Technology for reducing packet transmissions is disclosed. The device comprises an applicator including a source of microwave radiation and an array of retractable needles arranged so as to extend from one face of the applicator and, in operation, to confine the irradiated microwave energy field emanating from the applicator. , predictive encoding, DCT processing, quantization at fixed quantization step size and variable length encoding to generate first encoded data to determine allocated code quantity every frame or every GOP on the basis of data quantity every predetermined time, e. These recognized strings are then compared against vehicle registration information stored in a database in order to identify each vehicle travelling under along the roadway.