The enemy can prevent you from warping in two ways by blocking the warp engine of your ship by modules such as Warp Scrambler I or Warp Disruptor I warp jammers, and by changing the vector of acceleration of your ship to the gate by simply ramming your ship if you are rich of Aion Gold. Speed and maneuverability will help against the second threat.
And against the warp jammers, there am opposite devices Warp Core Stabilizer I. You should put warp stabilizers into all the lower slots to prevent the warp engine from being blocked.
Math here is simple almost every engine has power 1; the above mentioned modules have exactly the same power. For example, if you have 3 stabilizers, the total force will be four. If the enemy uses against you 3 jammers 3 strength, the jump is still possible.