An LTE transmitter using a class-A/B power mixer

For an LTE transceiver it is quite challenging to reduce power and area while preserving performance. For large emitted signals the TX dominates power consumption but in the past this situation was sufficiently infrequent not to affect energy consumption. In recent times the statistical distribution of the TX power has shifted upward due to the use of data-intensive communications and the introduction of multi-gain power amplifiers. Therefore to extend battery life in fourth generation terminals, TX consumption at high power (>-10dBm) should be reduced. A second challenge of an FDD LTE TX is noise and distortion emission in the RX band since the TX-to-RX distance, relative to the channel bandwidth, can be much smaller than in previous standards [1].