A new Doherty amplifier design approach

The conventional Doherty amplifier requires the auxiliary device current to increase faster than the main as the input power increases. This has been accomplished by additional control circuitry, or uneven power drive, or periphery scaling. This paper presents a new Doherty design approach that accepts the insufficient auxiliary device current. It is shown that with this approach, comparable power back-off efficiency is achieved while linearity is maintained.