Method and apparatus for multiple-output partial envelope tracking in handheld wireless computing devices

A wireless computing device, comprising:

• a radio frequency transmitter including a multi-input-multi-output (MIMO) module including a plurality of power amplifiers connected to a plurality of antennas, wherein the radio frequency transmitter is configured to transmit radio frequency (RF) signals;
• a partial envelope tracking (PET) circuity for improving the dynamic range of the plurality of power amplifiers amplifying RF signals, including:
• a plurality of sub-PET circuits respectively connected to the plurality of power amplifiers;
• and
• a common charging circuit connected to each of the plurality of sub-PET circuits and a power source, wherein the common charging circuit comprises a storage capacitor and a logic configured to control the charging of the storage capacitor respective of an operation mode of each of the plurality of sub-PET circuits, wherein the operation mode is any one of:
• a tracking mode and a normal mode, wherein during the normal mode of all of the plurality of sub-PET circuits the storage capacitor is charged at the voltage level provided by the power source and during the tracking mode of at least one of the plurality of sub-PET circuits the storage capacitor is discharged.

The wireless computing device 18, wherein the VEC consists of:

• a main supply path having a main valve (MV) connecting the power amplifier to the power source;
• a supplementary supply path including a diversion valve (DV) and a tracking valve (TV);
• and
• a valves control unit (VCU) configured to monitor a respective binary envelope tracking parameter to determine a state of each of the main valve, the diversion valve, and tracking valve during of an operation mode of the VEC.

A method for improving the dynamic range of a plurality of power amplifiers amplifying radio frequency (RF) signals in a multi-input-multi-output (MIMO) based wireless computing device, comprising:

• providing a plurality of sub-PET circuits respectively connected to the plurality of power amplifiers;
• and
• providing a common charging circuit connected to each of the plurality of sub-PET circuits and a power source, wherein the common charging circuit comprises a single storage capacitor and a logic;
• monitoring a plurality of binary envelope tracking parameters to determine an operation mode of the common charging circuit, wherein the operation mode is any one of:
• a tracking mode and a normal mode;
• and
• controlling the charging of the single storage capacitor respective of the determined operation mode, wherein during the normal mode the storage capacitor is charged at the voltage level provided by the power source and during the tracking mode the storage capacitor is discharged.