【摘 要】
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The application of the orthogonal time frequency space (OTFS) modulation in multiple-antenna systems is investigated. The diversity and/or the multiplexing gain can be achieved by deploying various multiple-antenna techniques, and thus the reliability and
【机 构】
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State Key Laboratory of Rail Traffic Control and Safety,Beijing Jiaotong University,Beijing 100044,C
论文部分内容阅读
The application of the orthogonal time frequency space (OTFS) modulation in multiple-antenna systems is investigated. The diversity and/or the multiplexing gain can be achieved by deploying various multiple-antenna techniques, and thus the reliability and/or the spectral efficiency are improved correspondingly. We provide two classes of OTFS- based multiple-antenna approaches for both the open-loop and the closed-loop systems. Spe?cifically, in the open-loop system, a transmitting diversity approach, which resembles the space-time coding technique, is proposed by allocating the information symbols appropriate?ly in the delay-Doppler domain. In the closed-loop system, we adopt the Tomlinson-Harashi?ma precoding in our derived delay-Doppler equivalent transmission model. Numerical evalu?ations demonstrate the advantages of applying the multiple-antenna techniques to the OTFS. At last, several challenges and opportunities are presented.
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