REVIEW 2 major objections 5 minor 4 cited by
Doubly-Dispersive MIMO Channels with Stacked Intelligent Metasurfaces: Modeling, Parametrization, and Receiver Design
T0 review · 2 major / 5 minor · reviewed 2026-08-10 · deepseek-v4-flash
Pith's one-line read The paper introduces a unified metasurfaces-parametrized doubly-dispersive MIMO channel model that covers OFDM, OTFS, and AFDM, and shows that optimized stacked intelligent metasurfaces reduce bit-error rates and narrow the performance…
desk verdict A solid modeling extension of SISO DD waveforms to SIM/RIS MIMO, but the SIM-optimization surrogate ignores delay-Doppler structure, so the reported BER gains need an additional argument. read the letter →
The pith
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
The reading
What carries the argument
The load-bearing machinery is the Kronecker-sum factorization of the effective channel into a small spatial matrix $\check{\mathbf{H}}_p$, built from SIM transfer functions, diffraction coefficients, array responses, and beamformers, and a per-path time-frequency matrix $\mathbf{G}_p = \boldsymbol{\Theta}_p \boldsymbol{\Omega}^{f_p} \boldsymbol{\Pi}^{\ell_p}$ that encodes the delay and Doppler of each path. Each waveform's effective matrix is obtained by conjugating $\mathbf{G}_p$ with its own transform: the DFT for OFDM, the discrete Zak transform for OTFS, and the discrete affine Fourier transform for AFDM, yielding the same structural form in the effective channel equations. The same factorization lets the SIM phase gradients factor through the SIM layers, giving closed-form gradients that drive the steepest-ascent optimization of the SIM phase configurations.
What would settle it
Take a fixed MPDD channel realization, run the SIM phase optimization, then randomly permute the delay and Doppler phases of the paths while keeping their amplitudes and the total channel power fixed, and measure BER for OFDM, OTFS, and AFDM; if BER follows the optimized objective rather than the permutation, the power surrogate is supported, and if not, the reported gains depend on an artifact of the objective.
Extended reading notes
Core claim
The paper's central discovery is an end-to-end channel model in which the doubly dispersive MIMO channel factorizes as $\mathbf{H}(Z, \tilde{Z}, \mathcal{F}, t, \tau) = \boldsymbol{\Upsilon}_R(\tilde{Z}) \mathbf{R}_{RX}^{1/2} \tilde{\mathbf{H}}(\mathcal{F}, t, \tau) \mathbf{R}_{TX}^{1/2} \boldsymbol{\Upsilon}_T(Z)$, with $\boldsymbol{\Upsilon}_T$ and $\boldsymbol{\Upsilon}_R$ the diffraction-based transfer matrices of the transmit and receive SIMs, $\mathbf{R}_{TX}$ and $\mathbf{R}_{RX}$ spatial correlation matrices, and $\tilde{\mathbf{H}}$ the RIS-parametrized delay-Doppler channel containing direct and reflected paths. From that factorization, the effective OFDM, OTFS, and AFDM channel matrices all take the form $\bar{\mathbf{H}} = \sum_p \check{\mathbf{H}}_p^d \otimes \mathbf{G}_p^{\text{waveform}} + \sum_{k,\bar{p},\tilde{p}} \check{\mathbf{H}}_{k,\bar{p},\tilde{p}}^{\text{RIS}} \otimes \mathbf{G}_{k,\bar{p},\tilde{p}}^{\text{waveform}}$, so the waveform-specific linear transforms, namely the DFT, the discrete Zak transform, and the discrete affine Fourier transform, act only on the per-path delay-Doppler matrices. The paper argues this structure makes waveform comparison and unified receiver design straightforward, and its numerical study shows that optimizing the SIM phase layers with the proposed gradient ascent, followed by its Gaussian belief propagation detector, lowers bit-error rate for all three waveforms and narrows the gap between OFDM and the more sophisticated OTFS and AFDM.
Load-bearing premise
The load-bearing premise is that maximizing the sum of per-path channel-matrix powers in the optimization objective, an objective the paper notes is not affected by delay or Doppler phases, is a valid proxy for lowering bit error rate in a doubly dispersive channel.
Editorial extensions
If this is right
- If the model is correct, channel estimation, equalization, and detection blocks designed for the MPDD matrix $\bar{\mathbf{H}}$ transfer directly between OFDM, OTFS, and AFDM, since only the $\mathbf{G}_p$ block changes.
- Programmable SIMs become a physical-layer resource that can be optimized separately from digital beamformers, augmenting rather than replacing conventional MIMO processing.
- With optimized SIMs, OFDM's bit-error rate approaches that of OTFS and AFDM in doubly dispersive channels, so waveform choice matters less when the propagation environment can be programmed.
- Increasing the number of SIM layers or receive antennas both improve bit-error rate, and the gains come from passive wave-domain processing rather than increased transmit power, since the compared channels are power-normalized.
- The proposed receiver achieves near-LMMSE bit-error rate with per-iteration complexity linear in the number of channel coefficients, avoiding matrix inversion.
Reading between the lines
- The paper's own footnote notes that the optimization objective is blind to delay and Doppler phases; a natural extension is to insert those phases into the objective and test whether dispersion-aware SIM tuning yields larger gains than the power-based tuning reported here.
- Because the delay-Doppler blocks carry radar-relevant parameters, the MPDD model is a ready-made input-output model for metasurface-aided integrated sensing and communications, even though sensing-specific estimation is left for future work.
- The same factorization likely applies to other doubly dispersive-friendly waveforms such as OCDM and ODDM by substituting their transform for $\mathbf{G}_p$, so the model may serve as a generic DD-waveform testing platform.
- The reported SISO and SIMO bit-error gains suggest a testable field experiment: with fixed total channel power, compare BER for OFDM with and without optimized SIM phases on the same measured doubly dispersive link; if the gains persist, the passive lensing effect is real.
Signed reviews
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The manuscript introduces a metasurface-parametrized doubly-dispersive (MPDD) MIMO channel model in which a transmit ULA is preceded by a stacked intelligent metasurface (SIM), a receive SIM is placed before the receive ULA, and K reconfigurable intelligent surfaces (RISs) are placed in the propagation environment. The end-to-end channel is written as H = Υ_R R_RX^{1/2} (H_d + Σ_k H_RX,k Φ_k H_k,TX) R_TX^{1/2} Υ_T, where each constituent channel is a sum of delay-Doppler paths with UPA steering matrices. The authors derive a discrete-time input-output relation, then specialize it to OFDM, OTFS, and AFDM effective channel matrices. As an application, they optimize the TX/RX SIM phase shifts by gradient ascent on a sum of per-path Frobenius norms, propose a GaBP detector, and report BER simulations showing performance gains with optimized SIMs.
Significance. If the modeling part is correct, the paper offers a useful unified framework for analyzing delay-Doppler MIMO channels with programmable metasurfaces, and the closed-form gradient expressions plus the linear-complexity GaBP detector are attractive practical ingredients. The derivation is detailed and builds on independently published SISO and SIM models, so the central channel-modeling contribution is credible under the stated hardware assumptions. However, the numerical demonstration that optimized SIMs reduce BER rests on a surrogate objective that is explicitly independent of delay-Doppler effects, and the connection from that objective to the reported BER gains is not established. The modeling contribution can stand alone, but the headline performance claim needs additional support before the paper can be accepted.
major comments (2)
- [V-A, V-D, Fig. 3] The optimization objective in Eq. (44) is a sum of per-path Frobenius norms of the static spatial matrices, i.e., it contains only the factors multiplying the waveform-specific delay-Doppler matrices G_p and G_{k,bar p,tilde p} in Eqs. (30), (36), and (42). It omits the CP-phase, Doppler, and cyclic-delay matrices Θ_p, Ω^{f_p}, and Π^{ell_p}. Footnote 11 explicitly states that the objective is "not impacted by DD effects." Section V-D then normalizes all effective channels so that their Frobenius norms are equal. Therefore the BER gains in Fig. 3 can only come from reshaping the delay-Doppler structure or the relative weighting of paths, yet no analysis or ablation shows that the power-only objective is a reliable surrogate for such reshaping. Please add a waveform-aware objective (e.g., one that includes the G_p factors) or a control experiment with random or fixed phase configurations under the same Frobenius-norm normalization, and explain the mechanism by which per-path spatial power focusing improves GaBP detection in a doubly dispersive channel.
- [V-A, Eqs. (49)-(54)] The index ranges in the gradient derivations are difficult to follow and should be verified. For example, the product in Eq. (49) runs over q' = 1 to q+1 with terms Ψ_{Q-q'+1}Γ_{Q-q'+1}, which, for small Q, does not obviously isolate the layer Ψ_q that is being differentiated; the definitions of S_q and S_tilde_q in Eqs. (50) and (54) are likewise non-obvious. Since the gradient updates in Algorithm 1 drive the headline performance results, a worked small-Q example or a corrected index range would remove any doubt about the correctness of the optimization procedure.
minor comments (5)
- [IV-E] The statement that "unoptimized SIMs have no effect onto the DD channels" should be qualified: even with Ψ_q = I, the transfer matrices Υ_T and Υ_R in Eqs. (6)-(7) contain the diffraction matrices Γ_q, which are not identity and therefore change the channel relative to a system with no SIMs. If the comparison with [8] is made after some normalization or calibration, that procedure should be stated explicitly.
- [V-B] There is a typo in the sentence "It be shown here that SIMs can significantly lower the performance gap" and a grammatical error in "the design of waveforms suitable to mitigating" later in the same paragraph; both should be corrected.
- [V-D] The simulation setup for Fig. 3 is not fully reproducible: the text specifies N, K, K', P, N_T, and N_R, but not the CP length, the maximum delay and Doppler values used to generate the random paths, the GaBP iteration count, the gradient-ascent iteration count, or the learning-rate schedule. Please add these settings either in the text or in the figure captions.
- [Footnote 11] Footnote 11 contains grammatical errors ("significantly improvement" and "described by in Section IV") and, more importantly, asserts that the DD-agnostic nature of the optimization "further validates the overall contribution" without explaining why that follows; the sentence should be rewritten to state the intended implication clearly.
- [Eq. (18)] For the record, I checked the cascaded-path normalization in Eq. (18): the factor J√(M M̃/(P̄ P̃)) is the product of the normalization constants of Eqs. (15) and (16), so I do not find a missing square root there.
Circularity Check
No circular derivation: the MIMO-SIM channel model is a new combination of independently published prior models, and the eq. (44) SIM-optimization surrogate is a validity concern, not a circular reduction.
full rationale
The derivation chain is: (i) adopt the SIM transfer functions and Rayleigh-Sommerfeld diffraction coefficients from [54]; (ii) adopt the SISO doubly-dispersive waveform channel matrices G_p, G_p^{OFDM}, G_p^{OTFS}, G_p^{AFDM} from [8]; (iii) form the MIMO effective channels through Kronecker products with the spatial path matrices in eqs. (24), (30), (36), and (42). Each cited component is an external, published result with its own derivation, and neither is fitted to the data or conclusions of the present paper. The end-to-end MPDD channel in eq. (11) is a new composition of these independently grounded pieces, not a renaming or a restatement of the inputs. The BER simulations in Fig. 3 are computed from the full delay-Doppler effective channels, not from the optimization objective itself. Footnote 11 admits that the eq. (44) objective is "not impacted by DD effects"; this is a surrogate-validity limitation that may weaken the strength of the headline BER gains, but it is not circularity because the SIM phases are optimized against a power objective and the reported BER is then obtained from the complete OFDM, OTFS, and AFDM channel matrices. There is no fitted parameter renamed as a prediction and no self-citation chain that forces the claimed conclusion. The normalization in Section V-D equalizes Frobenius norms and is explicitly done to the disadvantage of the proposed scheme, so it cannot manufacture the gains by construction. The self-citations to [8] and [54] are normal, non-circular reliance on prior work.
Assumptions & free parameters
free parameters (4)
- AFDM chirp parameter c1 =
not specified
- AFDM chirp parameter c2 =
not specified
- SIM optimization hyperparameters (learning rate schedule, damping factor beta_x, iteration counts) =
not reported
- Effective channel power normalization =
equal Frobenius norms across all waveforms and SIM configurations
assumptions (5)
- domain assumption The SISO doubly dispersive I/O structure from [8], including CP and CPP matrices Theta_p and waveform-specific G_p matrices, remains valid when SIMs and RISs are inserted.
- domain assumption Each SIM layer and RIS is an ideal diagonal phase-only surface whose meta-atoms have no amplitude, frequency, or mutual-coupling response.
- domain assumption Inter-layer propagation in SIMs follows the Rayleigh-Sommerfeld diffraction coefficients in eqs. (5) and (8), with the stated layer distances and meta-atom spacings.
- domain assumption Spatial correlation at the SIM outer layers is described by the sinc-based matrices R_TX and R_RX from [54].
- domain assumption The channel gains, delays, Doppler shifts, and angles are generated from the stated distributions and remain constant over one coherent block.
Cite this review
Pith. "Pith review of Doubly-Dispersive MIMO Channels with Stacked Intelligent Metasurfaces: Modeling, Parametrization, and Receiver Design." pith.science (2026). https://pith.science/paper/7NY77JAC
@misc{pith2026250107724,
author = {Pith},
title = {Pith review of: Doubly-Dispersive MIMO Channels with Stacked Intelligent Metasurfaces: Modeling, Parametrization, and Receiver Design},
year = {2026},
howpublished = {\url{https://pith.science/paper/7NY77JAC}},
note = {Machine review of arXiv:2501.07724}
}
read the original abstract
Introduced with the advent of statistical wireless channel models for high mobility communications and having a profound role in communication-centric (CC) integrated sensing and communications (ISAC), the doubly-dispersive (DD) channel structure has long been heralded as a useful tool enabling the capture of the most important fading effects undergone by an arbitrary time-domain transmit signal propagating through some medium. However, the incorporation of this model into multiple-input multiple-output (MIMO) system setups, relying on the recent paradigm-shifting transceiver architecture based on stacked intelligent metasurfaces (SIM), in an environment with reconfigurable intelligent surfaces (RISs) remains an open problem due to the many intricate details that have to be accounted for. In this paper, we fill this gap by introducing a novel DD MIMO channel model that incorporates an arbitrary number of RISs in the ambient, as well as SIMs equipping both the transmitter and receiver. We then discuss how the proposed metasurfaces-parametrized DD (MPDD) channel model can be seamlessly applied to waveforms that are known to perform well in DD environments, namely, orthogonal frequency division multiplexing (OFDM), orthogonal time frequency space (OTFS), and affine frequency division multiplexing (AFDM), with each having their own inherent advantages and disadvantages. An illustrative application of the programmable functionality of the proposed model is finally presented to showcase its potential for boosting the performance of the aforementioned waveforms. Our numerical results indicate that the design of waveforms suitable to mitigating the effects of DD channels is significantly impacted by the emerging SIM technology.
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Forward citations
Cited by 4 Pith papers
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Metasurfaces-Integrated Doubly-Dispersive MIMO: Channel Modeling and Optimization
A unified doubly-dispersive MIMO channel model with SIM and RIS is derived, and SIM phase optimization is shown to improve BER and radar parameter estimation for OFDM, OTFS, and AFDM.
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Parametrized Stacked Intelligent Metasurfaces for Bistatic Integrated Sensing and Communications
A bistatic ISAC system with sensing-optimized stacked intelligent metasurfaces achieves large gains in range/velocity estimation and bit error rate over a no-metasurface baseline across OFDM, OTFS, and AFDM waveforms.
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Flexible Intelligent Metasurfaces in High-Mobility MIMO Integrated Sensing and Communications
A flexible-intelligent-metasurface-parameterized doubly dispersive MIMO channel model is proposed, and optimizing the surface shape at both link ends is shown by simulation to improve achievable rate and angle-of-arri...
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Indoor Channel Characterization with Extremely Large Reconfigurable Intelligent Surfaces at $300$ GHz
A 100x100 two-bit RIS at 304 GHz can be modeled as three discrete rays, and its far-field approximation holds at roughly one fifth of the textbook far-field distance.
Reference graph
Works this paper leans on
-
[8]
H. S. Rou, G. T. F. de Abreu, J. Choi, D. Gonz ´alez G., M. Kountouris, Y . L. Guan, and O. Gonsa, “From Orthogonal Time–Frequency Space to Affine Frequency-Division Multiplexing: A Comparative Study of Next- Generation Waveforms for Integrated Sensing and Communications in Doubly Dispersive Channels,” IEEE Signal Process. Mag., vol. 41, no. 5, 2024
work page 2024
-
[1]
Vehicle- to-Everything (V2X) Services Supported by LTE-Based Systems and 5G,
S. Chen, J. Hu, Y . Shi, Y . Peng, J. Fang, R. Zhao, and L. Zhao, “Vehicle- to-Everything (V2X) Services Supported by LTE-Based Systems and 5G,” IEEE Commun. Stand. Mag. , vol. 1, no. 2, 2017
work page 2017
-
[2]
6G Internet of Things: A Comprehensive Survey,
D. C. Nguyen, M. Ding, P. N. Pathirana, A. Seneviratne, J. Li, D. Niyato, O. Dobre, and H. V . Poor, “6G Internet of Things: A Comprehensive Survey,” IEEE Internet Things J. , vol. 9, no. 1, 2022
work page 2022
-
[3]
OTFS Enabled LEO Satellite Communications: A Promising Solution to Severe Doppler Effects,
J. Shi, Z. Li, J. Hu, Z. Tie, S. Li, W. Liang, and Z. Ding, “OTFS Enabled LEO Satellite Communications: A Promising Solution to Severe Doppler Effects,” IEEE Network , vol. 38, no. 1, 2024
work page 2024
-
[4]
Mobility Support for Millimeter Wave Communications: Opportunities and Challenges,
J. Li, Y . Niu, H. Wu, B. Ai, S. Chen, Z. Feng, Z. Zhong, and N. Wang, “Mobility Support for Millimeter Wave Communications: Opportunities and Challenges,” IEEE Commun. Surveys Tuts. , vol. 24, no. 3, 2022
work page 2022
-
[5]
Performance Degradation of OFDM Systems due to Doppler Spreading,
T. Wang, J. Proakis, E. Masry, and J. Zeidler, “Performance Degradation of OFDM Systems due to Doppler Spreading,” IEEE Trans. Wireless Commun., vol. 5, no. 6, 2006
work page 2006
-
[6]
Orthogonal Time-Frequency Signal- ing over Doubly Dispersive Channels,
K. Liu, T. Kadous, and A. Sayeed, “Orthogonal Time-Frequency Signal- ing over Doubly Dispersive Channels,” IEEE Trans. Inf. Theory , vol. 50, no. 11, 2004
work page 2004
-
[7]
D. W. Bliss and S. Govindasamy, Dispersive and Doubly Dispersive Channels, Cambridge University Press, 2013
work page 2013
Show all 76 references
-
[9]
On the Di- versity of Uncoded OTFS Modulation in Doubly-Dispersive Channels,
G. D. Surabhi, R. M. Augustine, and A. Chockalingam, “On the Di- versity of Uncoded OTFS Modulation in Doubly-Dispersive Channels,” IEEE Trans. Wireless Commun. , vol. 18, no. 6, 2019
2019
-
[10]
A Robust Baseband Transceiver Design for Doubly-Dispersive Channels,
R. Bomfin, M. Chafii, A. Nimr, and G. Fettweis, “A Robust Baseband Transceiver Design for Doubly-Dispersive Channels,”IEEE Trans. Wire- less Commun. , vol. 20, no. 8, 2021
2021
-
[11]
Estimation of Doubly-Dispersive Channels in Linearly Precoded Multicarrier Systems using Smoothness Regularization,
A. Pfadler, T. Szollmann, P. Jung, and S. Sta ´nczak, “Estimation of Doubly-Dispersive Channels in Linearly Precoded Multicarrier Systems using Smoothness Regularization,” IEEE Trans. Wireless Commun. , vol. 23, no. 2, 2024
2024
-
[12]
Two-Dimensional Delay-Doppler Pilots and Channel Estimation for Multi-Antenna OTFS in Doubly Dispersive Channels,
Y . Liang, P. Fan, Q. Wang, and X. He, “Two-Dimensional Delay-Doppler Pilots and Channel Estimation for Multi-Antenna OTFS in Doubly Dispersive Channels,” IEEE Trans. Wireless Commun. , vol. 23, no. 7, 2024
2024
-
[13]
Novel OCDM Transceiver Design for Doubly-Dispersive Channels,
H. Haif, S. E. Zegrar, and H. Arslan, “Novel OCDM Transceiver Design for Doubly-Dispersive Channels,” IEEE Trans. V eh. Technol. , vol. 73, no. 8, 2024
2024
-
[14]
Multiuser Associ- ation and Localization over Doubly Dispersive Multipath Channels for Integrated Sensing and Communications,
H. Zhang, S. Chen, W. Meng, J. Yuan, and C. Li, “Multiuser Associ- ation and Localization over Doubly Dispersive Multipath Channels for Integrated Sensing and Communications,” IEEE J. Sel. Areas Commun. , vol. 42, no. 10, 2024
2024
-
[15]
Integrated Sensing and Communications: Toward Dual- Functional Wireless Networks for 6G and Beyond,
F. Liu, Y . Cui, C. Masouros, J. Xu, T. X. Han, Y . C. Eldar, and S. Buzzi, “Integrated Sensing and Communications: Toward Dual- Functional Wireless Networks for 6G and Beyond,” IEEE J. Sel. Areas Commun., vol. 40, no. 6, 2022
2022
-
[16]
Integrated Sensing and Communications with Recon- figurable Intelligent Surfaces: From Signal Modeling to Processing,
S. P. Chepuri, N. Shlezinger, F. Liu, G. C. Alexandropoulos, S. Buzzi, and Y . C. Eldar, “Integrated Sensing and Communications with Recon- figurable Intelligent Surfaces: From Signal Modeling to Processing,” IEEE Signal Process. Mag. , vol. 40, no. 6, Sep. 2023
2023
-
[17]
The Integrated Sensing and Communication Revolution for 6G: Vision, Techniques, and Applications,
N. Gonz ´alez-Prelcic, M. F. Keskin, O. Kaltiokallio, M. Valkama, D. Dardari, X. Shen, Y . Shen, M. Bayraktar, and H. Wymeersch, “The Integrated Sensing and Communication Revolution for 6G: Vision, Techniques, and Applications,” Proc. IEEE, early access, 2024
2024
-
[18]
In- Band Full-Duplex MIMO Systems for Simultaneous Communications and Sensing: Challenges, Methods, and Future Perspectives,
B. Smida, G. C. Alexandropoulos, T. Riihonen, and M. A. Islam, “In- Band Full-Duplex MIMO Systems for Simultaneous Communications and Sensing: Challenges, Methods, and Future Perspectives,” IEEE Signal Process. Mag. , vol. 41, no. 5, Sep. 2024
2024
-
[19]
Integrated Sensing and Communications for 3D Object Imaging via Bilinear Inference,
H. S. Rou, G. T. F. de Abreu, D. Gonz ´alez G., and O. Gonsa, “Integrated Sensing and Communications for 3D Object Imaging via Bilinear Inference,” IEEE Trans. Wireless Commun. , vol. 23, no. 8, 2024
2024
-
[20]
On the Effec- tiveness of OTFS for Joint Radar Parameter Estimation and Communi- cation,
L. Gaudio, M. Kobayashi, G. Caire, and G. Colavolpe, “On the Effec- tiveness of OTFS for Joint Radar Parameter Estimation and Communi- cation,” IEEE Trans. Wireless Commun. , vol. 19, no. 9, 2020
2020
-
[21]
OTFS—A Mathematical Foundation for Communication and Radar Sensing in the Delay-Doppler Domain,
S. K. Mohammed, R. Hadani, A. Chockalingam, and R. Calderbank, “OTFS—A Mathematical Foundation for Communication and Radar Sensing in the Delay-Doppler Domain,” IEEE Inf. Theory Mag. , vol. 2, no. 2, 2022
2022
-
[22]
An Affine Precoded Superimposed Pilot based mmWave MIMO-OFDM ISAC System,
A. Gupta, M. Jafri, S. Srivastava, A. K. Jagannatham, and L. Hanzo, “An Affine Precoded Superimposed Pilot based mmWave MIMO-OFDM ISAC System,” IEEE Open J. Commun. Soc. , vol. 5, 2024
2024
-
[23]
Fast and Efficient Sequential Radar Parameter Estimation in MIMO-OTFS Systems,
K. R. R. Ranasinghe, H. S. Rou, and G. T. F. de Abreu, “Fast and Efficient Sequential Radar Parameter Estimation in MIMO-OTFS Systems,” in Proc. IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) , Seoul, South Korea, 2024
2024
-
[24]
Joint Channel, Data and Radar Parameter Estimation for AFDM Systems in Doubly-Dispersive Channels,
K. R. R. Ranasinghe, H. S. Rou, G. T. F. De Abreu, T. Takahashi, and K. Ito, “Joint Channel, Data and Radar Parameter Estimation for AFDM Systems in Doubly-Dispersive Channels,” IEEE Trans. Wireless Commun., early access, 2024
2024
-
[25]
Integrated Sensing and Communications with Affine Frequency Division Multiplexing,
A. Bemani, N. Ksairi, and M. Kountouris, “Integrated Sensing and Communications with Affine Frequency Division Multiplexing,” IEEE Wireless Commun. Lett. , vol. 13, no. 5, May 2024, 2024
2024
-
[26]
Bilinear Generalized Ap- proximate Message Passing—Part I: Derivation,
J. T. Parker, P. Schniter, and V . Cevher, “Bilinear Generalized Ap- proximate Message Passing—Part I: Derivation,” IEEE Trans. Signal Process., vol. 62, no. 22, 2014
2014
-
[27]
Grant-Free Access via Bilinear Inference for Cell-Free MIMO with Low-Coherence Pilots,
H. Iimori, T. Takahashi, K. Ishibashi, G. T. F. de Abreu, and W. Yu, “Grant-Free Access via Bilinear Inference for Cell-Free MIMO with Low-Coherence Pilots,” IEEE Trans. Wireless Commun., vol. 20, no. 11, 2021
2021
-
[28]
Bayesian Receiver Design via Bilinear Inference for Cell- Free Massive MIMO with Low-Resolution ADCs,
T. Takahashi, H. Iimori, K. Ando, K. Ishibashi, S. Ibi, and G. T. F. de Abreu, “Bayesian Receiver Design via Bilinear Inference for Cell- Free Massive MIMO with Low-Resolution ADCs,”IEEE Trans. Wireless Commun., vol. 22, no. 7, 2023
2023
-
[29]
Blind Detection for Primary User based on the Sample Covariance Matrix in Cognitive Radio,
X. Yang, K. Lei, S. Peng, and X. Cao, “Blind Detection for Primary User based on the Sample Covariance Matrix in Cognitive Radio,” IEEE Commun. Lett. , vol. 15, no. 1, 2011
2011
-
[30]
Improved Blind Spectrum Sensing by Covariance Matrix Cholesky Decomposition and RBF-SVM Decision Classification at Low SNRs,
J. Bao, J. Nie, C. Liu, B. Jiang, F. Zhu, and J. He, “Improved Blind Spectrum Sensing by Covariance Matrix Cholesky Decomposition and RBF-SVM Decision Classification at Low SNRs,” IEEE Access , vol. 7, 2019
2019
-
[31]
Blind Bistatic Radar Parameter Estimation in Doubly- Dispersive Channels,
K. R. R. Ranasinghe, K. Ando, H. S. Rou, G. T. F. de Abreu, and A. Bathelt, “Blind Bistatic Radar Parameter Estimation in Doubly- Dispersive Channels,” to appear in Proc. IEEE Wireless Communications and Networking Conference (WCNC) , Milan, Italy, 2024
2024
-
[32]
An AFDM-based Integrated Sensing and Communications,
Y . Ni, Z. Wang, P. Yuan, and Q. Huang, “An AFDM-based Integrated Sensing and Communications,” in Proc. International Symposium on Wireless Communication Systems , Hangzhou, China, 2022
2022
-
[33]
Affine Frequency Division Multiplexing for Next Generation Wireless Communications,
A. Bemani, N. Ksairi, and M. Kountouris, “Affine Frequency Division Multiplexing for Next Generation Wireless Communications,” IEEE Trans. Wireless Commun. , vol. 22, no. 11, 2023
2023
-
[34]
AFDM Chirp-Permutation-Index Modulation with Quantum-Accelerated Codebook Design,
H. S. Rou, K. Yukiyoshi, T. Mikuriya, G. T. F. de Abreu, and N. Ishikawa, “AFDM Chirp-Permutation-Index Modulation with Quantum-Accelerated Codebook Design,” to appear in Proc. IEEE 57th Asilomar Conference on Signals, Systems, and Computers (Asilomar CSSC), Pacific Grove, CA,...
2024
-
[35]
Joint MIMO Communications and Sensing with Hybrid Beamforming Architecture and OFDM Waveform Optimization,
S. D. Liyanaarachchi, T. Riihonen, C. B. Barneto, and M. Valkama, “Joint MIMO Communications and Sensing with Hybrid Beamforming Architecture and OFDM Waveform Optimization,”IEEE Trans. Wireless Commun., vol. 23, no. 2, 2024
2024
-
[36]
OTFS vs. OFDM in the Pres- ence of Sparsity: A Fair Comparison,
L. Gaudio, G. Colavolpe, and G. Caire, “OTFS vs. OFDM in the Pres- ence of Sparsity: A Fair Comparison,” IEEE Trans. Wireless Commun. , vol. 21, no. 6, 2022
2022
-
[37]
5GHz Chirp Signal Generator for Broadband FMCW Radar Applications,
S. Srivastava and P. Hobden, “5GHz Chirp Signal Generator for Broadband FMCW Radar Applications,” in Proc. IEEE International Symposium on Smart Electronic Systems (iSES) , 2018
2018
-
[38]
Orthogonal Chirp Division Multiplexing,
X. Ouyang and J. Zhao, “Orthogonal Chirp Division Multiplexing,” IEEE Trans. Commun. , vol. 64, no. 9, 2016
2016
-
[39]
Orthogonal Delay-Doppler Division Multiplexing (ODDM) over General Physical Channels,
J. Tong, J. Yuan, H. Lin, and J. Xi, “Orthogonal Delay-Doppler Division Multiplexing (ODDM) over General Physical Channels,” IEEE Trans. Commun., vol. 72, no. 12, 2024
2024
-
[40]
A Tutorial on Extremely Large-Scale MIMO for 6G: Fundamentals, Signal Processing, and Applications,
Z. Wang et al. , “A Tutorial on Extremely Large-Scale MIMO for 6G: Fundamentals, Signal Processing, and Applications,” IEEE Commun. Surveys Tuts., vol. 26, no. 3, 2024
2024
-
[41]
Near-Field Beam Track- ing with Extremely Massive Dynamic Metasurface Antennas,
P. Gavriilidis and G. C. Alexandropoulos, “Near-Field Beam Track- ing with Extremely Massive Dynamic Metasurface Antennas,” arXiv preprint arXiv:2406.01488, 2024
2024 arXiv
-
[42]
Reconfigurable Intelligent Surfaces for Wireless Communica- tions: Overview of Hardware Designs, Channel Models, and Estimation Techniques,
M. Jian, G. C. Alexandropoulos, E. Basar, C. Huang, R. Liu, Y . Liu, and C. Yuen, “Reconfigurable Intelligent Surfaces for Wireless Communica- tions: Overview of Hardware Designs, Channel Models, and Estimation Techniques,” Intell. Converged Netw. , vol. 3, no. 1, 2022
2022
-
[43]
Reconfigurable Intelligent Surfaces for 6G: Emerging Hardware Architectures, Applications, and Open Challenges,
E. Basar, G. C. Alexandropoulos, Y . Liu, Q. Wu, S. Jin, C. Yuen, O. A. Dobre, and R. Schober, “Reconfigurable Intelligent Surfaces for 6G: Emerging Hardware Architectures, Applications, and Open Challenges,” IEEE V eh. Technol. Mag., vol. 19, no. 3, 2024
2024
-
[44]
Reconfigurable Intelligent Surfaces: Principles and Opportu- nities,
Y . Liu, X. Liu, X. Mu, T. Hou, J. Xu, M. Di Renzo, and N. Al- Dhahir, “Reconfigurable Intelligent Surfaces: Principles and Opportu- nities,” IEEE Commun. Surveys Tuts. , vol. 23, no. 3, 2021
2021
-
[45]
Cascaded Metasurfaces for Complete Phase and Polarization Control,
C. Pfeiffer and A. Grbic, “Cascaded Metasurfaces for Complete Phase and Polarization Control,” Appl. Phys. Lett. , vol. 102, no. 23, 2013
2013
-
[46]
Multilayer Noninteracting Dielectric Metasurfaces for Multiwavelength Metaoptics,
Y . Zhou, I. I. Kravchenko, H. Wang, J. R. Nolen, G. Gu, and J. Valentine, “Multilayer Noninteracting Dielectric Metasurfaces for Multiwavelength Metaoptics,” Nano. Lett. , vol. 18, no. 12, 2018
2018
-
[47]
3D-Integrated Metasurfaces for Full-Colour Holography,
Y . Hu, X. Luo, Y . Chen, Q. Liu, X. Li, Y . Wang, N. Liu, and H. Duan, “3D-Integrated Metasurfaces for Full-Colour Holography,” Light Sci. Appl., vol. 8, no. 1, 2019
2019
-
[48]
Channel Estimation for Stacked Intelligent Metasurface-Assisted Wireless Networks,
X. Yao, J. An, L. Gan, M. Di Renzo and C. Yuen, “Channel Estimation for Stacked Intelligent Metasurface-Assisted Wireless Networks,” IEEE Wireless Commun. Lett. , vol. 13, no. 5, May 2024
2024
-
[49]
Stacked Intelligent Metasurfaces for Integrated Sensing and Communications,
H. Niu, J. An, A. Papazafeiropoulos, L. Gan, S. Chatzinotas and M. Debbah, “Stacked Intelligent Metasurfaces for Integrated Sensing and Communications,” IEEE Wireless Commun. Lett. , vol. 13, no. 10, Oct. 2024
2024
-
[50]
Transmit Beamforming Design for ISAC With Stacked Intelligent Metasurfaces,
S. Li, F. Zhang, T. Mao, R. Na, Z. Wang and G. K. Karagiannidis, “Transmit Beamforming Design for ISAC With Stacked Intelligent Metasurfaces,” IEEE Trans. V eh. Technol., vol. 74, no. 4, April 2025
2025
-
[51]
OTFS Transceiver Design and Sparse Doubly-Selective CSI Estimation in Analog and Hybrid Beamforming aided mmWave MIMO Systems,
S. Srivastava, R. K. Singh, A. K. Jagannatham, A. Chockalingam, and L. Hanzo, “OTFS Transceiver Design and Sparse Doubly-Selective CSI Estimation in Analog and Hybrid Beamforming aided mmWave MIMO Systems,” IEEE Trans. Wireless Commun. , vol. 21, no. 12, 2022
2022
-
[52]
Stacked Intelligent Metasurface-aided MIMO Transceiver Design,
J. An, C. Yuen, C. Xu, H. Li, D. W. K. Ng, M. Di Renzo, M. Debbah, and L. Hanzo, “Stacked Intelligent Metasurface-aided MIMO Transceiver Design,” IEEE Wireless Commun. , vol. 31, no. 4, 2024
2024
-
[53]
Two-Dimensional Direction-of-Arrival Estimation using Stacked Intelligent Metasurfaces,
J. An, C. Yuen, Y . L. Guan, M. Di Renzo, M. Debbah, H. V . Poor, and L. Hanzo, “Two-Dimensional Direction-of-Arrival Estimation using Stacked Intelligent Metasurfaces,” IEEE J. Sel. Areas Commun. , vol. 42, no. 10, 2024
2024
-
[54]
Stacked Intelligent Metasurfaces for Efficient Holo- graphic MIMO Communications in 6G,
J. An, C. Xu, D. W. K. Ng, G. C. Alexandropoulos, C. Huang, C. Yuen, and L. Hanzo, “Stacked Intelligent Metasurfaces for Efficient Holo- graphic MIMO Communications in 6G,” IEEE J. Sel. Areas Commun. , vol. 41, no. 8, 2023
2023
-
[55]
Near- Field Full-Duplex Integrated Sensing and Communication with Dynamic Metasurface Antennas,
M. Bayraktar, N. Gonz ´alez-Prelcic, H. Chen and C. J. Zhang, “Near- Field Full-Duplex Integrated Sensing and Communication with Dynamic Metasurface Antennas,” in Proc. IEEE 58th Asilomar Conference on Signals, Systems, and Computers (Asilomar CSSC) , Pacific Grove, CA, USA, 2024
2024
-
[56]
Spatial Modulation and Generalized Spatial Modulation for Dynamic Metasurface Antennas,
A. E. Matemu and K. Lee, “Spatial Modulation and Generalized Spatial Modulation for Dynamic Metasurface Antennas,” IEEE Trans. Wireless Commun., vol. 24, no. 1, Jan. 2025
2025
-
[57]
Dynamic Scattering Arrays for Simultaneous Electromag- netic Processing and Radiation in Holographic MIMO Systems,
D. Dardari, “Dynamic Scattering Arrays for Simultaneous Electromag- netic Processing and Radiation in Holographic MIMO Systems,” arXiv preprint:2405.16174, 2024
2024 arXiv
-
[58]
Uplink Performance of Stacked Intelligent Metasurface-Enhanced Cell-Free Massive MIMO Systems,
E. Shi, J. Zhang, Y . Zhu, J. An, C. Yuen and B. Ai, “Uplink Performance of Stacked Intelligent Metasurface-Enhanced Cell-Free Massive MIMO Systems,” IEEE Trans. Wireless Commun. , 2025
2025
-
[59]
Efficient and Physically Consistent Modeling of Reconfigurable Electromagnetic Structures,
A. Stutz-Tirri, G. Schwan and C. Studer, “Efficient and Physically Consistent Modeling of Reconfigurable Electromagnetic Structures,” IEEE Open J. Commun. Soc. , vol. 6, 2025
2025
-
[60]
Stacked Intelligent Metasurfaces for Multiuser Downlink Beamforming in the Wave Domain,
J. An, M. D. Renzo, M. Debbah, H. V . Poor and C. Yuen, “Stacked Intelligent Metasurfaces for Multiuser Downlink Beamforming in the Wave Domain,” IEEE Trans. Wireless Commun. , 2025
2025
-
[61]
Beyond Diagonal Re- configurable Intelligent Surfaces utilizing Graph Theory: Modeling, Architecture Design, and Optimization,
M. Nerini, S. Shen, H. Li, and B. Clerckx, “Beyond Diagonal Re- configurable Intelligent Surfaces utilizing Graph Theory: Modeling, Architecture Design, and Optimization,” IEEE Trans. Wireless Commun., vol. 23, no. 8, 2024
2024
-
[62]
Physically-Consistent Modeling and Optimization of non-local RIS-Assisted Multi-User MIMO Communication Systems,
D. Wijekoon, A. Mezghani, G. C. Alexandropoulos, and E. Hos- sain, “Physically-Consistent Modeling and Optimization of non-local RIS-Assisted Multi-User MIMO Communication Systems,” arXiv preprint:2406.05617, 2024
2024 arXiv
-
[63]
Orthogonal Time Frequency Space Mod- ulation,
R. Hadani, S. Rakib, M. Tsatsanis, A. Monk, A. J. Goldsmith, A. F. Molisch, and R. Calderbank, “Orthogonal Time Frequency Space Mod- ulation,” in Proc. IEEE Wireless Communications and Networking Conference (WCNC), San Francisco, USA, 2017
2017
-
[64]
Interference Can- cellation and Iterative Detection for Orthogonal Time Frequency Space Modulation,
P. Raviteja, K. T. Phan, Y . Hong, and E. Viterbo, “Interference Can- cellation and Iterative Detection for Orthogonal Time Frequency Space Modulation,” IEEE Trans. Wireless Commun. , vol. 17, no. 10, 2018
2018
-
[65]
A Low-Complexity Radar System based on Affine Frequency Division Multiplexing Modulation,
J. Zhu, Y . Tang, X. Wei, H. Yin, J. Du, Z. Wang, and Y . Liu, “A Low-Complexity Radar System based on Affine Frequency Division Multiplexing Modulation,” arXiv preprint arXiv:2312.11125 , 2023
2023 arXiv
-
[66]
Pre-Chirp-Domain Index Modulation for Affine Frequency Division Multiplexing,
G. Liu, T. Mao, R. Liu, and Z. Xiao, “Pre-Chirp-Domain Index Modulation for Affine Frequency Division Multiplexing,” arXiv preprint arXiv:2402.15185, 2024
2024 arXiv
-
[67]
Diversity-Multiplexing Tradeoff in Multiple-Access Channels,
D. Tse, P. Viswanath, and L. Zheng, “Diversity-Multiplexing Tradeoff in Multiple-Access Channels,” IEEE Trans. Inf. Theory , vol. 50, no. 9, 2004
2004
-
[68]
Hybrid Beamforming for Massive MIMO: A Survey,
A. F. Molisch, V . V . Ratnam, S. Han, Z. Li, S. L. H. Nguyen, L. Li, and K. Haneda, “Hybrid Beamforming for Massive MIMO: A Survey,” IEEE Commun. Mag. , vol. 55, no. 9, 2017
2017
-
[69]
Sum-Rate Maximization and Leakage Minimization for Multi-User Cell-Free Massive MIMO Systems,
I. A. M. Sandoval, K. Ando, O. Taghizadeh, and G. T. F. De Abreu, “Sum-Rate Maximization and Leakage Minimization for Multi-User Cell-Free Massive MIMO Systems,” IEEE Access , vol. 11, 2023
2023
-
[70]
Stacked Intelligent Metasurface performs a 2D DFT in the Wave Domain for DOA Estimation,
J. An, C. Yuen, Y . L. Guan, M. Di Renzo, M. Debbah, H. V . Poor, and L. Hanzo, “Stacked Intelligent Metasurface performs a 2D DFT in the Wave Domain for DOA Estimation,” in Proc. IEEE International Conference on Communications (ICC) , Denver, CO, USA, 2024
2024
-
[71]
oint Activity and Channel Estimation for Extra-Large MIMO Systems,
H. Iimori, T. Takahashi, K. Ishibashi, G. T. F. de Abreu, D. Gonz ´alez G. and O. Gonsa, “oint Activity and Channel Estimation for Extra-Large MIMO Systems,” IEEE Trans. Wireless Commun. , vol. 21, no. 9, 2022
2022
-
[72]
Joint Channel and Data Estimation via Parametric Bilinear Inference for OTFS Demodulation,
K. Ito, T. Takahashi, K. Furuta, S. Ibi and G. Thadeu Freitas de Abreu, “Joint Channel and Data Estimation via Parametric Bilinear Inference for OTFS Demodulation,” IEEE Open J. Commun. Soc. , vol. 5, 2024
2024
-
[73]
Bayesian Bilinear Inference for Joint Channel Tracking and Data Detection in Millimeter-Wave MIMO Systems,
T. Takahashi, H. Iimori, K. Ishibashi, S. Ibi and G. T. F. de Abreu, “Bayesian Bilinear Inference for Joint Channel Tracking and Data Detection in Millimeter-Wave MIMO Systems,” IEEE Trans. Wireless Commun., vol. 23, no. 9, 2024
2024
-
[74]
Design of Adaptively Scaled Belief in Multi-Dimensional Signal Detection for Higher-Order Modulation,
T. Takahashi, S. Ibi, and S. Sampei, “Design of Adaptively Scaled Belief in Multi-Dimensional Signal Detection for Higher-Order Modulation,” IEEE Trans. Commun. , vol. 67, no. 3, 2019
2019
-
[75]
On Convergence Conditions of Gaussian Belief Propagation,
Q. Su and Y .-C. Wu, “On Convergence Conditions of Gaussian Belief Propagation,” IEEE Trans. Signal Process. , vol. 63, no. 5, 2015
2015
-
[76]
Parametrized Stacked Intelligent Metasurfaces for Bistatic Integrated Sensing and Communications,
K. R. R. Ranasinghe, I. A. M. Sandoval, G. T. F. de Abreu and G. C. Alexandropoulos, “Parametrized Stacked Intelligent Metasurfaces for Bistatic Integrated Sensing and Communications,” arXiv preprint arXiv:2504.20661, 2025
2025 arXiv
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