Masked diffusion models (MDMs) offer a promising non-autoregressive alternative for large language modeling.Standard decoding methods for MDMs, such as confidence-based sampling, select tokens independently based on individual token confidences at each diffusion step.However, we observe that this independent token selection often results in generation orders resembling sequential autoregressive processes, limiting the advantages of non-autoregressive modeling.To mitigate this pheonomenon, we propose Reward-Weighted Sampling (RWS), a novel decoding strategy that leverages an external reward model to provide a principled global signal during the iterative diffusion process.Specifically, at each diffusion step, RWS evaluates the quality of the entire intermediate sequence and scales token logits accordingly, guiding token selection by integrating global sequence-level coherence.This method selectively increases the confidence of tokens that initially have lower scores, thereby promoting a more non-autoregressive generation order.Furthermore, we provide theoretical justification showing that rewardweighted logit scaling induces beneficial rank reversals in token selection and consistently improves expected reward.Experiments demonstrate that RWS significantly promotes nonautoregressive generation orders, leading to improvements across multiple evaluation metrics.These results highlight the effectiveness of integrating global signals in enhancing both the non-autoregressive properties and overall performance of MDMs.

Compared to conventional 3D radar, the 4D imaging radar provides additional height data and finer resolution measurements. Moreover, compared to LiDAR sensors, 4D imaging radar is more cost-effective and offers enhanced durability against challenging weather conditions. Despite these advantages, radar-based localization systems face several challenges, including limited resolution, leading to scattered object recognition and less precise localization. Additionally, existing methods that form submaps from filtered results can accumulate errors, leading to blurred submaps and reducing the accuracy of the SLAM and odometry. To address these challenges, this paper introduces Radar4VoxMap, a novel approach designed to enhance radar-only odometry. The method includes an RCS-weighted voxel distribution map that improves registration accuracy. Furthermore, fixed-lag optimization with the graph is used to optimize both the submap and pose, effectively reducing cumulative errors. The proposed method has shown strong performance on open datasets. The code is available at: https://github.com/ailab-hanyang/Radar4VoxMap