Data transmission for maritime and land mobiles using stored channel simulation

Channel simulators with synthetically generated complex multiplicative and additive Gaussian distortions are widely used for investigating non-frequency-selective fading channels. An alternative is to record the channel distortions (i.e. amplitude and phase variations) by probing the real channel and to use these stored signals to control the simulator in the lab. This stored channel method (SCM) has been applied to the following mobile radio channels • satellite to ship • SAR emergency buoy to satellite • base station to land mobile for low data rates A collection of tapes has been obtained for these channels under various conditions. They were used to compare several data transmission schemes at different data rates and various S/N-ratios, but with the same replayed fading fluctuations. The SCM was used to evaluate low rate data transmissions (< 10 Kbit/sec) with various modulation schemes such as CBPSK, digital FM, and DPSK/FM. Bit error rate results are presented. The experience with the SCM, its advantages and limitations are being discussed.