R u getting noise in simulation itself or on circuit. If it is on cicuit use proper power supply bypass and higain amplifier. If it is in simulation do as sggested in first reply.
Hope this helps
The noise contribution of PMOS and NMOS current sources increases in proportion to their transconductance. This trend results in a trade-off between output voltage swings and input-referred noise:for a given current, as implied by gm=2Id/(Vgs-Vth), if the overgrive voltage of the current sources is minimized to allow large swings, then their transconductance is maximized.