OrpQuant解决了低比特量化中特征流形退化的问题，做边缘部署的开发者可以直接用这个15分钟校准的方案替代传统MAC密集型方法，硬件效率显著提升。
OrpQuant提出了一种名为正交残差投影（ORP）的算法-硬件协同设计框架，用于解决低比特Power-of-Two（PoT）量化中的低角度分辨率问题。该方法通过双基几何投影自适应合成更高分辨率的残差格点，仅使用移位和加法操作，避免了乘法器。在LLaMA-2-7B上，3比特量化（W3/A16）下困惑度达到6.10，与AWQ等MAC密集型方法相当，且全模型校准仅需约15分钟。在28nm工艺下，RTL综合表明ORP有效缓解了密集乘法器树的时序瓶颈。该工作适用于LLM和ViT的边缘部署。
OrpQuant: Geometric Orthogonal Residual Projection for Multiplier-Free Power-of-Two Transformer Quantization
The deployment of Large Language Models (LLMs) and Vision Transformers (ViTs) on edge devices is significantly constrained by memory limitations and the critical timing bottlenecks introduced by dense Multiply-Accumulate (MAC) arrays. In the ultra-low bit regime, logarithmic Power-of-Two (PoT) quantization provides a hardware-efficient alternative by replacing MAC operations with bit-shifts. However, the non-uniform exponential lattice is inherently limited by a \textbf{Low Angular Resolution Regime}, a structural flaw that becomes particularly pronounced at sub-4-bit thresholds, leading to a notable degradation of high-dimensional feature manifolds. To address this geometric limitation, we propose Orthogonal Residual Projection (ORP), an algorithm-hardware co-design framework. By formulating quantization as a dual-basis geometric projection, ORP adaptively synthesizes a higher-resolution residual lattice using strictly shift-and-add operations. Furthermore, ORP's analytical solver offers a practical alternative to computationally intensive gradient-based optimization, reducing the full-model calibration time for LLaMA-2-7B to approximately \textbf{15 minutes}. Extensive evaluations demonstrate ORP's applicability across modalities and its hardware efficiency. Under the 3-bit (W3/A16) constraint, ORP achieves a perplexity of 6.10 on LLaMA-2-7B, comparing favorably to conventional MAC-intensive baselines like AWQ without relying on asymmetric scaling, while maintaining competitive accuracy in 4-bit scenarios. At the silicon level, standard-cell RTL synthesis at a 28nm node indicates that ORP effectively mitigates the timing bottlenecks associated with dense multiplier trees.