[123919239]

Yes, IQ modulation / QAM.

I haven't studied the BladeRF layout, I can just tell about the Ettus USRP. There, the receive path looks like that:

[Antenna]---[ADL5380 Quadrature Demod]===[2x low-pass filters in parallel]===[2x ADC in parallel]

Then you have digital data that is fed to the FPGA.

[gsteinb88]

Yeah, the BladeRF uses an AD9361[1] as the transceiver, which features a pair of ADCs per channel, of which there are two (so, a total of 4 ADCs and 4 DACs in the package). It's got a bunch of other convenient features like built-in PLLs both LO and baseband.

[1]

[gsteinb88]

oops: [1] https://www.analog.com/en/products/ad9361.html