A system including a power amplifier having a first gain, a preamplifier having a second gain, a first temperature sensor configured to sense the temperature of the power amplifier, and a bias generator. The first gain is a function of a temperature of the power amplifier. The preamplifier receives an input signal, amplifies the input signal according to the second gain, and outputs an amplified signal to the power amplifier. The bias generator generates a biasing signal to bias the preamplifier and adjusts the second gain of the preamplifier by adjusting the biasing signal based on the temperature of the power amplifier and an ambient temperature. The adjusted second gain of the preamplifier compensates a change in the first gain of the power amplifier due to a change in the temperature of the power amplifier.