Maximum radar range is directly related to which factor?

Maximum radar range is directly related to which factor?

• A. the transmitted power
• B. Transmitter pulse duration
• C. Receiver bandwidth
• D. Antenna apex angle

Answer: (A)

The main idea is the link budget: how far you can detect a target depends on how much power you put into the pulse and how that power translates into a detectable return. In the radar range equation, the received power falls off with the fourth power of range, while it increases linearly with transmitted power. When you set the received power equal to the minimum detectable signal, the maximum detectable range ends up growing with the transmitted power to the one-fourth power. In practical terms, doubling the transmitted power increases the maximum range, but only by a factor of about 1.19 (since 2^(1/4) ≈ 1.19). This makes transmitted power the most direct lever for extending maximum range. Pulse duration affects the energy per pulse and can help with detection under certain conditions, and receiver bandwidth affects the noise floor and thus sensitivity, but neither changes the fundamental way range scales with transmit power as directly as increasing the transmit power does. Antenna beamwidth (apex angle) influences gain and thus the received signal, but the core, most straightforward factor tied to maximum range is how much power is sent out.

The main idea is the link budget: how far you can detect a target depends on how much power you put into the pulse and how that power translates into a detectable return. In the radar range equation, the received power falls off with the fourth power of range, while it increases linearly with transmitted power. When you set the received power equal to the minimum detectable signal, the maximum detectable range ends up growing with the transmitted power to the one-fourth power. In practical terms, doubling the transmitted power increases the maximum range, but only by a factor of about 1.19 (since 2^(1/4) ≈ 1.19). This makes transmitted power the most direct lever for extending maximum range.

Pulse duration affects the energy per pulse and can help with detection under certain conditions, and receiver bandwidth affects the noise floor and thus sensitivity, but neither changes the fundamental way range scales with transmit power as directly as increasing the transmit power does. Antenna beamwidth (apex angle) influences gain and thus the received signal, but the core, most straightforward factor tied to maximum range is how much power is sent out.