Could LI DAR pick-up an incorrect speed if used through traffic passing in front of them?

I was given a citation for speeding in my personal vehicle, for 15 miles over the speed limit. I have a CDL and the highway patrol officer used this device through tightly packed traffic in front of him, and supposedly caught me coming under a bridge towards him. I was going 8 miles over the speed limit, but how do I approach the judge about my company will fire me if I have a speeding ticket for going 10 miles over the limit? The officer stated, and wrote on the ticket, that i was going 15 miles over the limit, and that he believed that 15 over the speed limit will be an enhancement, I do not even know what that is. Any advice as to asking for leniency, or lowering the actual miles over? Please help.. I don't know what to do, or even how I would fight this. I will be homeless if I lose my job. I live in California if that helps?