In this paper, we like to propose a high throughput mobile communication system that can work even at the very high vehicular speed. Generally, mobility and data throughput has inverse relationship. Also, very complicated receiver structure is required and takes a long time processing for compensating the Doppler frequency due to the high speed mobility. Seriously, the communication performance becomes degraded with the increase of the dimension of multiple input and multiple output (MIMO), since the delay Doppler problem becomes bigger the higher dimension of MIMO. So, it is greatly important to design the very robust mobile communication that can provide the high throughput even at the very high vehicular speed system. Design and performance evaluation of the orthogonal time frequency space (OTFS) modulation system and OTFS-based MIMO system are described and analyzed at the very high mobility environment. OTFS modulation can concisely compensate the delay-Doppler spreading effect by using two dimensional inverse discrete Fourier transform and discrete Fourier transform operation. It enables OTFS system to transmit high-speed data. Especially, OTFS-MIMO system can transmit data stream of each antenna without the communication performance degradation even in the high Doppler frequency environments. As simulation results, it is confirmed that the capacity of 1 × 1 OTFS system is a similar to each stream of 2 × 2 OTFS-MIMO system. That is, 2 × 2 MIMO system can completely double the communication capacity in comparison with 1 × 1 OTFS system even in the very high Doppler frequency channel such as high speed mobile environments. This remarkable performance can continue in the very high dimensional MIMO system and simultaneously in the high mobility situation.
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