In an infrared missile, where is the modulation done in order to track the target?

In an infrared missile, tracking the target relies on detecting the infrared radiation emitted by it. The modulation is crucial for distinguishing the target from the background as it helps encode information about the target’s attributes. This modulation happens at the signal processing level after being collected by the optics and detected by the sensor.

The signal processor is responsible for processing the raw data received from the detector, applying algorithms and modulation techniques to track the target effectively. By comparing the modulated signals, the system can focus on specific targets based on their thermal signatures.

In contrast, the optics serve primarily to gather and focus the incoming infrared radiation but do not perform modulation. The reticle is used in targeting systems but does not play a role in the modulation process. The detector captures the infrared signals but relies on the signal processor to interpret and modulate these signals accurately for target tracking.

Thus, the signal processor is the correct choice, as it is where the critical modulation needed for effective target tracking is performed.