Method and system for adjusting the amplitude and phase characteristics of real and imaginary signal components of complex signals processed by an analog radio transmitter

A digital baseband (DBB) transmitter comprising:

• a digital phase imbalance compensation module having real and imaginary signal paths and being configured to adjust the phase difference between the real and imaginary signal paths;
• and
• a controller in communication with the digital phase imbalance compensation module and being configured to determine a phase compensation value used to adjust the phase difference between the real and imaginary signal paths to 90 degrees;
• a digital amplitude imbalance compensation module in communication with the controller and having real and imaginary signal paths in communication with the real and imaginary signal paths of the digital phase imbalance compensation module, respectively, wherein the controller determines an amplitude compensation value used by the digital amplitude imbalance compensation module to adjust the amplitude characteristics of the imaginary signal path such that the real and imaginary signal paths substantially have the same amplitude;
• a modem switchably connected to the real and imaginary signal paths of the digital amplitude imbalance compensation module, the modem having real and imaginary signal outputs;
• and
• first and second switches connected to the real and imaginary signal outputs of the modem, the real and imaginary signal paths of the digital amplitude imbalance compensation module and the controller, wherein the amplitude and phase compensation values are determined after the switches disconnect the modem from the real and imaginary signal paths of the digital amplitude imbalance compensation module and connect the controller to the real and imaginary signal paths of the digital amplitude imbalance compensation module.

A wireless transmit/receive unit (WTRU) comprising:

• a digital amplitude imbalance compensation module having real and imaginary signal paths, the digital amplitude imbalance compensation module being configured to adjust the amplitude characteristics of the real and imaginary signal paths;
• a controller in communication with the digital amplitude imbalance compensation module, the controller being configured to determine an amplitude compensation value used to adjust the amplitude characteristics of the imaginary signal path such that the real and imaginary signal paths substantially have the same amplitude;
• a digital phase imbalance compensation module in communication with the controller and having real and imaginary signal paths in communication with the real and imaginary signal paths of the digital amplitude imbalance compensation module, respectively, wherein the controller determines a phase compensation value used by the digital phase imbalance compensation module to adjust the phase difference between the real and imaginary signal paths to 90 degrees;
• a modem switchably connected to the real and imaginary signal paths of the digital amplitude imbalance compensation module, the modem having real and imaginary signal outputs;
• and
• first and second switches connected to the real and imaginary signal outputs of the modem, the real and imaginary signal paths of the digital amplitude imbalance compensation module and the controller, wherein the amplitude and phase compensation values are determined after the switches disconnect the modem from the real and imaginary signal paths of the digital amplitude imbalance compensation module and connect the controller to the real and imaginary signa1 paths of the digital amplitude imbalance compensation module.

A wireless transmit/receive unit (WTRU) comprising:

• a digital phase imbalance compensation module having real and imaginary signal paths and being configured to adjust the phase difference between the real and imaginary signal paths;
• and
• a controller in communication with the digital phase imbalance compensation module and being configured to determine a phase compensation value used to adjust the phase difference between the real and imaginary signal paths to 90 degrees;
• a digital amplitude imbalance compensation module in communication with the controller and having real and imaginary signal paths in communication with the real and imaginary signal paths of the digital phase imbalance compensation module, respectively, wherein the controller determines an amplitude compensation value used by the digital amplitude imbalance compensation module to adjust the amplitude characteristics of the imaginary signal path such that the real and imaginary signal paths substantially have the same amplitude;
• a modem switchably connected to the real and imaginary signal paths of the digital amplitude imbalance compensation module, the modem having real and imaginary signal outputs;
• and
• first and second switches connected to the real and imaginary signal outputs of the modem, the real and imaginary signal paths of the digital amplitude imbalance compensation module and the controller, wherein the amplitude and phase compensation values are determined after the switches disconnect the modem from the real and imaginary signal paths of the digital amplitude imbalance compensation module and connect the controller to the real and imaginary signal paths of the digital amplitude imbalance compensation module.

An integrated circuit (IC) comprising:

• a digital amplitude imbalance compensation module having real and imaginary signal paths, the digital amplitude imbalance compensation module being configured to adjust the amplitude characteristics of the real and imaginary signal paths;
• a controller in communication with the digital amplitude imbalance compensation module, the controller being configured to determine an amplitude compensation value used to adjust the amplitude characteristics of the imaginary signal path such that the real and imaginary signal paths substantially have the same amplitude;
• a digital phase imbalance compensation module in communication with the controller and having real and imaginary signal paths in communication with the real and imaginary signal paths of the digital amplitude imbalance compensation module, respectively, wherein the controller determines a chase compensation value used by the digital phase imbalance compensation module to adjust the phase difference between the real and imaginary signal paths to 90 degrees;
• a modem switchably connected to the real and imaginary signal paths of the digital amplitude imbalance compensation module, the modem having real and imaginary signal outputs;
• and
• first and second switches connected to the real and imaginary signal outputs of the modem, the real and imaginary signal paths of the digital amplitude imbalance compensation module and the controller, wherein the amplitude and phase compensation values are determined after the switches disconnect the modem from the real and imaginary signal paths of the digital amplitude imbalance compensation module and connect the controller to the real and imaginary signal paths paths of the digital amplitude imbalance compensation module.

An integrated circuit (IC) comprising:

• a digital phase imbalance compensation module having real and imaginary signal paths and being configured to adjust the phase difference between the real and imaginary signal paths;
• and
• a controller in communication with the digital phase imbalance compensation module and being configured to determine a phase compensation value used to adjust the phase difference between the real and imaginary signal paths to 90 degrees;
• a digital amplitude imbalance compensation module in communication with the controller and having real and imaginary signal paths in communication with the real and imaginary signal paths paths of the digital phase imbalance compensation module, respectively, wherein the controller determines an amplitude compensation value used by the digital amplitude imbalance compensation module to adjust the amplitude characteristics of the imaginary signal path such that the real and imaginary signal paths substantially have the same amplitude;
• a modem switchably connected to the real and imaginary signal paths paths of the digital amplitude imbalance compensation module, the modem having real and imaginary signal outputs;
• and
• first and second switches connected to the real and imaginary signal outputs of the modem, the real and imaginary signal paths paths of the digital amplitude imbalance compensation module and the controller, wherein the amplitude and phase compensation values are determined after the switches disconnect the modem from the real and imaginary signal paths paths of the digital amplitude imbalance compensation module and connect the controller to the real and imaginary signa1 paths of the digital amplitude imbalance compensation module.