Communications device with separate i and q phase power amplification having selective phase and magnitude adjustment and related methods

A communications device comprising:

• an In-phase (I) circuit comprising an In-phase modulator and mixer circuit, and an I power amplifier circuit coupled thereto, said I circuit configured to modulate and amplify a digital baseband I signal to generate an amplified I signal;
• a Quadrature (Q) circuit comprising a Q modulator and mixer circuit, and a Q power amplifier circuit coupled thereto, said Q circuit configured to modulate and amplify a digital baseband Q signal to generate an amplified Q signal separate from the amplified I signal;
• a power combiner configured to sum the separately amplified I and Q signals and output a combined I and Q signal;
• an I demodulator circuit configured to demodulate a feedback signal from said I power amplifier circuit and to produce a demodulated I signal;
• a Q demodulator circuit configured to demodulate a feedback signal from said Q power amplifier circuit and to produce a demodulated Q signal;
• a processor configured to compare the digital baseband I and Q signals with the demodulated I and Q signals to compensate for errors;
• I and Q signal inputs coupled to said I and Q circuits respectively and being isolated from the combined I and Q signal;
• and
• an antenna coupled to said power combiner;
• said processor configured to selectively switch the digital baseband I signal and the digital baseband Q signal between the I and Q signal inputs to provide selective phase shifting for at least one of the digital baseband I and Q signals and to predistort the digital baseband I and Q signals fed to said I and Q circuits to compensate for the amplitude, frequency and phase modulation errors.

A mobile wireless communications device, comprising:

• a housing;
• an antenna carried by the housing;
• and
• at least one circuit board carried by the housing and including radio frequency (RF) circuitry carried by said at least one circuit board and comprising a transceiver connected to said antenna through which RF communications signals are transmitted and received, and a processor carried by said at least one circuit board and operative with said RF circuitry, wherein said transceiver further comprises an In-phase and Quadrature (I/Q) modulation and power amplification circuit comprising
• an In-phase (I) circuit comprising an In-phase modulator and mixer circuit, and an I power amplifier circuit coupled thereto, said I circuit configured to modulate and amplify a digital baseband I signal to generate an amplified I signal,
• a Quadrature (Q) circuit comprising a Q modulator and mixer circuit, and a Q power amplifier circuit coupled thereto, said Q circuit configured to modulate and amplify a digital baseband Q signal to generate an amplified Q signal separate from the amplified I signal,
• a power combiner configured to sum the separately amplified I and Q signals and output a combined I and Q signal,
• an I demodulator circuit configured to demodulate a feedback signal from said I power amplifier circuit and to produce a demodulated I signal,
• a Q demodulator circuit configured to demodulate a feedback signal from said Q power amplifier circuit and to produce a demodulated Q signal,
• a processor configured to compare the digital baseband I and Q signals with the demodulated I and Q signals to compensate for errors, and
• I and Q signal inputs coupled to said I and Q circuits respectively and being isolated from the combined I and Q signal,
• said processor configured to selectively switch the digital baseband I signal and the digital baseband Q signal between the I and Q signal inputs to provide selective phase shifting for at least one of the digital baseband I and Q signals.

A method of operating a communications device comprising:

• providing an In-phase (I) circuit comprising an In-phase modulator and mixer circuit, and an I power amplifier circuit coupled thereto for modulating and amplifying a digital baseband I signal to generate an amplified I signal;
• providing a Quadrature (Q) circuit comprising a Q modulator and mixer circuit, and a Q power amplifier circuit coupled thereto for modulating and amplifying a digital baseband Q signal to generate an amplified Q signal separate from the amplified I signal;
• using a power combiner to sum the separately amplified I and Q signals and to output a combined I and Q signal;
• using an I demodulator circuit to demodulate a feedback signal from the I power amplifier circuit and to produce a demodulated I signal;
• using a Q demodulator circuit to demodulate a feedback signal from the Q power amplifier circuit and to produce a demodulated Q signal;
• using a processor to compare the digital baseband and Q signals with the demodulated I and Q signals to compensate for errors;
• isolating I and Q signal inputs coupled to the I and Q circuits respectively from the combined I and Q signal;
• and
• using the processor to selectively switch the digital baseband I signal and the digital baseband Q signal between the I and Q signal inputs to provide selective phase shifting for at least one of the digital baseband I and Q signals.

A communications device comprising:

• an In-phase (I) circuit comprising an In-phase modulator and mixer circuit, and an I power amplifier circuit coupled thereto, said I circuit configured to modulate and amplify a digital baseband I signal to generate an amplified I signal;
• a Quadrature (Q) circuit comprising a Q modulator and mixer circuit, and a Q power amplifier circuit coupled thereto, said Q circuit configured to modulate and amplify a digital baseband Q signal to generate an amplified Q signal separate from the amplified T signal;
• a power combiner configured to sum the separately amplified I and Q signals and output a combined I and Q signal;
• an I demodulator circuit configured to demodulate a feedback signal from said I power amplifier circuit and to produce a demodulated I signal;
• a Q demodulator circuit configured to demodulate a feedback signal from said Q power amplifier circuit and to produce a demodulated Q signal;
• I and Q signal inputs coupled to said I and Q circuits respectively and being isolated from the combined and Q signal;
• and
• a processor configured to
• compare the digital baseband I and Q signals with the demodulated I and Q signals to compensate for errors,
• selectively phase shift at least one of the digital baseband I and Q signals, and
• control at least one of said I and Q power amplifier circuits to vary an amplitude of at least one of the amplified I and Q signals.

A communications device comprising:

• an In-phase (I) circuit comprising an In-phase modulator and mixer circuit, and an I power amplifier circuit coupled thereto, said I circuit configured to modulate and amplify a digital baseband I signal to generate an amplified I signal;
• a Quadrature (Q) circuit comprising a Q modulator and mixer circuit, and a Q power amplifier circuit coupled thereto, said Q circuit configured to modulate and amplify a digital baseband Q signal to generate an amplified Q signal separate from the amplified I signal;
• a power combiner configured to sum the separately amplified I and Q signals and output a combined I and Q signal;
• an I demodulator circuit configured to demodulate a feedback signal from said I power amplifier circuit and to produce a demodulated I signal;
• a Q demodulator circuit configured to demodulate a feedback signal from said Q power amplifier circuit and to produce a demodulated Q signal;
• I and Q signal inputs coupled to said I and Q circuits respectively and being isolated from the combined I and Q signal;
• an antenna coupled to said power combiner;
• and
• a processor configured to
• compare the digital baseband I and Q signals with the demodulated I and Q signals to compensate for errors,
• selectively phase shift at least one of the digital baseband I and Q signals,
• control at least one of said I and Q power amplifier circuits to vary an amplitude of at least one of the amplified I and Q signals, and
• predistort the digital baseband I and Q signals fed to said I and Q circuits to compensate for the amplitude, frequency and phase modulation errors.

A mobile wireless communications device, comprising:

• a housing;
• an antenna carried by the housing;
• and
• at least one circuit board carried by the housing and including radio frequency (RF) circuitry carried by said at least one circuit board and comprising a transceiver connected to said antenna through which RF communications signals are transmitted and received, and a processor carried by said at least one circuit board and operative with said RF circuitry, wherein said transceiver further comprises an In-phase and Quadrature (I/Q) modulation and power amplification circuit comprising
• an In-phase (I) circuit comprising an In-phase modulator and mixer circuit, and an I power amplifier circuit coupled thereto, said I circuit configured to modulate and amplify a digital baseband I signal to generate an amplified I signal,
• a Quadrature (Q) circuit comprising a Q modulator and mixer circuit, and a Q power amplifier circuit coupled thereto, said Q circuit configured to modulate and amplify a digital baseband Q signal to generate an amplified Q signal separate from the amplified I signal,
• a power combiner configured to sum the separately amplified I and Q signals and output a combined I and Q signal,
• an I demodulator circuit configured to demodulate a feedback signal from said I power amplifier circuit and to produce a demodulated I signal,
• a Q demodulator circuit configured to demodulate a feedback signal from said Q power amplifier circuit and to produce a demodulated Q signal,
• I and Q signal inputs coupled to said I and Q circuits respectively and being isolated from the combined I and Q signal, and
• a processor configured to
• compare the digital baseband I and Q signals with the demodulated I and Q signals to compensate for errors,
• selectively phase shift at least one of the digital baseband I and Q signals, and
• control at least one of said I and Q power amplifier circuits to vary an amplitude of at least one of the amplified I and Q signals.

A method of operating a communications device comprising:

• providing an In-phase (I) circuit comprising an In-phase modulator and mixer circuit, and an I power amplifier circuit coupled thereto, the I circuit modulating and amplifying a digital baseband I signal to generate an amplified I signal;
• providing a Quadrature (Q) circuit comprising a Q modulator and mixer circuit, and a Q power amplifier circuit coupled thereto, the Q circuit modulating and amplifying a digital baseband Q signal to generate an amplified Q signal separate from the amplified I signal;
• using a power combiner to sum the separately amplified I and Q signals and output a combined I and Q signal;
• using an I demodulator circuit to demodulate a feedback signal from the I power amplifier circuit and to produce a demodulated I signal;
• using a Q demodulator circuit to demodulate a feedback signal from the Q power amplifier circuit and to produce a demodulated Q signal;
• isolating I and Q signal inputs coupled to the I and Q circuits respectively from the combined I and Q signal;
• comparing the digital baseband I and Q signals with the demodulated I and Q signals to compensate for errors;
• selectively phase shifting at least one of the digital baseband I and Q signals;
• and
• controlling at least one of the I and Q power amplifier circuits to vary an amplitude of at least one of the amplified I and Q signals.