A functional test of 2-GHz/4-GHz RF digital communication device using digital tester

Recently, there is an increasing need for methods of functionally testing RF devices to provide lower cost alternatives to testing RF communication systems. In this paper, a real-time functional testing method of RF-ICs using a digital tester is proposed as an alternative to conventional RF testing. The method is based on a concept of direct modulation. By employing the proposed method, the QPSK and 16-QAM signals can be generated with digital tester drivers. The method can directly compare the baseband data with its expected data through digital tester comparators without demodulation. Therefore, the proposed method does not require any modulator or demodulator. Moreover, the method can perform both a stress test of RF receivers by injecting modulation error and a margin test of RF transmitters by using a dual-threshold comparator.