Method for automatically adjusting tunable passive antennas, and automatically tunable antenna array using this method

An automatically tunable antenna array having m user ports, where m is an integer greater than or equal to 2, the m user ports presenting, at a given frequency, an impedance matrix referred to as the impedance matrix presented by the user ports, the automatically tunable antenna array comprising:

• n tunable passive antennas, where n is an integer greater than or equal to 2, each of the n tunable passive antennas comprising at least one antenna control device, one or more characteristics of said each of the n tunable passive antennas being controlled using said at least one antenna control device, said at least one antenna control device having at least one parameter having an influence on said one or more characteristics, said at least one parameter being adjustable by electrical means;
• at least m sensing units, each of the sensing units delivering one or more sensing unit output signals, each of the sensing unit output signals being mainly determined by one or more electrical variables;
• a signal processing unit, the signal processing unit estimating q real quantities depending on the impedance matrix presented by the user ports, where q is an integer greater than or equal to m, by utilizing the sensing unit output signals obtained for m excitations applied to the user ports, one and only one of the excitations being applied to each of the user ports, each of the excitations having one and only one complex envelope, the m complex envelopes of the m excitations being linearly independent in the set of complex functions of one real variable, regarded as a vector space over the field of complex numbers, the signal processing unit delivering a tuning instruction as a function of the q real quantities depending on the impedance matrix presented by the user ports;
• and
• a tuning control unit, the tuning control unit receiving the tuning instruction from the signal processing unit, the tuning control unit delivering tuning control signals to the tunable passive antennas, the tuning control signals being determined as a function of the tuning instruction, each of said parameters being mainly determined by one or more of the tuning control signals.