Isotropic noise in an antenna study .pptx

Noise Information and Study

1. ISOTROPIC NOISE DIRECTING STAFF COL M NAVALAN PRESENTED BY MAJ AKSHAT DOGRA LO 2.1.4

2. INTRODUCTION Random noise radiation which reaches a location from all directions with equal intensity. LO 2.1.4

3. AIM TO STUDY THE VARIOUS CAUSES AND EFFECTS OF ISOTROPIC NOISE ON RADAR ANTENNA LO 2.1.4

4. ARRAY GAIN The array gain is often used as an indicator of overall array performance . LO 2.1.4

5. ARRAY RESPONSE NEAR FIELD AND FAR FIELD RESPONSE LO 2.1.4

6. IMPORTANCE OF SNR LO 2.1.4

7. 3D HOLOGRAPHIC RADAR Biggest hurdle was negotiating the surrounding noise due to low SNR LO 2.1.4

8. NOISE FIGURE MEASURE OF DEGRADATION OF SNR CAUSED BY THE COMPONENTS IN RF CHAIN FOR A GIVEN BW. F n  =  available output noise power available output noise due to source LO 2.1.4

9. ANTENNA TEMP EQUIVALENT TEMP ASSOCIATED WITH RECEIVED POWER Pa AT THE ANTENNA TERMINALS. LO 2.1.4

10. NOISE TEMP For an antenna with a  radiation pattern  given by  the noise temperature is mathematically defined as: LO 2.1.4

11. GAIN TO NOISE TEMP Antenna gain-to-noise-temperature  (G/T) is a  figure of merit  in the characterization of  antenna  performance. LO 2.1.4

12. CAUSES OF ISOTROPIC NOISE ANTENNA DESIGN OP TEMP LENGTH OF TXN LINE NO OF JOINTS DISTANCE OF TX FROM THE ANTENNA TYPES OF CABLE USED MODES OF EXCITATION OF RADIATING ELEMENTS LO 2.1.4

13. RADAR SYSTEM EVOLUTION LO 2.1.4

14. KEY DIFFERENCES LO 2.1.4

15. NOISE FIGURE LO 2.1.4

16. MUTUAL COUPLING AFFECTS ANTENNA ARRAY PARAMETERS LIKE TERMINAL IMPEDENCE, RCS, SNR. COUPLING EFFECTS THE STEADY STATE AND TRANSIENT RESPONSE AND INTERFERENCE REJECTION CAPABILITIES. LO 2.1.4

17. NOISE REDUCTION LOW PASS FILTER KALMAN FILTERING DIGITAL DOPPLER FILTERING CFAR CORRELATORS LO 2.1.4

18. EFFECT OF NOISE EFFECT AT NOISE LEVEL OF 0%, 10%, 50% AND 100% LO 2.1.4

19. NOISE REDUCTION CAPABILITIES LO 2.1.4

20. NOISE REDUCTION CAPABILITIES LO 2.1.4

21. FUTURE TRENDS CRYOGENIC SOLID STATE DEVICES LO 2.1.4

22. IMP INFERENCES NOISE IS PREDOMINANT VARIOUS CAUSES FOR NOISE CAN BE REDUCED BUT NOT ELIMINATED COMPLETELY REDUCTION TECHNIQUES LIKE KALMAN FILTERING CAN IMPROVE ANTENNA AND RADAR PERFORMANCE GIVING BETTER RECIEVER SENSITIVITY, SELECTIVITY AND SNR. LO 2.1.4

23. IMP QUESTIONS What are the various causes of isotropic noise? Define array gain, noise figure and antenna temperature. Explain the different noise reduction techniques used in radar. LO 2.1.4