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5

It's all about power. Passive RFID tags work by transmitting power from the transmitter to the tag (typically three orders of magnitude more than the data signal), and then communicating with the tag at various frequencies (13.56 MHz, 433 MHz, and 900 MHz band being the most common). The transceivers on these chips operate in the hundreds of µW range (...


4

The term that you are looking for is Anti collision. "In the context of RFID, anti-collision refers to different ways to keep radio waves from one device from interfering with radio waves from another device. RFID readers may make use of anti-collision algorithms to enable a single reader to read more than one tag in the reader's field". This is taken ...


2

Since the reader actually works on the serial interface you will probably need the communication protocol and that is usually something you can't easily reverse engineer, but if you plan on the first thing you need to do is get it to respond and react in some way. You will probably not get it to do so by just sending random data to it, since it will ...


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You could consider using image analysis with a camera positioned over the instrument tray as long as the instruments have distinctive enough shapes.


1

There are two challenges with using RFID tags, one of which has been covered in the comments. The tag, presumably, must be autoclavable. As these tools are metal, the presence of a metal plane so close to the tag will cause problems, or completely prevent operation of normal RFID chips. As a possible solution, you could use the RFID tags manufactured by ...


1

I'm pretty sure it does not depend explicitly on the type of device or hub depth on the other end. The reader sends out an electromgnetic field, which is used to power the chip inside the RFID card, and also to transmit data back to the device. (the card switches a load on and off, which results in variation of field strength over time. The reader detects ...


1

The range of a RFID reader with a (round) coil with diameter D is approximately D/sqrt(2). So you need a (round) coil with approximativ D=15cm to get more than 10cm reading distance. But as the inductance needs to be the same, you have to reduce the winding turns of the coil accordingly. How to? The total length of the wire of the new coil needs to stay the ...


1

No matter how long you search you will never be able to find pre made symbols and footprints for every imaginable part. Even if you find a symbol or footprint for your part somewhere you still need to check it for correctness. You mention in a comment above that you have trouble getting kicad to save your symbols and footprints. I have written up some ...


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SnapEDA has free KiCad libraries to download. You can search for the libraries you need and install them as you need them. DigiKey has a library of many common parts which are linked to their footprints. These can be nice because they have manufacturers, part numbers, and many other associations in their keywords. Mostly, though, you should be making your ...


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As defined by the ISO 11784/11785 standards, FDX-B is 134.2 kHz. FDX-A is 125 kHz.


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The info you you shown us here is just the basic data that a mifare tag gives out (the only relevant info is actually the serial number). But in a mifare tag, there is also an EEPROM zone (1kbytes) that can be configured with custom data, and the contents of this zone is not displayed here. This zone can also be configured with read and/or write protections ...


1

An RFID tag is just a MCU with a coil, outputting over a fixed frequency carrier wave. Some are passive, i.e. they harvest energy over the coil, while others are Active, with their own power source. There is nothing special about the RFID spec. So yes, it should provided with the right coil and programming.


1

You're unlikely to get a good distance reading from passive RFID tags required for trilateration. Passive tags get their transmit energy from the reader. To get a distance in wireless systems you typically look at how much power you receive from a known transmitter, in this case you have to guess at how much power the tag got and then reflected back and ...


1

Visit and join over at OpenCores. There is a section there of various types of CPU cores that can be plugged into an FPGA design.


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