[Society of Exploration Geophysicists and and Chinese Geophysical Society International Workshop and Gravity, Electrical & Magnetic Methods and their Applications, Chenghu, China, 19-22 April 2015 - Chenghu, China (19 April to 22 April)] International Workshop and Gravity, Electrical & Magnetic Methods and their Applications, Chenghu, China, 19-22 April 2015 - Cascaded transmitter with output of 2n sequence pseudo-random waveform for semi-airborne frequency-domain electromagnetic exploration