Method and apparatus for calibrating multiple antennas

An apparatus for calibrating multiple antennas in a radio communication device, the radio communication device being configured with a transmission, TX, circuit and a receiving, RX, circuit for each of the multiple antennas, each pair of the TX circuit and the RX circuit coupled to the corresponding antenna in normal antenna operation, the apparatus comprising:

• a first TX oscillator coupled to one or more of the TX circuits to supply the one or more TX circuits with a TX working frequency in the normal antenna operation;
• and
• a first RX oscillator coupled to one or more of the RX circuits to supply the one or more RX circuits with a RX working frequency in the normal antenna operation,
• a second TX oscillator coupled to the one or more TX circuits to supply the one or more TX circuits with a RX calibrating frequency in an antenna RX calibration operation;
• and
• a second RX oscillator coupled to the one or more RX circuits to supply the one or more RX circuits with a TX calibrating frequency in an antenna TX calibration operation,
• wherein the TX working frequency is the same as the TX calibrating frequency, and the RX working frequency is the same as the RX calibrating frequency.

An apparatus for calibrating multiple antennas in a radio communication device, the radio communication device being configured with a transmission, TX, circuit and a receiving, RX, circuit for each of the multiple antennas, each pair of the TX circuit and the RX circuit coupled to the corresponding antenna in normal antenna operation, the apparatus comprising:

• a first oscillator coupled to one or more of the TX circuits to supply the one or more TX circuits with a TX working frequency, and coupled to one or more of the RX circuits to supply the one or more RX circuits with a TX calibrating frequency, wherein the TX working frequency and TX calibrating frequency are supplied in an antenna TX calibration operation;
• and
• a second oscillator coupled to the one or more RX circuits to supply the one or more RX circuits with a RX working frequency, and coupled to the one or more TX circuits to supply the one or more TX circuits with a RX calibrating frequency, wherein the RX working frequency and RX calibrating frequency are supplied in an antenna RX calibration operation,
• wherein the TX working frequency is the same as the TX calibrating frequency, and the RX working frequency is the same as the RX calibrating frequency.

A method for calibrating multiple antennas in a radio communication device, the radio communication device being configured with a transmission, TX, circuit and a receiving, RX, circuit for each of the multiple antennas, each pair of the TX circuit and the RX circuit coupled to the corresponding antenna in normal antenna operation, the method comprising:

• establishing a calibrating circuit for the multiple antennas, wherein the calibrating circuit comprises a first TX oscillator and a first RX oscillator, wherein the first TX oscillator is coupled to one or more of the TX circuits to supply the one or more TX circuits with a TX working frequency and a RX calibrating frequency, and the first RX oscillator is coupled to one or more of the RX circuits to supply the one or more RX circuits with a RX working frequency and a TX calibrating frequency;
• in an antenna TX calibration operation, controlling the first TX oscillator to supply the one or more TX circuits with the TX working frequency, and the first RX oscillator to supply the one or more RX circuits with the TX calibrating frequency, wherein the TX working frequency is the same as TX calibrating frequency;
• and
• in an antenna RX calibration operation, controlling the first TX oscillator to supply the one or more TX circuits with the RX calibrating frequency, and the first RX oscillator to supply the one or more RX circuits with the RX working frequency, wherein the RX working frequency is the same as RX calibrating frequency.

A method for calibrating multiple antennas in a radio communication device, the radio communication device being configured with a transmission, TX, circuit and a receiving, RX, circuit for each of the multiple antennas, each pair of the TX circuit and the RX circuit coupled to the corresponding antenna in normal antenna operation, the method comprising:

• establishing a calibrating circuit for the multiple antennas, wherein the calibrating circuit comprises a first TX oscillator and a first RX oscillator, wherein the first TX oscillator is coupled to one or more of the TX circuits to supply the one or more TX circuits with a TX working frequency in the normal antenna operation, and the first RX oscillator is coupled to one or more of the RX circuits to supply the one or more RX circuits with a RX working frequency in the normal antenna operation;
• wherein the calibrating circuit further comprises a second TX oscillator and a second RX oscillator, wherein the second TX oscillator is coupled to the one or more TX circuits to supply the one or more TX circuits with a RX calibrating frequency, and the second Rx oscillator is coupled to the one or more RX circuits to supply the one or more RX circuits with a TX calibrating frequency;
• in an antenna TX calibration operation, controlling the second RX oscillator to supply the one or more RX circuits with the TX calibrating frequency, wherein the TX working frequency is the same as TX calibrating frequency;
• and
• in an antenna RX calibration operation, controlling the second TX oscillator to supply the one or more TX circuits with the RX calibrating frequency, wherein the RX working frequency is the same as RX calibrating frequency.

A method for calibrating multiple antennas in a radio communication device, the radio communication device being configured with a transmission, TX, circuit and a receiving, RX, circuit for each of the multiple antennas, each pair of the TX circuit and the RX circuit coupled to the corresponding antenna in normal antenna operation, the method comprising:

• establishing a calibrating circuit for the multiple antennas, wherein the calibrating circuit comprises a first oscillator and a second oscillator, wherein the first oscillator is coupled to one or more of the TX circuits to supply the one or more TX circuits with a TX working frequency, and is coupled to one or more of the RX circuits to supply the one or more RX circuits with a TX calibrating frequency, the second oscillator coupled to the one or more RX circuits to supply the one or more RX circuits with a RX working frequency, and coupled to one or more TX circuits to supply the one or more TX circuits with a RX calibrating frequency;
• in an antenna TX calibration operation, controlling the first oscillator to supply the one or more TX circuits with the TX working frequency, and to supply the one or more RX circuits with the TX calibrating frequency, wherein the TX working frequency is the same as the TX calibrating frequency;
• and
• in an antenna RX calibration operation, controlling the second oscillator to supply the one or more TX circuits with the RX calibrating frequency, and to supply the one or more RX circuits with the RX working frequency, wherein the RX working frequency is the same as RX calibrating frequency.