NOEMA frequency coverage (all frequencies are in MHz). Top: receiver frequency coverage. Four IF (2 sidebands ×2 polarizations) are selected by the receiver. The IF processor uses a LO2 at 7744 MHz to split each IF in two basebands (Inner and Outer). Bottom: each baseband is split in 64 sub-bands that are 64 MHz wide after discarding the overlapped sub-band flanks. Four sub-bands (256 MHz) form a VDIF thread (see Sect. 2.4.3) and four threads are multiplexed on a stream to the recorder.