Question about a drive way sensor

[heehaw]

that "was" my thought too; except it also misses my wifes toyota corolla, an ya can't get much lower than that; i have the sensor @6-8 ft from the driveway; fairly low to the ground, and aimed up, to try to avoid the local critters; i've moved it around a lot, and am still movin, thats why i am thinking about mounting it directly over the drive and aimed at the ground; something would have to go directly under the sensor to trigger the transmitter; as it is now, the middle of the driveway and the sensor appear to meet at @ 30-36 inches high;
heehaw