RFID Reader 125Khz Module

I have this RFID Reader Module with Radio Frequency of 125kHz
Operating Voltage: 5 Volts, 9V average(8 to 15V)
Operating Current: 100mAh

The current range is approximately 3 inches. We are planning to increase its range up to 6 inches.

We have two options, but we are not confident with both of them.

The first one is that we will change the antenna, but will it also change the frequency that will be read by the module? are we going to change our RFID tags? and could it really change the range of the antenna?

Second, we are planning to attach an amplifier in between the antenna and the module.

Thank you!!!

Attached is the manual of the RFID Reader Module.

From the schematic on the datasheet, changing the antenna won't change the frequency which is fixed by the MCU.

Another point to consider is:
Will the reflected RF signal from the RFID card be stronger, or not, by increasing the RF power at the antenna of the RFID reader?

There seems to be a misunderstanding of how these RFID cards work, not only in this posting but others too. Increasing the RF output power will not necessarily increase the range, it will extend how far the modules signal will reach but not that of the card/tag it's talking to. They work by 1. Powering the internal circuit of the card 2. Sending commands/data to it and 3. Allowing the card/tag to modulate the loading on the antenna. The loading is then analyzed by the module to recover the data from the card/tag. If you simply add a power amplifier it will only increase the range of steps 1 and 2 but it will almost certainly prevent step 3 from happening at all.

You can experiment with physically larger antennas, it will help to some extent but you have to keep them tuned to 125KHz. In most modules there will be some status indication that alerts you to an antenna problem. The actual 125KHz frequency is determined by the module, not the antenna and is of course fixed in the card/tag anyway.

Brian.

Thank you for replying with my post, we have made a larger antenna and with that, we observed that it has increased its range Though minimal, its an improvement. Thank you for your advices!