Answer / anj050588

radar antenna illuminates the target with a microwave
signal, which is then reflected and picked up by a
receiving device. The electrical signal picked up by the
receiving antenna is called echo or return. The radar
signal is generated by a powerful transmitter and received
by a highly sensitive receiver.
depending upon the time taken by the signal to return to
the radar receiver, target distance can be estimated. also
change in characteristics like frequency deviation of the
echoe signal velocity can be estimated using dopplers effect

Answer / madhu

the above answer is absolutely correct and i want to add a new point:the direction of the target is also calculated depending on the frequency of the echo signal.if the echo frequency is the sum of the transmitted frequency and the beat frequency,it is considered as the target being traced is approaching our radar and if its the difference considered as target is moving away from our radar.

Why 440 volts instead of 660 volts in 3 phases of supply system?

0 Answers  

---

Why do we use FM for sound and AM for video in TV transmisssion?

5 Answers   DRDO,

---

Why diodes should be connected in antiparallel with thethyristors in inverter circuits?

0 Answers  

---

What is faithfull amplification?

1 Answers   Syntel, Wipro,

---

Why we use 50Hz sine wave for AC?

7 Answers  

---

Define peak inverse voltage?

0 Answers  

---

why to study at university of new haven ?

0 Answers   Visa,

---

What are the advantages of ac voltage controllers?

0 Answers  

---

what is the difference between multiplexing and multiple accessing?

3 Answers   Polmon,

---

what is a GPIB?

2 Answers   BEL,

---

What is optical fiber?

6 Answers   CTS,

---

Explain why an ammeter should be of very low resistance?

0 Answers  

---