DFRC with Improved Communication-Sensing Trade-off via Private Subcarrier Permutations and Pairing with Antennas

TL;DR

This paper proposes a novel DFRC system using MIMO radar with sparse arrays, private subcarrier permutations, and antenna pairing to improve the communication-sensing trade-off, achieving higher efficiency and performance.

Contribution

It introduces private subcarrier permutation and pairing strategies in OFDM-based MIMO DFRC systems to enhance the communication-sensing balance and proposes a low complexity detection algorithm.

Findings

Improved communication rate through subcarrier sharing and pairing.

Enhanced sensing performance via larger virtual array formation.

Effective private subcarrier detection with low complexity algorithm.

Abstract

Dual function radar communication (DFRC) systems can achieve significant improvements in spectrum efficiency, system complexity and energy efficiency, and are attracting a lot of attention for next generation wireless system design. This paper considers DFRC systems using MIMO radar with a sparse transmit array, transmitting OFDM waveforms, and assigning shared and private subcarriers to active transmit antennas. Subcarrier sharing allows antennas to modulate data symbols onto the same subcarriers and enables high communication rate, while the use of private subcarriers trades-off communication rate for sensing performance by enabling the formulation of a virtual array with larger aperture than the physical receive array. We propose to exploit the permutation of private subcarriers among the available subcarriers and the pairing between active antennas and private subcarriers to recover some of the communication rate loss. Exploiting the $1$-sparse property of private subcarriers, we also propose a low complexity algorithm to identify private subcarriers and detect the antenna-subcarrier pairing.