用于方向回溯天线的Costas环相位共轭电路设计

Design of Costas loop phase conjugate circuit for retrodirective antenna

为实现天线波束的实时自动对准即方向回溯,提出了一种基于Costas环的相位共轭电路,同时该相位共轭电路具有解调调制信号的能力,即实现全双工通信的能力。首先,利用改进的Costas环结构实现对调制信号的数据解调输出及载波恢复。然后,采用外差混频结构对已恢复的载波进行相位共轭,并以此作为发射载波进行信号调制输出,从而实现阵列天线波束向来波方向自动实时对准,即实现具有方向回溯能力的全双工通信。最后,通过仿真对该电路进行功能性验证。结果表明,该电路在不同输入载噪比条件下,实现了对四相相移键控调制信号的解调,相邻射频通道解调信号的同相叠加,相邻射频通道相干载波信号的相位差共轭,验证了该相位共轭电路的波束自跟踪和全双工通信能力。

In order to realize the real-time automatic antenna beam pointing,namely retrodirective,a kind of phase conjugate circuit based on Costas loop is put porword.Meanwhile,the phase conjugate circuit has the ability of demodulating the modulated signal,namely the ability to realize full-duplex communication.Firstly,the improved Costas loop structure is used to realize the data demodulation and carrier recovery of the modulated signal.Then,the phase conjugation of the recovered carrier is carried out by heterodyne mixing structure,and the signal is modulated and output as the transmitted carrier,so as to realize the automatic real-time pointing of the forward wave direction of the array antenna,that is,the full duplex communication with retrodirective ability is realized.Finally,the function of the circuit is verified by simulation.The results show that the quadrature phase shift keying modulation signal can be demodulated under different input carrier-to-noise ratios,and the demodulation signals of adjacent radio frequency channels are in phase superposition,and the phase difference conjugation of the coherent carrier signals of adjacent channels is verified,so the beam self-tracking and full-duplex communication ability of the phase conjugation circuit is verified.