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If a carrier wave c ( t )= A _ c t is amplitude modulated by a modulator signal m ( t )= A sin _ m t then the equation of modulated signal [ C _ m ( t ) ] and its modulation index are respectively

Options

  1. AC_m(t)=A (1+ _m t ) _c t and 2
  2. BC_m(t)=A (1+ _m t ) _m t and 1
  3. CC_m(t)=A (1+ _m t ) _c t and 1
  4. DC_m(t)=A (1+ _c t ) _m t and 2

Correct answer

C. C_m(t)=A (1+ _m t ) _c t and 1

Step-by-step solution

Modulation index m _ a = E _ m E _ c = A A =1 Equation of modulated signal [ C _ m ( t ) ] = E _ ( C ) + m _ a E _ ( C ) _ m ^ t = A (1+ w _ C t ) _ m t ( . As . E _ ( C ) = A _ c t )

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