi 2 running Windows IoT. Per previous comments it's fairly expensive at $187 per unit - some googling suggests that that's going to be an unavoidable cost for this type of unit. The reader's specs list the effective range at 1-6m (likely only achievable with a fairly expensive antenna), which would fit your application, although it does come with some warnings to check that using it complies with your local radio regulations.

The tutorial is too involved to post in full, but the author gives a brief synopsis outlining the high level details:

This solution is comprised of two parts. An online web application that lets the user register their monitors and tags, and a Windows IoT Core Background Application, that is responsible for reading tags and sending the data to the cloud (Web Api service provided with the online web application).

Software assets that accompany the tutorial are currently hosted at Github:

  • I got one more question now. Do you know any HF reader (13.56MHz) with replaceable antenna? I would like to perform some tests regarding antenna power - reading range. – Maciej Treder Oct 14 '16 at 11:02
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I realize that I'm rather late to the party, but I do have an answer to the original question about HF (13.56 MHz) RFID. Unfortunately, the answer is no. I've experimented with a Feig MRM102 reader, which has an output power of 1.2 watts, and a carefully designed coupling loop about 150 by 250 mm. A fairly large commercially available tag, 40 mm square, will read at 350 mm. This far from the loop, magnetic field intensity drops with the cube of the distance from the loop. So, to double the range, you'll need something like eight times the power. A larger loop might be better, but then the inductance goes up and you need more power to get back to the same current and hence field intensity. To read at one or two meters, you'll need to spend a lot of money. My guess is that the claim of a 1 to 2 meter range comes from entry/exit surveillance systems where the coupling loop is five feet high and two feet wide and there is a 5-watt reader, like the LR1002, in the base.

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