How to increase the conversion gain of a single balanced CMOS mixer?

I am trying to design a Single Balanced CMOS mixer. How can I increase the conversion gain of the mixer? In RF Microelectronics by Razavi he says to increase the width of the switching transistors but that decreases my conversion gain. While increasing the width I decreased the biasing to keep the tail current constant but it still didn't work.
Please suggest how to get my gain up or any resources where I can find some design tips.
Also if I run a transient analysis, what should be the waveforms I should expect to see. My LO is 1.7GHz and RF is 1.8GHz. I use a tail transistor which convertes the RF signal to current and feeds it to the tail current of the Single Balanced mixer. If I check the waveform at the RF input node I am getting mixing at that node ! I get a modulated signal with a frequency of nearly 1.7GHz and a modulation frequency which is close to IF of 100MHz.

try in decrease the width of the load transistors ,
it will increase the gain

or u can increase the width of the transconductor tarnsistor , ecause it is the responsible for the gain

khouly

Dear,

What is your input power of your LO signal? If it is not large enough, the communtating stage is not model as a switch. It is like to multiple two sinusoidal waves. The IF power will smaller. I hope this is useful to you.

Best Regards,
wccheng

My LO signal is 2 volt peak to peak. Also I have Resistor loads not transistors. I tried changing their values but there is one optimum value for which the gain is maximum and I found that to be 400 ohms

Dear aryajur,

Are you simulated the power conversion gain? Do you do matching?

Best Regards,

wccheng

I am doing the voltage conversion gain and yes I also have matching at the input.

How is your bias?
you try to bias the commutating stage in Vth.
and the RF input transistor in saturation region.

then, give a enough power of the LO in order to opreate the commutating stage as switch.

you see see the gain is better or not.

wccheng