Frequency synthesis is a technique used to generate a range of frequencies from a single reference frequency. This process is essential in various applications, such as telecommunications and signal processing, where precise frequency generation is required. By combining different frequencies through methods like phase-locked loops (PLLs) or direct digital synthesis (DDS), engineers can create stable and accurate signals. The generated frequencies can be used in devices like radios, cell phones, and GPS systems. Frequency synthesis allows for the creation of complex waveforms and enables the tuning of devices to specific frequencies, improving performance and functionality in modern technology.