Rbe is the input resistance of BJT transistor, which is defined as the slope of BJT input characteristic curve, that is, the ratio of input emitter junction voltage increment to base current increment. Rbe consists of three parts: 1. Base volume resistance rbb is generally tens to 2300 ohms; 2. The emitter volume resistance is very small and generally neglected; 3. The formula of base and emitter junction resistance related to β and current IE is β×26(mv)/I(ma) (Boltzmann constant).

The English abbreviation "RBE" is often used as the abbreviation of "random belief equilibrium", and Chinese means "random belief equilibrium".