New-Tech Europe | Oct 2016 | Special Edition For Electronica 2016

azimuth and range in a radar scan conversion application. Target Simulator We can conduct proper functional test of an Rx through target simulation using the VSG based on sync pulses. In this case, the ATE acts as a target signal generator coming from the antenna. Each interrogation is synchronized by a trigger pulse connected to both the VSG trigger and the FPGA. Users can configure the range and azimuth to simulate with the target. When a target is ready for simulation, the VSG generates the reply RF pulses of a target after the azimuth count is reached in the FPGA and the next sync trigger is received from the radar. The user can select reply code and mode, and scripted pulses are generated at the specified range and azimuth. Targets are simulated for stationary and trajectory motion. A user configures moving paths at different trajectories. The system can simulate multiple targets at different ranges and azimuths from the same VSG. Different code patterns are applied to the reply pulses as specified by the user. Reply pulses are a sequence of pulses spaced 1 µs apart with a pulse width of 450 ns. Each target’s replies are framed with F1 and F2 pulses at the beginning and end of the sequence. The number of pulses in a frame is derived by the mode of interrogation selected in the GUI. Each sync pulse can have a different mode of reply based on the interrogation mode selected. Such three-reply pulses are separately configurable and can be generated through the VSG with reference to each sync pulse. Figure 5 illustrates reply pulse generation with range delay, azimuth, and

Figure 5- Pulse Formats

Figure 6- Sequence of Tests

video signals from the radar in the TTL format through the FPGA board. The reply pulses from the target are demodulated in the

code simulation.

Radar Scan Converter The system acquires and processes

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