That's a diagram of a motorjet. The piston engine drives a compressor which compresses air into an expansion chamber where jet fuel is injected and ignited. From what I understand this is very wasteful of fuel and not as powerful as the turbojet. It was basically one step above a rocket boosted propeller fighter, where the prop is used 95% of the time and the rocket/motorjet used when needed. Both types were experimented with by the Soviets.
Another Soviet design was a prop fighter with two pulsejets at the wingtips. Pulsejets don't give a lot of power and they're noisy so you needed to keep them as far away from the pilot as possible, hence the wingtip layout.
Pulsejets were so simple that it could have been made long before the Wrights. Can you imagine a biplane with four pulsejets at the wingtips? It would look like a X-wing.