The design guide section of ADS for Mixer design

Hi everyone,

I used "design guides" of ADS for mixer simulation. In this section, the conversion gain of the example mixer has a negative value! As you know the typical value of conversion gain for a mixer is about 10dB (RF Microelectronics, Razavi).

Is it possible to have a negative value for conversion gain of active mixer.

Thanks,
Rosa

It's possible... it means you used a wrong load..

the default conversion gain in "mixer design guide" is power conversion gain, and it do has negative value!

you can name the i/o pin, and get the voltage conversion gain such as:

ConvGain_voltage=dbm(mix(HB.Voutp,{1,-1}))-dbm(mix(HB.Vinp,{0,1}))

if f_LO > f_RF

it can happen , if u didn't adjust the load ,and the gm of the transconductor pair , also check the matching so u get the max output

khouly

Passive mixer definitely introduce negative conversion gain (or in other word, conversion loss).