Phase controller and phase controlling method for antenna array, and communication apparatus using the same

A communication apparatus, comprising:

• a multi-phase signal generating circuit, providing K first frequency signals with K different first phases;
• L antennae, forming an antenna array;
• and
• a phase controller for the antenna array, connected between the multi-phase signal generating circuit and the L antennae, comprising:
• a determination circuit, determining a direction index of the antenna array, and calculating a phase index according to the direction index according to a congruence modulo equation;
• a switching box, connected to the determination circuit, selecting L first frequency signals with L different first phases among the K first frequency signals with the K different first phases according to the phase index, wherein L and K are integer larger than 1, and L is not larger than K;
• and
• a frequency synthesizing module, connected to the switching box, comprising L phase-coherent PLL frequency synthesizers for receiving the L first frequency signals with the L different first phases to generate L second frequency signals with L different second phases to the L antennae of the antenna array, wherein a second frequency of the second frequency signals is larger than a first frequency of the first frequency signals.

A phase controlling method for an antenna array, comprising:

• determining a direction index of the antenna array;
• calculating a phase index according to the direction index according to a congruence modulo equation;
• selecting L first frequency signals with L different first phases among K first frequency signals with K different first phases according to the phase index, wherein L and K are integer larger than 1, and L is not larger than K;
• and
• generating L second frequency signals with L different second phases to L of antennae of the antenna array according to the L first frequency signals with the L different first phases by using L phase-coherent PLL frequency synthesizers, wherein a second frequency of the second frequency signals is larger than a first frequency of the first frequency signals.