First experiments based on a highly digitized radar

In the last years technological progress in analog to digital (ADC) and digital to analog converters (DAC) has been substantial. Particularly, the analog bandwidth has increased to a level where many new applications in radar techniques become possible. A major goal is to shift the boundary between analog and digital parts of a remote sensing system like radar further towards the antenna in order to reduce drift and non-linearity effects, and to gain a higher flexibility in signal processing. A high-resolution digital beam-forming (DBF) system requires adequately sampled, stored, and finally processed signals of several receiver channels. For multi-channel systems, especially in the transmit part, one main drawback is the interference between simultaneously transmitted signals being operated in the identical frequency range. However, the use of coded signals can overcome this issue. Currently we are investigating a radar architecture that uses major digital parts, multiple receive and transmit channels, and a wide bandwidth for high resolution imaging. The innovative radar system is called Gigarad. In this paper a very first experimental setup of Gigarad is outlined. Several coded waveforms have been analyzed with respect to their cross-correlation properties and their range resolution performance. First measurement results for a few selected waveforms are presented.