Lots of transmitters even budget ones have an ABS Function built in, check if yours does.
If your model uses servos for brakes I think they might be too slow to implement a useful ABS function, a better approach would be to use your transmitter 'end point adjustments' to reduce the braking power so that you cannot lock up.
If your convinced that your servos are fast enough then that there are a few projects I have published which provide active control of RC Cars, this being one example - http://rcarduino.blogspot.ae/2012/07/rcarduino-yaw-control-part-2.html
or this with the addition of a few lines of code to reduce the braking power as each light is activatedhttp://rcarduino.blogspot.ae/2013/06/rc-arduino-traction-control-traction.html
These are better approaches because they activley sense what is happening to the car before deciding how much to intervene in the signal.