Recursive Discrete Time Oscillator with Dynamic Amplitude Control

G.K. Vikram (10115044)Arka Ghosh (10115024)

Debasmit Das (10115039)

TWO ENTITIES

• Recursive Oscillator – It is a numerical oscillator which can be described by a recurrence relation.

• Dynamic amplitude control - The control technique used is Automatic Gain Control. It is used to encounter accidental instability.

Recursive Oscillator

BLOCK DIAGRAM

STATE EQUATION

|zI – A | = 0 and |z|=1 Yields the condition of a sustained oscillations -

ad – bc =1 and | a+d | < 2

So these parameters determine whether the oscillator is stable .

a=0.5 ,b=-3,c=0.25,d=0.5

a=0.5 , b=3, c=0.5 , d=0.6??

Calls for Automatic Gain Control

• Gain is tuned according to the amplitude of the signal

• If signal is weak then gain should be large and if signal is strong gain should be weak.

• Applications : Radio Sets , Amplifiers

• No Approximation of Gain required

REFERENCES

• Clay S. Turner , A Discrete Time Oscillator for a DSP based Radio

• Clay S. Turner, DSP Tips & Tricks, IEEE Signal Processing Magazine

• www.google.co.in

THANK YOU

SPECIAL THANKS TO DR. P. SUMATHI