Schottky diode-based doublers are the crucial elements for room temperature high spectral resolution terahertz heterodyne receiver in planetary science and remote sensing. Here, a discrete Schottky diode-based terahertz doubler which acts as the LO for the receiver working up to 400 GHz range was presented. Measured performance is essentially in agreement with predictions from linear/nonlinear co-simulations and this methodology is practicability for the discrete planar GaAs Schottky diodes-based frequency doubler design. (c) 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:966-970, 2017