METHOD OF TRANSMISSION AND DEVICE TO CARRY OUT METHOD THEREOF

摘要

PURPOSE: A method is provided which a plurality of SAW filter is disposed on an ultrasonic substrate as a dispersion filter and from which, plus and minus stage of ultrasonic sphere can be produced and developed. CONSTITUTION: A method of transmission whereby angularly modulated pulses are produced in a transmitter and angle modulation occurs in reverse chronological order during pulse duration. In each case pulses are superimposed in pairs by means of a first superimposition element (8,9) to form a folded pulse. The folded pulses transmitted to the receiver carry information which was impressed upon them by the modulation process and are filtered in the receiver by two complementary parallel connected dispersion filters with a frequency-dependent group transit time characteristic. Said characteristic of both dispersion filters is adapted in each case to the angle modification of one of the two pulses forming the folded pulse by superimposition, so that in each case a combined signal appears at the dispersion filter output consisting of a compressed pulse with increased amplitude and one with reduced amplitude. The signals are brought together at the outputs of both receive side dispersion filters by means of a second superimposition element.