New-Tech Europe | March 2017 | Digital Edition

result from an ECM system due to resampling at a different rate, a small number of effective bits in the ADC, phase noise or amplifier distortions in the target simulator. When using a DRFM, the generated echo signal fidelity will likely be different than one from a real target. The radar processes focused on electronic protection can detect the differences from the returned echo with different fidelity. This measurement can also be assessed by the presented radar target generator. Such demonstrations show clearly that COTS test and measurement systems address the test and measurement of radars. In addition, COTS test and measurement equipment is able to generate also radar echo signals with variable range, radial velocity and radar cross section. This combination makes state of the art test equipment very valuable and efficient instruments for radar test. References [1] Small Business Innovation Research (SBIR), Navy, Topic N131-006, Acquisition Program, "Direct Digital Radio Frequency (RF) Conversion Digital Radio Frequency Memory (DRFM)", 2013 [2] Heuel, S.; Roessler, A., "Co- existence Tests for S-Band Radar and LTE Networks", Microwave Journal - Military Microwaves, August 2014. [3] Reuters, "Jets vanishing from Europe radar linked to war games", retrieved from http://www. reuters.com/article/2014/06/13/ u s - e u r o p e - a i r p l a n e s - s a f e t y - i d U S K B N 0 E O 1 CW2 0 1 4 0 6 1 3 , November 2014

Fig. 4: Single target generated by the COTS radar target generator

targets at user definable ranges and radial velocities. The signal generator also has multiple RF sources, making it possible to test radar against interference, as for example co-existence with Long Term Evolution (LTE) or other radio-based services [2]. One can also generate arbitrary waveform files and transmit these additional disturbing signals towards the radar in order to test adaptive algorithms like “constant false alarm rate” (CFAR) or other land / sea clutter mitigation techniques. In addition to testing the functional

performance of the radar, the COTS target generator can help assess modern electronic protection measures in the radar, helping to prevent incidents such as the disappearance of aircraft from air traffic control radar caused by military electronic warfare exercises [3]. To test the performance of the radar signal processing a radar waveform is transmitted, delayed and disturbed in the radar target simulator. The radar receiver can tell whether or not the echo return was virtual or real using correlation filters. An uncorrelated signal might

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