Ramachandran, MK and Surabhi, GD and Chockalingam, A (2020) OTFS: A New Modulation Scheme for High-Mobility Use Cases. In: Journal of the Indian Institute of Science, 100 (2). pp. 315-336.
|
PDF
jou_ind_sci_100-02_315-336_2020.pdf - Published Version Download (3MB) | Preview |
Abstract
Among the several emerging use case families in 5G, high-mobility use case family is a technologically challenging one. It is expected that there will be a growing demand for mobile services in vehicles, high-speed trains, and even aircraft. The degree of mobility support required (i.e., speed) will depend upon the specific use case (e.g., 500 km/h in bullet trains and 1000 km/h in airplanes). Mobility-on-demand, ranging from very high mobility to low or no mobility, need to be supported. The currently used waveforms fail to perform well in high-mobility scenarios where the Doppler shifts witnessed are quite high (e.g., several kHz of Doppler). Orthogonal time�frequency space (OTFS) is a recently proposed radio access technology waveform suited very well for high-mobility environments. It is a two-dimensional modulation scheme in which information symbols are multiplexed in the delay�Doppler domain. We present an overview of delay�Doppler representation of wireless channels and introduce OTFS modulation along with OTFS basis functions. We illustrate the slow variability and sparse nature of the delay�Doppler channel using an urban multi-lane scenario. Focusing on MIMO-OTFS systems, we present signal detection and channel estimation schemes and their performance. MIMO-OTFS is shown to achieve significantly better performance compared to MIMO-OFDM in high-Doppler environments operating in 4 GHz and 28 GHz frequency bands.
| Item Type: | Journal Article |
|---|---|
| Publication: | Journal of the Indian Institute of Science |
| Publisher: | Springer |
| Additional Information: | The copyright of this article belongs to Springer |
| Keywords: | Aircraft; MIMO systems; Modulation; Railroad cars; Railroad transportation; Railroads, Degree of mobility; Doppler channels; Frequency spaces; High speed train (HST); Information symbol; Radio access technologies; Two dimensional modulations; Wireless channel, 5G mobile communication systems |
| Department/Centre: | Division of Electrical Sciences > Electrical Communication Engineering |
| Date Deposited: | 12 Aug 2020 07:47 |
| Last Modified: | 12 Aug 2020 07:47 |
| URI: | http://eprints.iisc.ac.in/id/eprint/65439 |
Actions (login required)
 |
View Item |
