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DOE OSTI · 1819951

Multi-User Capacity for Cyclic Prefix Direct Sequence Spread Spectrum with Linear Detection and Precoding

Kenney, Brent A.·Majid, Arslan J·Moradi, Hussein·Farhang-Boroujeny, Behrouz
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Abstract

Cyclic Prefix Direct Sequence Spread Spectrum (CP-DSSS) is a promising solution for futuristic 6G ultra-reliable low latency communications (URLLC) and massive machine type communication (mMTC) applications, where the CP-DSSS waveform would operate as a secondary network at the same frequencies as the primary network but at much lower SNR. In this paper, we show per-user capacity for multi-user scenarios, where simple matched filtering (MF) is performed on the uplink (UL) and time-reversal (TR) precoding is used on the downlink (DL). When operating in the low SNR regime, CP-DSSS achieves per-user capacity near the optimum single-user capacity by using a MF detector at the receiver for the UL. TR precoding converges to the optimal capacity as the number of antennas at the hub/gateway increases. Given the near-optimal performance of MF detection and TR precoding for each of the users, CP-DSSS can be implemented with simple device transceiver structures, reducing per-unit cost for massively deployed 6G networks.

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5G and Beyond Communications99 GENERAL AND MISCELLANEOUSCapacityCP-DSSSFilter-bank Multi-Carrier Spread Spectrum SystemInternet of ThingsMassive Machine-Type CommunicationsMulti-User Access ControlWireless Communications

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Kenney, Brent A., Majid, Arslan J, Moradi, Hussein, Farhang-Boroujeny, Behrouz. 2021-02-15. Multi-User Capacity for Cyclic Prefix Direct Sequence Spread Spectrum with Linear Detection and Precoding. https://www.osti.gov/biblio/1819951

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