Zyxel NR5103: Suitable external antennas

Dear all

The NR5103 5G modem provides the option to use up to four external antennas through 4 TS9 connectors supporting 698-4200 MHz frequency.

I was now looking for suitable external antenna products. Unfortunately there is no list of compatible products via Zyxel channels. I would appreciate if anyone could point to suitable products compatible with the Zyxel NR5103 (incl. any suitable antennas products by Zyxel) to maximize reception.

I guess only a 4x4 Mimo external antenna makes any sense (i.e. 2 port solution not being sufficient)?

Many thanks! :-)

Kind regards, J.