This device features two tuners and is supplied with two antennas. You'll have adapter0 and adapter1 in /dev/dvb, which you can use separately.
The "Diversity" option is a hardware based feature that allows for the device's two receivers to be configured in a combined use mode to achieve better reception on a single channel. The diversity feature of the DiBcom demodulators is currently not implemented in the Linux-DVB drivers, so only the dual tuner configuration is presently supported on such devices .
This device's USB ID is 2040:9580.
Making it work
You will need the dvb-usb-dib0700-1.10.fw firmware file in /lib/firmware or the relevant place for your distribution.
Support is present in the Linux kernel from version 2.6.24-rc1.
Just use Mercurial by following the How_to_install_DVB_device_drivers instructions.