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I am new to RFID hardware.

I am looking for RFID reader that could detect multiple passive tags in an only small range of 4-6 inches (~15 cm). Imagine we have about 8 objects with RFID tags on it and we move all these 8 objects into this small area, and the RFID reader detecting all of the tags.

Googling around, I found this, and that further leads me to several hardware. For example, the common MFRC522 and the PN532. But the range are 6 cm only, and the shopkeeper said it could actually be even as low as 1 cm and it is pretty much for 1 tag at a time, so these do not fit the bill.


Eventually, I found some more appropriate ones:

--> RFID Module - SM130 MIFARE

From the datasheet, this one has read distance of 9.5 cm only. (~24 cm) Also, I'm not sure about reading multiple tags.

This one seems like it fits the bill:

--> M6E Nano
Once you’ve started, this board will read EPCglobal Gen 2 tags (see Recommended Products) at up to 150 tags per second. Writing of tags is also possible at 80msec standard write. The board has adjustable power output from 0dBm to 27dBm, meaning that with the correct antenna you can read up to 16 feet (4.9m), or 1 to 2 feet (60 cm) with the onboard antenna.
...although the range is quite overkill and the price is quite high.

So does anybody know any hardware that fits the bill more appropriately? Or is the M6E Nano the best candidate here?

The RFID reader I required needs to be able to read up to 8 tags simultaneously in a 4-6 inches range only. Preferably, if it's cheaper than M6E Nano, it would be great. But if not, that's ok too.
An NANO-M6E Sparkfun reader is able to read multiple tags from a distance. A test just done read from a distance of 40 cm with the reader to be set to max read-power (27dbm). on 20dbm it handles around 15 cm. Of course this is also down to the quality of the tags and the position to the (on-board) antenna.(you can also connect an external antenna to improve the reading even more). It will require extra power however, a very stable 1A/5V. If powered only from a USB connector I can get a stable performance with a power around 5dbm. The tag needs to be nearly on-top of the reader in that case.