Experimental Demonstration of Photonic Subtraction and Addition of Microwave Signals

Among various techniques of photonic microwave signal generation, the approach of two cascaded electro-optic modulators performing subtraction and adding frequencies of injected signals is demonstrated. The novelty of this work lies in the fact that the generated signal sidebands are useful, unlike others, where they should be eliminated. These signals are advantageously used for microwave system applications. A multi-frequency signal with high spectral purity is obtained and specific frequencies can be selected depending on the needs.