Improving Costas Radar Signal by Applying Variable Time Spacing Using Costas Array And Golomb Ruler

The normal Costas frequencies code sequence signal is very well known and important signal in pulse compression Radar. In this paper we present two algorithms to modify Costas sequence by arranging the frequencies of Costas signal in time, first using binary Costas array and second using Golomb Ruler. These methods enable us to control side-lobes and to improve Doppler frequency resolution of Ambiguity Function (AF). At first we present the principle of these methods Golomb Ruler and Costas array. Then we apply these two methods to normal Costas signal, modified Costas signal and step frequency modulation and calculate the AF for all. The results of comparison have shown that considerable reduction of side-lobes of AF is achieved by using these two methods, and consequently an improvement of AF is obtained.

A New Suggested Technique to Determine the Best Models for Time Series

The analysis of time series data is one of the most important statistical topics, usually focuses on forecasting the future behavior of the series at a certain time for certain purposes.