Die Optimalschaetzung als vorteilhafte Alternative zur Korrelation in Radarsystemen mit expandierten Impulsen

In pulse radar systems, expanded waveforms with large time bandwidth products are used in order to get high impulse energy and large impulse bandwidth and, consequently, high accuracy if transmitters with limited peak power have to be used. In such cases, the received signal is usually processed by correlation, i.e. matched filtering. By doing so, the unavoidable correlation sidelobes of expanded waveforms are very harmful to accuracy. Because of this, in practice only a small class of expanded waveforms which are especially designed for low correlation sidelobes can be used. In this paper, optimum unbiased maximum likelihood estimation is proposed as a favourable alternative to correlation methods. Theoretical calculations and simulation results show that, when using the presented estimation algorithms the problems caused by correlation sidelobes do no longer exist. Similar to matched filters the optimum unbiased estimators have the favourable property of interference suppression.