The front inlet is the ramjet inlet, the second is scramjet inlet. They will not be both working at the same time for long. What will happen is you have the rocket booster stage which will accelerate the missile from stand still to a speed where the ramjet will start working, the booster is jettisoned and ramjet kicks in to accelerate the rocket to high supersonic speeds where scramjet will start working. Scramjet will then kicking in and push the speed higher still and the efficiency of ramjet will drop until it ceases to function and you have a hypersonic vessel traveling mainly by scramjet.am I reading the diagram correctly? I see separate subsonic and supersonic air intakes. There are those weird dimples on the shock cone of the CX-1 mockup. and the display that claims CX-1 has scramjet. hum...
This could allow both longer range and more flexible approach as the missile can fly high in scramjet mode to cover distance quickly and cover more distance at higher speeds, then when dropping low for final approach kick ramjet back in to ensure high speed final run where scramjet won't likely to work because of higher air resistance at near sea level altitude.
The dimples you see probably correspond to closed ramjet intakes if you try to translate this drawing to CX-1, while the ring opening that you see may be for scramjet.
Not only are the intakes separate but the combustion chambers for both is also separate. The ramjet combustion chamber is likely to not be working when scramjet flight takes over or at least not contributing to scramjet operation.