Class-AB radio frequency amplifier for envelope detector
AssigneeBroadcom Corporation
InventorsAmir Hadji-Abdolhamid, Janice Chiu
Life of this patent
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Abstract
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.
Claims20
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.
An envelope detector comprising:
- a voltage-mode envelope detector (ED) core configured to detect a voltage envelope of a radio frequency (RF) signal;
- an RF input configured to receive the RF signal from a transmitter;
- the ED core characterized by a first linear voltage range;
- and
- series connected amplifiers comprising:
- a first amplifier stage configured to receive the RF signal;
- and
- a second amplifier stage in series after the first amplifier stage, the second amplifier stage comprising a class-AB RF amplifier and configured to drive the ED core in operation over the first linear voltage range;
- the series connected amplifiers configured to provide, with the envelope detector core, a second linear voltage range that is greater in extent than the first linear voltage range.
A method comprising:
- receiving, with an envelope detector (ED), a radio frequency (RF) input from a signal transmitter driver, the ED configured to detect a voltage envelope of the RF input;
- passing the RF input to a first amplifier stage of series connected amplifiers of the ED, where the ED is characterized by a first linear voltage range;
- passing an output of the first amplifier stage through the series connected amplifiers to a driving amplifier stage comprising a class-AB RF amplifier;
- and
- driving a voltage-mode envelope detector (ED) core of the ED with the class-AB RF amplifier over a second linear voltage range of the ED core that is smaller in extent than the first linear voltage range.
Dependencies are inferred from the claim text.