フィードバック位相制御アンテナビームフォーミングの望まない安定状態の有無の検討

抄録

A feedback control system containing non-linearity can have plural steady states. One of the steady states must be the desired steady state, and the others can be undesired one. In this paper, the steady state analysis of the proposed feedback phase control system for antenna beamforming is described. The analysis shows that there are three groups of equilibrium points. One of them is a group of the desired steady state points, and the others are groups of unstable equilibrium points. An unstable equilibrium point is like a ball on a hilltop, and a small stimulus drops the ball down. The feedback control system is for radio receivers, and thermal noise takes a roll of the small stimulus. Therefore, the system cannot stay at the unstable equilibrium point and moves to the desired steady state.