Testing ourselves [The quiz for this issue]

A senior antenna engineer is going to calibrate a new open-field test site (OFTS). His mission is to make this open-field test site ready as soon as possible, for antenna and EMC measurements and tests. If you were the engineer, how would you proceed? Which standards would you use in the calibration, and why? How do you calibrate an open-field test site? The engineer realized that highly integrated wireless communication systems require RF system design with modular and universal components. He has been witnessing the transformation from almost fully electronic RF systems (e.g., heterodyne receivers) to fully software-controlled systems (e.g., software radio and radar), with minimum analog circuitry, for some time. All he needs today is a suitable antenna, plus an analog-to-digital (ADC) or digital-toanalog (DAC) converter; the rest is handled via computers. He is going to design a DAC with certain given characteristics. Six questions are posed about the design.