Which devices can serve as a local oscillator in a RADAR receiver?

A local oscillator in a RADAR receiver is crucial for processing received signals. It provides a stable frequency reference that is mixed with the incoming RADAR signal to create an intermediate frequency (IF), which is then easier to filter and amplify.

Klystrons are vacuum tube devices that can effectively generate microwave frequencies, making them suitable for use as local oscillators in RADAR systems. They are known for their ability to produce high power and frequency stability, which is essential in RADAR applications.

Gunn diodes, on the other hand, are solid-state devices that can also generate microwave signals and are commonly used as local oscillators due to their compact size and efficiency. They work on the principle of negative resistance, allowing them to oscillate at microwave frequencies. Their ability to generate stable microwave signals makes them an ideal candidate for RADAR systems as well.

Since both Klystron and Gunn diode can function as local oscillators in RADAR receivers, the correct answer encompasses their combined capabilities. This highlights the versatility and range of technologies available for local oscillation in sophisticated RADAR systems.