Using EM4095 - Githubissues

LieBtrau / arduino-as3933

Arduino interface to the AS3933 3D LF wakeup receiver

GNU General Public License v3.0

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Using EM4095 #9

Closed bakosaleima closed 2 years ago

bakosaleima commented 2 years ago

In according to you, could the EM4095 be used instead of AS3933 as wake up signal for rfid application? And what about RDM6300

LieBtrau commented 2 years ago

Hi Bakosaleima, The EM4095 and RDM6300 are RFID-readers. These readers generate an LF-field and require lots of power to do so. The AS3933 behaves more like an RFID-tag. It requires the energy of the RFID-reader to wakeup.
So : no, the EM4095 and RDM6300 can not be used instead of the AS3933.

bakosaleima commented 2 years ago

thank you for the quick answer, I didn't undestand whether the rdm6300 couldn't be used because of range or hardware incompatibilities? The signal is on 125khz both rdm and as39 work on the same frequency, I don't care about power or range, so theoretically could the rdm receive the signal as it is and resend it?

LieBtrau commented 2 years ago

You could use the RDM6300 or EM4095 to wake-up an AS3933.

I stopped developing the AS3933 because I think Bluetooth Low Energy (BLE) is a better fit for most applications:

AS3933 is expensive
AS3933 range is limited
AS3933 requires fairly large (and expensive) antenna
AS3933 itself might be low-power, but it requires a high power transmitter.
AS3933 is RX only. It can't send data back to the base station.
AS3933 requires an external microcontroller, which further adds to cost and PCB-area.
AS3933 is not secure. Any device that generates the correct waveform will wake it up.

All these are disadvantages that a BLE-device (e.g. nRF52840) doesn't have and it doesn't consume much more power.

If your application really requires RFID (e.g. for scanning items as they pass through a gate), you're probably better off with 13.56MHz vicinity cards/ICs (ISO/IEC 15693).

bakosaleima commented 2 years ago

Wow, such a precise answer thank you so much! Anyway I would like to complete my work with rfid 125khz. My final question is this: will the rdm6300 work as well as as3933 in reading/sending wake up signal? If no do you know of any other arduino compatible device that can solve my problem?

LieBtrau commented 2 years ago

You could try to use the RDM6300 to generate the 125kHz field to wake up the AS3933. As the RDM6300 probably can't modulate the LF-field, you can't use the MSK-pattern matching of the AS3933. The AS3933 will wake-up when it receives any 125kHz signal, probably leading to a lot of false wake-up events.