Hi,
I am trying to design an AM active mixer in double balanced gilbert cell configuration. I have the proper signals (power+ DC bias) given to both RF inputs and LO inputs but I seem to get a negative conversion gain.
What could be the possible flaws that I would be making in it
thanks for the reply
i believe I am giving the inputs(power level with right phases+dc level) for both RF inputs(left with RF+ and right with RF-) (the bottom differential pair) and LO+ inputs [(top leftmost & top rightmost) &(the rest two middle transistors with LO- inputs)
I could see the IF i needed in the output which is 455kHz for a suitable RF and LO frequency. But the power level of IF is almost 100 times(linear scale) lower than RF level. I dont know where the issue is, as I never designed a mixer before.