Mixing

FREQUENCY MIXERS Eduard Bertran 1 MIXERS 2 IDEAL MIXERS MIXERS 3 MIXERS 4 UPCONVERTER Ideally, these signals CAN NOT be seen altogether 𝑤𝑤𝑜𝑜=𝑤𝑤𝐿𝐿𝐿𝐿 MIXERS 5 UPCONVERTER MIXERS 6 DOWNCONVERTER 0 ( )cos( )ft t ω ( ) 2 00 0 1 ( )cos ( ) ( ) 1 cos(2 ) 2 11 () ()cos(2 ) 22 ft t ft t ft ft t ωω ω = + = + 0 cos( )t ω Low pass filter ()ft {} 2 0 00 11 1 ()cos( ) () ( 2) ( 2) 24 4 F ft t F F F ω ω ωω ωω = +−++ ω A/4 2ω0 A/4 -2ω0 A/2 MIXERS 7 DOWNCONVERTER 𝑓𝑓 𝑅𝑅𝑅𝑅= 𝑓𝑓 0 HOMODYNE (single frequency, ONE STEP) MIXERS 8 MIXERS ARE SIMULTANEOUSLY UP and DOWN CONVERTERS MIXERS 9 DOWNCONVERTER INTERMEDIATE FREQUENCY 16