DP0501 RTK GNSS (Tiny M8P)


DP0501 RTK GNSS (Tiny M8P) this gps has an external antenna sold saparately. May i know do i need to buy the optional antenna

And can you tell me the difference of the performance with and without the optional antenna


This RTK GPS does require an external antenna. It cannot work by itself, without any antenna.
Since this device is L1 compatible only I suggest you to have a look at here :

Although, it can also work with any L1/L2 multi band antenna (https://store-drotek.com/299-multi-band-gnss-antennas) and might be convenient for any future improvement of your setup by using the F9P RTK GPS family instead :