Low Complexity ICI Mitigation in OFDM Based RadCom Systems

MIMO-OFDM Joint Radar-Communications: Is ICI Friend or Foe?

“…To tackle the more practical scenarios of multiple targets, recent works investigate range-velocity estimation techniques for multiple objects in the presence of ICI [12], [16], [21]. Under the assumption that the number of targets is known apriori, an alternating maximization approach that takes ICI into account is proposed in [12] to reduce the complexity of highdimensional maximum-likelihood (ML) search.…”

“…In [16], the ICI effect is eliminated via an all-cell Doppler correction (ACDC) method, which performs Doppler compensation for arbitrary velocities with a precision on the level of Doppler resolution. Following a similar line of reasoning, the work in [21] develops a sparsity based ICI removal and range-velocity estimation algorithm. For proper functioning of the methods in [16], [21] in terms of ICI compensation, a common requirement is that OFDM symbol matrix should be rank-one (i.e., same symbols repeated over time).…”

“…Following a similar line of reasoning, the work in [21] develops a sparsity based ICI removal and range-velocity estimation algorithm. For proper functioning of the methods in [16], [21] in terms of ICI compensation, a common requirement is that OFDM symbol matrix should be rank-one (i.e., same symbols repeated over time).…”

“…The prior approaches to OFDM radar sensing in the presence of ICI [12], [16], [17], [19]- [21] suffer from several major drawbacks that can significantly limit their applicability in practical JRC scenarios. First, most of the existing ICI compensation methods focus exclusively on the radar functionality of OFDM and impose strict constraints on transmit data symbols, such as cyclic shift property [19], good correlation characteristics [17], [19], identical sequences across subcarriers [20] and rank-one frequency-time OFDM symbol matrix [16], [21].…”

“…The prior approaches to OFDM radar sensing in the presence of ICI [12], [16], [17], [19]- [21] suffer from several major drawbacks that can significantly limit their applicability in practical JRC scenarios. First, most of the existing ICI compensation methods focus exclusively on the radar functionality of OFDM and impose strict constraints on transmit data symbols, such as cyclic shift property [19], good correlation characteristics [17], [19], identical sequences across subcarriers [20] and rank-one frequency-time OFDM symbol matrix [16], [21]. Such constraints, however, would lead to a substantial loss in communications data rate (e.g., M times reduction in data rate [16], [21], where M is the number of OFDM symbols) and essentially impede dual-functional operation, which is one of the core properties of OFDM.…”