Radar waveform synthesizer is a key component in radar system as it determines the best achievable resolution. A popular approach in radar waveform synthesis is the Direct Digital Synthesis approach where the signal is first generated in digital domain and converted into analog signal using a High Speed Digital-to-Analog Converter (HS-DAC). In this paper, a miniature and low cost radar waveform synthesizer is proposed. The synthesizer is targeted for Unmanned Aerial Vehicle (UAV) based radar system applications that require miniaturized equipment due to limited space in aircraft's fuselage. The signal synthesizer has been developed using Altera DE3 development board (Stratix III FPGA) and a custom made dual-channel 420 MSPS HS-DAC board. The proposed system is capable of generating various types of radar waveforms: a) Linear Frequency Modulated (LFM) or chirp pulse, b) Frequency Modulated Continuous Wave (FMCW), and c) Calibration Tone (Cal-Tone), for use in different types of radar applications. The distinguishing feature of the proposed synthesizer is its capability in reconfiguring the signal properties in real-time. The performance of the synthesizer has been benchmarked with commercially available radar waveform signal synthesizer and comparable performance has been observed.
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