Design of a Coherent Generation and Acquisition System at 1,2GHz

This paper describes the work made at INTA´s Radar Laboratory on a module dedicated to signal generation, data acquisition / filtering, and timing as part of a synthetic aperture radar (SAR) developed at INTA. During transmission this module is able to feed the DAC´s at 1,2 GSamples/s to generate the baseband signals in quadrature. During reception, the acquired data is filtered (with a variable length filter which depends on the decimation to be applied later) and stored in memory at the same sampling rate. These operations are controlled by a timing block, which has the responsibility for trigger activation at the precise time. Finally, the module has to synchronize the clocks coming from DAC, ADC and the proper FPGA clock, in order to obtain a coherent system operation.