This project presents the concept and design of a reconfigurable microwave discriminator with two ports. This circuit is the core element in a reconfigurable frequency measurement system. The microwave discriminator is the component that must perform the function of detecting unknown frequencies within the 30-40 GHz range (Ka band), targeted operational frequency of the receiver. The microwave discriminator behaving a 180° phase shifter implemented with a hybrid coupler, power splitter which also as a power combiner and a λ / 2 reference line of a length, all these elements are designed with coplanar (CPW) transmission lines on a glass substrate. The phase shifter is designed using an hybrid coupler and switched transmission lines, which will allow obtaining a phase difference of 180° between each state. The power divider/combiner is also designed with coplanar transmission lines using the well-known Wilkinson two-stage branch topology. The divider/combiner is connected to the reference line and the 180° phase shifter. The two signals are then combined at the output, producing two bits for frequency identification. It is noteworthy that the proposed device is designed to be implemented with micromachining and MicroElectroMechanical Systems (MEMS) technology to achieve a compact size, with negligible power consumption by using electrostatic operation to produce the two discrete states of the device.