Class-AB radio frequency amplifier for envelope detector

摘要

An envelope detector (ED) includes a voltage-mode ED core including parallel detection transistors for detecting a voltage envelope of a radio frequency (RF) signal input, the RF signal input including an output of a radio such as a cellular transmitter (TX). The ED further includes multiple voltage amplifiers positioned serially in gain stages between the TX output and the ED core to provide a total linear voltage range of the envelope detector. A final voltage amplifier of the multiple voltage amplifiers drives the ED core and includes a class-AB RF amplifier configured to operate within a full linear voltage range of the ED core.

主权项

1. An envelope detector comprising:
a voltage-mode envelope detector (ED) core including parallel detection transistors configured to detect a voltage envelope of a radio frequency (RF) signal input, the RF signal input including a cellular transmitter (TX) output; and multiple voltage amplifiers positioned serially in gain stages between the TX output and the ED core and configured to provide a first linear voltage range of the envelope detector, where the multiple voltage amplifiers comprise a driving voltage amplifier configured to drive the ED core and that comprises a class-AB RF amplifier configured to operate over a second linear voltage range of the ED core.