Dual band cellular phone with two power amplifiers and a current detector for monitoring the consumed power

Claim 2

A cellular phone for a mobile communications system, said cellular phone being operable at a first radio frequency band and a second radio frequency band comprising a dual band transmitter, a power supply and an antenna, said dual band transmitter comprising: a first power amplifier couoled to said power supply, said first power amplifier having a first input for a first signal at said first radio frequency band, a second input for a first control signal, a final amplification stage and a first output for an amplified first signal, said first output being connectable to said antenna; a first detector, said first detector being associated with said power supply and the final amplification stage of said first power amplifier and generating a first detection signal indicative of power drawn by the final amplification stage of said first power amplifier from said power supply when said first power amplifier is active; a second power amplifier coupled to said power supply, said second power amplifier having a third input for a second signal at said second radio frequency band, a fourth input for a second control signal, a final amplification stage and a second output for an amplified second signal, said second output being connectable to said antenna; a second detector, said second detector being associated with said power supply and the final amplification stage of said second power amplifier and generating a second detection signal indicative of power drawn by the final amplification stage of said second power amplifier from said power supply when said second power amplifier is active; and a control module, said control module being associated with said first and second detectors and generating a control signal to control one of said power amplifiers, said control signal being a function of one of said first and second detection signals and a reference signal.

Claim 3

The cellular phone of claim 1, wherein said first radio frequency band is about 900 MHz, and said second radio frequency band is about 1800 MHz.

Claim 4

The cellular phone of claim 1, wherein said first radio frequency band is about 900 MHz, and said second radio frequency band is about 1900 MHz.

Claim 5

The cellular phone of claim 1, wherein said control module comprises: a differential amplifier, said differential amplifier having a third input for receiving a reference signal and having a fourth input for one of said first and second detection signals, and generating an error signal corresponding to a difference between said reference signal and said detection signal; an integrator, said integrator integrating said error signal and generating an integrated error signal; and a shaping circuit, said circuit weighing said integrated error signal in accordance with characteristics of said first and second power amplifiers to generate said control signal which equalizes nonlinear amplification characteristics of said power amplifiers.

Claim 6

The cellular phone of claim 4, wherein said control module further comprises a switch, said switch being controllable and feeding said control signal to one of said power amplifiers.

Claim 7

The cellular phone of claim 5, wherein said control module further comprises a first amplifier and a second amplifier, said first amplifier being connected to a first terminal of said switch and driving said first power amplifier, and said second amplifier being connected to a second terminal of said switch and driving said second power amplifier.

Claim 8

The cellular phone of claim 1, wherein said first and second detectors comprise a detector responsive to the input current of the first and second power amplifier.

Claim 9

A transmitter for a cellular phone comprising an antenna and being operable at a first radio frequency band and a second radio frequency band, said transmitter comprising: a first power amplifier coupled to a power supply, said first power amplifier having a first input for a first signal at said first radio frequency band, a second input for a first control signal, a final amplification stage and a first output for an amplified first: signal, said first output being connectable to said antenna; a first detector, said first detector being associated with said power supply and the final amplification stage of said first power amplifier and generating a first detection signal indicative of power drawn by the final amplification stage of said first power amplifier from said power supply when said first power amplifier is active; a second power amplifier coupled to said power supply, said second power amplifier having a third input for a second signal at said second radio frequency band, a fourth input for a second control signal, a final amplification stage and a second output for an amplified second signal, said second output being connectable to said antenna; a second detector, said second detector being associated with said power supply and the final amplification stage of said second power amplifier and generating a second detection signal indicative of power drawn by the final amplification stage of said second power amplifier from said power supply when said second power amplifier is active; and a control module, said control module being associated with said first and second detectors and generating a control signal to control one of said power amplifiers, said control signal being a function of one of said first and second detector signals and a reference signal.

Claim 10

A transmitter for a cellular phone comprising an antenna and being operable at a first radio frequency band and a second radio frequency band, said transmitter comprising: a first power amplifier coupled to a power supply, said first power amplifier having a first input for a first signal at said first radio frequency band, a second input for a first control signal, a final amplification stage and a first output for an amplified first: signal, said first output being connectable to said antenna; a first detector, said first detector being associated with said power supply and the final amplification stage of said first power amplifier and generating a first detection signal indicative of power drawn by the final amplification stage of said first power amplifier from said power supply when said first power amplifier is active; a second power amplifier coupled to said power supply, said second power amplifier having a third input for a second signal at said second radio frequency band, a fourth input for a second control signal, a final amplification stage and a second output for an amplified second signal, said second output being connectable to said antenna; a second detector, said second detector being associated with said power supply and the final amplification stage of said second power amplifier and generating a second detection signal indicative of power drawn by the final amplification stage of said second power amplifier from said power supply when said second power amplifier is active; and a control module, said control module being associated with said first and second detectors and generating a control signal to control one of said power amplifiers, said control signal being a function of one of said first and second detector signals and a reference signal.

Claim 11

The transmitter of claim 8, wherein said control module comprises: a differential amplifier, said differential amplifier having a third input for receiving a reference signal and having a fourth input for one of said detection signal, and generating an error signal corresponding to a difference between said reference signal and said detection signal; an integrator, said integrator integrating said error signal and generating an integrated error signal; and a shaping circuit, said circuit weighing said integrated error signal in accordance with characteristics of said first and second power amplifiers to generate said control signal which equalizes nonlinear amplification characteristics of said power amplifiers.

Claim 12

The transmitter of claim 9, wherein said control module further comprises a switch, said switch being controllable and feeding said control signal to one of said power amplifiers.

Claim 13

The transmitter of claim 8, wherein said control module further comprises a first amplifier and a second amplifier, said first amplifier being connected to a first terminal of said switch and driving said first power amplifier, and said second amplifier being connected to a second terminal of said switch and driving said second power amplifier.

Claim 14

The transmitter of claim 8, wherein said detector comprises a current sensor which monitors the current of at least one stage of said first and second power amplifier.

Claim 15

The transmitter of claim 12, wherein said detector comprises first and second detector associated with said first and second power amplifier.

Claim 18

A cellular phone for a mobile communications system, said cellular phone being, operable at a first radio frequency band and a second radio frequency band comprising a dual band transmitter, a power supply and an antenna, said dual band transmitter comprising: a first power amplifier, said first power amplifier having a first input for a first signal at said first radio frequency band, a second input for a first control signal, a final amplification stage and a first output for an amplified first signal, said first output being connectable to said antenna; a first detector, said first detector being associated with the final amplification stage of said first power amplifier and generating a first detection signal indicative of power consumed by the final amplification stage of said first power amplifier when said first power amplifier is active; a second power amplifier, said second power amplifier having a third input for a second signal at said second radio frequency band, a fourth input for a second control signal, a final amplification stage and a second output for an amplified second signal, said second output being connectable to said antenna; a second detector, said second detector being associated with the final amplification stage of said second power amplifier and generating a second detection signal indicative of power consumed by the final amplification stage of said second power amplifier when said second power amplifier is active; and a control module, said control module being associated with said first and second detectors and generating a control signal to control one of said power amplifiers, said control signal being a function of one of said first and second detection signals and a reference signal, the control module comprising: a differential amplifier, said differential amplifier having a third input for receiving a reference signal and having a fourth input for one of said first and second detection signals, and generating an error signal corresponding to a difference between said reference signal and said detection signal; an integrator, said integrator integrating said error signal and generating an integrated error signal; and a shaping circuit, said circuit weighing said integrated error signal in accordance with characteristics of said first and second power amplifiers to generate said control signal which equalizes nonlinear amplification characteristics of said power amplifiers.

Claim 19

A cellular phone for a mobile communications system, said cellular phone being, operable at a first radio frequency band and a second radio frequency band comprising a dual band transmitter, a power supply and an antenna, said dual band transmitter comprising: a first power amplifier, said first power amplifier having a first input for a first signal at said first radio frequency band, a second input for a first control signal, a final amplification stage and a first output for an amplified first signal, said first output being connectable to said antenna; a first detector, said first detector being associated with the final amplification stage of said first power amplifier and generating a first detection signal indicative of power consumed by the final amplification stage of said first power amplifier when said first power amplifier is active; a second power amplifier, said second power amplifier having a third input for a second signal at said second radio frequency band, a fourth input for a second control signal, a final amplification stage and a second output for an amplified second signal, said second output being connectable to said antenna; a second detector, said second detector being associated with the final amplification stage of said second power amplifier and generating a second detection signal indicative of power consumed by the final amplification stage of said second power amplifier when said second power amplifier is active; and a control module, said control module being associated with said first and second detectors and generating a control signal to control one of said power amplifiers, said control signal being a function of one of said first and second detection signals and a reference signal, the control module comprising: a differential amplifier, said differential amplifier having a third input for receiving a reference signal and having a fourth input for one of said first and second detection signals, and generating an error signal corresponding to a difference between said reference signal and said detection signal; an integrator, said integrator integrating said error signal and generating an integrated error signal; and a shaping circuit, said circuit weighing said integrated error signal in accordance with characteristics of said first and second power amplifiers to generate said control signal which equalizes nonlinear amplification characteristics of said power amplifiers.

Claim 20

The cellular phone of claim 15, wherein said control module further comprises a switch, said switch being controllable and feeding said control signal to one of said power amplifiers.

Claim 21

The cellular phone of claim 16, wherein said control module further comprises a first amplifier and a second amplifier, said first amplifier being connected to a first terminal of said switch and driving said first power amplifier, and said second amplifier being connected to a second terminal of said switch and driving said second power amplifier.

Claim 22

A transmitter for a cellular p comprising an antenna and being operable at a first radio frequency band and a second radio frequency band, said transmitter comprising: a first power amplifier, said first power amplifier having a first input for a first signal at said first radio frequency band, a second input for a first control signal, a final amplification stage and a first output for an amplified first signal, said first output being connectable to said antenna; a first detector, said first detector being associated with the final amplification stage of said first power amplifier and generating a first detection signal indicative of power consumed by the final amplification stage of said first power amplifier when said first power amplifier is active; a second power amplifier, said second power amplifier having a third input for a second signal at said second radio frequency band, a fourth input for a second control signal, a final amplification stage and a second output for an amplified second signal, said second output being connectable to said antenna; a second detector, said second detector being associated with the final amplification stage of said second power amplifier and generating a second detection signal indicative of power consumed by the final amplification stage of said second power amplifier when said second power amplifier is active; and a control module, said control module being associated with said first and second detectors and generating a control signal to control one of said power amplifiers, said control signal being a function of one of said first and second detector signals and a reference signal, wherein said control module comprises: a differential amplifier, said differential amplifier having a third input for receiving a reference signal and having a fourth input for one of said detection signal, and generating an error signal corresponding to a difference between said reference signal and said detection signal; an integrator, said integrator integrating said error signal and generating an integrated error signal; and a shaping circuit, said circuit weighing said integrated error signal in accordance with characteristics of said first and second power amplifiers to generate said control signal which equalizes nonlinear amplification characteristics of said power amplifiers.

Claim 23

A transmitter for a cellular p comprising an antenna and being operable at a first radio frequency band and a second radio frequency band, said transmitter comprising: a first power amplifier, said first power amplifier having a first input for a first signal at said first radio frequency band, a second input for a first control signal, a final amplification stage and a first output for an amplified first signal, said first output being connectable to said antenna; a first detector, said first detector being associated with the final amplification stage of said first power amplifier and generating a first detection signal indicative of power consumed by the final amplification stage of said first power amplifier when said first power amplifier is active; a second power amplifier, said second power amplifier having a third input for a second signal at said second radio frequency band, a fourth input for a second control signal, a final amplification stage and a second output for an amplified second signal, said second output being connectable to said antenna; a second detector, said second detector being associated with the final amplification stage of said second power amplifier and generating a second detection signal indicative of power consumed by the final amplification stage of said second power amplifier when said second power amplifier is active; and a control module, said control module being associated with said first and second detectors and generating a control signal to control one of said power amplifiers, said control signal being a function of one of said first and second detector signals and a reference signal, wherein said control module comprises: a differential amplifier, said differential amplifier having a third input for receiving a reference signal and having a fourth input for one of said detection signal, and generating an error signal corresponding to a difference between said reference signal and said detection signal; an integrator, said integrator integrating said error signal and generating an integrated error signal; and a shaping circuit, said circuit weighing said integrated error signal in accordance with characteristics of said first and second power amplifiers to generate said control signal which equalizes nonlinear amplification characteristics of said power amplifiers.

Claim 24

The transmitter of claim 18, wherein said control module further comprises a switch, said switch being controllable and feeding said control signal to one of said power amplifiers.