We report linear, enhanced transconductance by high-medium-low doped-channel FET. A low-doped layer together with n+ and p+ layers establishes high-performance camel diode, which exhibits a high effective potential barrier of ≫ 1.0 V and a gate-drain breakdwon voltage of around 21 V (at I g = 1.0 mA/mm). Whereas the transition and the thin, high-doped layers used to enhance transconductance and to improve device linearity. A 1.5×100 ?m2 camel-diode gate FET (CAMFET) has a peak transconductance of 220 mS/mm and a current density of ≫ 800 mA/mm. On the other hand, the device has a transconductance of more than 80 percent of the peak value over a wide drain current range of 160 to 800 mA/mm. The improvement of device linearity and the enhancement of current density suggest that high-medium-low doped channel for a CAMFET is suitable for high power large signal circuit applications.