# CUHKSZ Simultaneous Speech Translation System for IWSLT 2026

> Source: <https://aclanthology.org/2026.iwslt-1.13/>
> Published: 2026-06-30 00:00:00+00:00

##### Abstract

We present the CUHKSZ Team submission to the IWSLT 2026 Simultaneous Speech Translation evaluation, targeting the main and Extra Context tracks for English→Chinese, German on unsegmented speech. Our system is built upon Qwen3-Omni-30B-A3B, a natively aligned audio-text LLM. Under the Constrained condition, we apply LoRA adaptation exclusively to the LLM. Specifically, we construct syntax-aware, chunk-aligned supervision from existing ASR corpora, using Qwen3-30B-Instruct to synthesize target translations. This enables the model to internalize the simultaneous read/write policy by autonomously predicting <wait> tokens at semantically incomplete boundaries. With the policy internalized, execution is delegated to a lightweight streaming agent served via vLLM. This agent feeds audio in fixed chunks, manages a bounded dialogue history, and enforces strict emission controls to minimize computation-aware delay. For the sub-track, contextual priors are dynamically injected into the prompt. On the official dev set, our 0–2 s latency regime submissions achieve 40.5 BLEU (1.95 s) for En→Zh and 27.7 BLEU (1.72 s) for En→De. In the 2–4 s regime, performance scales to 42.1 BLEU (2.16 s) and 30.5 BLEU (2.29 s) respectively.- Anthology ID:
- 2026.iwslt-1.13
- Volume:
[Proceedings of the 23rd International Conference on Spoken Language Translation (IWSLT 2026)](/volumes/2026.iwslt-1/)- Month:
- July
- Year:
- 2026
- Address:
- San Diego, USA (in-person and online)
- Editors:
[Elizabeth Salesky](/people/elizabeth-salesky/),[Antonios Anastasopoulos](/people/antonios-anastasopoulos/),[Matteo Negri](/people/matteo-negri/),[Marcello Federico](/people/marcello-federico/)- Venues:
[IWSLT](/venues/iwslt/)|[WS](/venues/ws/)- SIG:
[SIGSLT](/sigs/sigslt/)- Publisher:
- Association for Computational Linguistics
- Note:
- Pages:
- 111–118
- Language:
- URL:
[https://aclanthology.org/2026.iwslt-1.13/](https://aclanthology.org/2026.iwslt-1.13/)- DOI:
- Cite (ACL):
- Zeyu Yang and Satoshi Nakamura. 2026.
[CUHKSZ Simultaneous Speech Translation System for IWSLT 2026](https://aclanthology.org/2026.iwslt-1.13/). In*Proceedings of the 23rd International Conference on Spoken Language Translation (IWSLT 2026)*, pages 111–118, San Diego, USA (in-person and online). Association for Computational Linguistics. - Cite (Informal):
[CUHKSZ Simultaneous Speech Translation System for IWSLT 2026](https://aclanthology.org/2026.iwslt-1.13/)(Yang & Nakamura, IWSLT 2026)- PDF:
[https://aclanthology.org/2026.iwslt-1.13.pdf](https://aclanthology.org/2026.iwslt-1.13.pdf)