GUIDANCE SYSTEMS

     Guidance determines appropriate missile flight path dynamics to achieve the mission objectives and miss distance. It finds the latest position of missile during the flight and provides the required error corrections. DRDO has developed the following guidance systems under the IGMDP.

STRAP-DOWN INERTIAL GUIDANCE SYSTEMS
       Strap-down inertial guidance systems based on DTG and force balanced accelerometers for short and medium range tactical missiles has been developed. DRDO has also developed navigation algorithm with embedded software and global positioning system (GPS)-inertial navigation system, transfer alignment schemes, GPS-aided navigation, and sensor modelling for various types of missiles.


Strap-down Inertial Guidance System

Optical gyroscopes such as ring laser gyroscope (RLG) of inertial class and fiber optic gyroscope (FOG) of both control and inertial class has been developed to reduce the reaction time and for high navigational accuracy.

Gyros
Fiber Optic Gyroscope
FOG is an optical gyroscope working on the basic principle of Saganac interferometer. It is having numerous advantages over the conventional mechanical gyroscopes because of the absence of any moving mechanical parts. Small size, lightweight, no acceleration dependent g drift, faster reaction time, and low maintenance are some of the other important features of FOG.
The integrating technology of the FOG is highly flexible, which helps in achieving various grades of performances just by varying the coil dimensions and length. Inertial grade FOGs are developed concurrent with the indigenous development of integrated optical chip.
Ring Laser Gyro
A RLG of inertial class has been developed using total internal reflection prisms. The complete optical processing, inspection, design of electronics for RLG control and measurement have been realised. RLG can be used in any missile with longer flight time and in LCA.

RF COMMAND GUIDANCE SYSTEMS
    
DRDO has developed RF command guidance systems including transponder, command link system, twin antenna switching and hybrid MIC and various types of antennas systems such as cassegrain reflector monopulse antenna, monopulse corrugated horn and lightweight trans-twist monopulse antenna.

Seekers
Seekers are used to accurately guide missiles to their targets. DRDO has developed seekers like visible CCD seeker, IIR seeker, and MMW seeker along with image processing system for scene matching.

Imaging Infrared Seekers
Imaging infrared seekers are widely used either for implementing the homing guidance principle in short-range tactical missions or for achieving the required terminal accuracy for the long-range air defence scenario.


MMW Seeker                  IIR Seeker

Salient Features

  •  Long-wave infrared operation

  •  Thermalised imaging optics

  •  2-D FPA-based sensor

  •  Double axis gyro stabilised platform

  •  Multimode target tracking algorithm

  •  Real-time DSP-based image processor

  •  Efficient onboard software

  •  Compact hermetically sealed configuration

THREE-CHANNEL MONOPULSE RECEIVER
         A three-channel monopulse receiver has been developed in the Ku-band using state-of-the-art hybrid MIC technology. The receiver has been designed, modelled and simulated for performance against various input and environmental conditions before its practical realisation. The size of the receiver is 55 m x 45 m x 20 mm.

The component will be used as the front-end receiver in the indigenously designed and developed seeker. The size and mounting have been so chosen that it can be mounted on the back of antenna. The three-channel monopulse receiver will replace the costlier imported receiver front-ends.