Coupled oscillators with shared bias current

This paper is on the study of double coupled oscillators, where two cross-coupled differential oscillators share the same bias current. Without external coupling, competition for bias current happens, and the one with a higher Q can grab most of the current, and the other one is starved to death. With external coupling, a beat pattern is generated and the beat frequency is strongly related to the value of the coupling circuit elements. These phenomena are investigated by experiment, circuit simulation, and theoretical analysis. The results agree with one another quite well.