Designing a circuit that only mixes is not all that difficult. You already have an oscillator which oscillates at a desired frequency. You give this to the Emitter of a BJT and Your input signal should go to its base. The output is obtained at the collector, after filtering the desired harmonic out.
yeah.......I have gone through all those books...what my problem is.....while designing any circuit,generally we try to relate the specs and from those we calculate the required bias voltages and widths of the transistors.......how to ralate the same in the mixer as noise figure and 1 dB compression point and others we can not directly formulate.............and how to start the designing process.........
Hii,
In my mixer circuit in the LO ,I have used a pulse source and its peak amplitude is 250mV and source resistance is 100 ohm...so how to claculate the LO power in dBm?and what is maximum LO amplitude that can be used in mixers?
hi!
the LO stage is used as a commutation stage from bloced to saturated not from bloced to linear region.
So the best region is near the threashold region whith out being in linear region.
Added after 5 minutes:
hi!
the LO power is calculated as follows:
Plo= V²lo/R
to convert it in dbm:
Plodbm=10log(Plo/10^(-3)).
Hii,
In my mixer circuit in the LO ,I have used a pulse source and its peak amplitude is 250mV and source resistance is 100 ohm...so how to claculate the LO power in dBm?and what is maximum LO amplitude that can be used in mixers?
Hii,
The mixer I designed has 1dB compression point .36dBm.RF frequency is 2.4GHz.
For calculating IIP3 I have used second tone as 2.401G in addition to 2.4GHz RF signal.Is it right?
While plotting IIP3 in cadence what should I take as the extrapolation point,because when I change that point the value of IIP3 will change.....Help me.....