الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
This thesis is devoted to introduce a new pulse compression technique for high range resolution for modem radar systems. The implemented waveforms are simple and suitable for radar systems . The designed high range resolution is developed to be more accurate and suitable for a surveillance radar receivers. The basic concept of pulse compression technique is its capability to resolve two small targets that are located at long range with very small separation between them. These requires a radar system to transmit a long pulse which will have enough energy to detect a small target at long range. However, a long pulse degrades range resolution. Hence, frequency or phase modulation of the signal is used to achieve a high range resolution when a long pulse is required. The capabilities of short-pulse and high range resolution radar are significant. The proposed pulse compression technique introduces a new transmitted waveforms not only linear frequency modulation but also biphase coded” biphase coding linear frequency modulation” . These new codes introduce high compression ratio and minimum side lobe level using Genetic Algorithm .The proposed pulse compression technique is applied to the radar systems in order to improve its target range resolution capability .Linear frequency Modulation (LFM) waveform becomes widespread in modern pulse compression radar systems in order to improve its target range resolution capability. Conventional LFM based on varying the waveform frequency linearly within the radar pulse width which leads to high Auto Correlation Function (ACF) with limited compression ratio
CR) and side lobe level (SLL). This thesis proposes Optimized Biphase Pulse Compression Codes (OBPCC) with the LFM waveform. Frequency and phase coding have been used to a hieve optimum (SLL) and (CR) using Genetic algorithm (GA). The results compare the :\CF for both LFM and phase coded (PCLFM) are compared. Set of codes are generated for code length of 51 with frequency modulation index from 0.002 to 0.009. Peak sidelobe level -18.R9 dB to -19.33 dB is achieved. The results obtained show superiority of PCLFM °er the conventional LFM which improves the compression ratio by 9.95 times the _ nventional LFM.
This thesis is divided mainly into three sections. First section illustrates how the pulse pression techniques operate using the conventional methods and the types of radar ’eforms generation. Second section presents the main idea of the proposed compression ique and anew transmitted waveforms. The last one show the improvement and ement of the obtained resuits when compared with the traditional waveforms and ntional compression teclmique.