Radio frequency system with switch to receive envelope

Abstract

Aspects of this disclosure relate to a radio frequency system that includes an envelope generator configured to generate an envelope signal corresponding to an envelope of a radio frequency signal and at least two radio frequency components coupled to the envelope generator. One of the radio frequency components is a radio frequency switch configured to pass the radio frequency signal. The radio frequency switch is configured to receive the envelope signal to cause intermodulation distortion associated with the radio frequency switch to be reduced.

1 . (canceled) 
     
     
         2 . A radio frequency system comprising:
 an envelope generator configured to generate an envelope signal corresponding to an envelope of a radio frequency signal; and   a radio frequency switch configured to pass the radio frequency signal, the radio frequency switch including a field effect transistor having a body configured to receive the envelope signal to cause intermodulation distortion associated with the radio frequency switch to be reduced.   
     
     
         3 . The radio frequency system of  claim 2  wherein the field effect transistor has a gate configured to receive the envelope signal superimposed on a control signal, and the radio frequency switch is configured to turn on and to turn off responsive to the control signal. 
     
     
         4 . The radio frequency system of  claim 2  wherein the envelope generator is configured to adjust a phase of the envelope signal such that intermodulation associated with mixing of the envelope signal and the radio frequency signal has substantially an opposite phase as the intermodulation distortion associated with the radio frequency switch. 
     
     
         5 . The radio frequency system of  claim 4  wherein the envelope generator is configured to adjust a magnitude of the envelope signal such that the intermodulation distortion associated with the radio frequency switch has substantially the same magnitude as the intermodulation associated with mixing of the envelope signal and the radio frequency signal. 
     
     
         6 . The radio frequency system of  claim 2  wherein the radio frequency signal includes a first tone at a first frequency and a second tone at a second frequency, and the envelope signal has a third frequency corresponding to a difference between the first frequency and the second frequency. 
     
     
         7 . The radio frequency system of  claim 2  further comprising a power amplifier configured to provide the radio frequency signal to the radio frequency switch. 
     
     
         8 . The radio frequency system of  claim 7  further comprising an envelope tracking modulator coupled to the envelope tracker, the envelope tracking modulator configured to provide a power amplifier supply voltage to the power amplifier. 
     
     
         9 . A radio frequency system comprising:
 an envelope generator configured to generate an envelope signal corresponding to an envelope of a radio frequency signal; and   a radio frequency switch configured to pass the radio frequency signal, the radio frequency switch including a transistor configured to receive the radio frequency signal, the transistor having a control terminal configured to receive the envelope signal superimposed on a control signal, and the transistor being configured to turn on and to turn off responsive to the control signal.   
     
     
         10 . The radio frequency system of  claim 9  wherein the transistor is a field effect transistor, and the control terminal is a gate of the field effect transistor. 
     
     
         11 . The radio frequency system of  claim 9  wherein the envelope generator is configured to adjust a phase of the envelope signal such that intermodulation associated with mixing of the envelope signal and the radio frequency signal has substantially an opposite phase as the intermodulation distortion associated with the radio frequency switch. 
     
     
         12 . The radio frequency system of  claim 11  wherein the envelope generator is configured to adjust a magnitude of the envelope signal such that the intermodulation distortion associated with the radio frequency switch has substantially the same magnitude as the intermodulation associated with mixing of the envelope signal and the radio frequency signal. 
     
     
         13 . The radio frequency system of  claim 9  wherein the radio frequency signal includes a first tone at a first frequency and a second tone at a second frequency, and the envelope signal has a third frequency corresponding to a difference between the first frequency and the second frequency. 
     
     
         14 . The radio frequency system of  claim 9  further comprising a power amplifier configured to provide the radio frequency signal and an envelope tracking modulator coupled to the envelope tracker, the envelope tracking modulator configured to provide a power amplifier supply voltage to the power amplifier. 
     
     
         15 . The radio frequency system of  claim 9  wherein the envelope generator and the radio frequency switch are embodied on a single semiconductor die. 
     
     
         16 . The radio frequency system of  claim 9  wherein the envelope generator is configured to receive the radio frequency signal from an output of the switch and to generate the envelope signal based on the radio frequency signal. 
     
     
         17 . A wireless communication device comprising:
 an antenna;   a power amplifier configured to provide a radio frequency signal;   an envelope generator configured to generate an envelope signal associated with the radio frequency signal, the envelope generator being configured to adjust a phase and a magnitude of the envelope signal; and   a radio frequency switch in a signal path between the power amplifier and the antenna, the radio frequency switch being configured to receive the envelope signal.   
     
     
         18 . A wireless communication device of  claim 17  wherein the switch includes a field effect transistor having a body configured to receive the envelope signal. 
     
     
         19 . A wireless communication device of  claim 17  wherein the switch includes a field effect transistor having a gate configured to receive the envelope signal superimposed with a control signal, the field effect transistor being configured to turn on and to turn off responsive to the control signal. 
     
     
         20 . A wireless communication device of  claim 17  wherein the wireless communication device is a mobile phone. 
     
     
         21 . A wireless communication device of  claim 17  further comprising a processor configured to process baseband signals, a transceiver coupled between the processor and a radio frequency front end, the radio frequency switch being included in the radio frequency front end.