Regrettably - we all end up at the short end of a speeding ticket. I am not a lawyer, and I am a litigation support specialist - ever wonder how the big name lawyers seem to know their stuff
There are different tactics you can utilize - most of them on your own devices.
1) Get on the internet and determine what "local" jurisdiction you were caught (where you need to appear in court)
2) Send a letter to the prosecutor (with proof of mailing and service) to request the calibration information of the radar/laser unit, submit written questions (interrogatories) requesting info on service history of officer, number of tickets written, number dismissed, etc.
3) Request number and model of laser/radar units in service, age, repair history, etc.
The point is, as long as you have requested this information (discovery) the other side has to supply. If they do not respond to you, ignore you, etc. The judge will be forced to dismiss. Most likely the prosecutor will not want to put the effort in to getting all the information you have requested and drop the case.
At the very least you can continue to get continuances until the one time the officer can not make it and the judge will dismiss. Remember, you may be summoned to appear (in which the officer will be present for several tickets) and you send a letter requesting a different date - and the one time the officer does not make it - dismissed.
These tactics are used all the time - trust me, this is how I make my living!
Make it a Good One!