The present disclosure relates generally to cellular and wireless devices and, more particularly, to cellular and wireless devices having transmitters capable of regulating the operating characteristics of a power amplifier corresponding to operating modes of the transmitter.
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
Transmitters are commonly included in various electronic devices, and particularly, portable electronic devices such as, for example, phones (e.g., mobile and cellular phones, cordless phones, personal assistance devices), computers (e.g., laptops, tablet computers), internet connectivity routers (e.g., Wi-Fi routers or modems), radios, televisions, or any of various other stationary or handheld devices. Certain types of transmitters, known as wireless transmitters, may be used to generate wireless signals to be transmitted by way of an antenna coupled to a power amplifier in the transmitter. The power amplifier of the transmitter may apply a suitable gain to a signal to increase the signal's strength for better transmission over a channel (e.g., air). Further, the power amplifier may function at an optimum level of efficiency based on a power output of the power amplifier and a supply voltage used to power the power amplifier. As such, for a given power input to the power amplifier, there may exist a supply voltage that may result in the optimum level of efficiency and/or gain characteristics for the power amplifier. Thus, envelope tracking (ET) techniques may be used to track the amplitudes and shape of an input power signal so that the envelope of the supply voltage signal may be shaped to supply a suitable voltage level to the power amplifier at each amplitude of the input power signal's envelope. However, as transceivers become more complex and provide different modes of operation, it may be difficult to maintain optimum performance of the power amplifier.