Patent ID: 9515613
Filing Date: 2016-12-06
CPC Classification: H03F

Claim Text:
1. A Doherty amplifier comprising: a first Doherty amplifier gain element; a first transmission line coupled to a first output of the first Doherty amplifier gain element, wherein the first transmission line comprises, for a first frequency band, a first series of a first number of quarter-wave transmission line elements; a second Doherty amplifier gain element; a second transmission line coupled to a second output of the second amplifier gain element, wherein the second transmission line comprises, for the first frequency band, a second series of a second number of quarter-wave transmission line elements, wherein the first number is not equal to the second number, wherein the first series provides, for a second frequency band, a third number of quarter-wave transmission line elements and the second series provides, for the second frequency band, a fourth number of quarter-wave transmission line elements, a first difference between the first number and the third number and a second difference between the second number and the fourth number based on a difference of wavelengths between the first band and the second band; and a gate bias circuit for providing a first bias signal to the first Doherty amplifier gain element and a second bias signal to the second Doherty amplifier gain element when a signal being amplified by the Doherty amplifier is in the first frequency band and for providing the first bias signal to the second Doherty amplifier gain element and the second bias signal to the first Doherty amplifier gain element when the signal is in the second frequency band.