{"ID":2868575,"CreatedAt":"2026-06-01T04:54:23.091178241Z","UpdatedAt":"2026-06-01T04:54:23.091178241Z","DeletedAt":null,"paper_url":"https://arxiv.org/abs/2509.15564","arxiv_id":"2509.15564","title":"CSIT-Free Downlink Transmission for mmWave MU-MISO Systems in High-Mobility Scenario","abstract":"This paper investigates the downlink (DL) transmission in millimeter-wave (mmWave) multi-user multiple-input single-output (MU-MISO) systems especially focusing on a high speed mobile scenario. To complete the DL transmission within an extremely short channel coherence time, we propose a novel DL transmission framework that eliminates the need for channel state information at the transmitter (CSIT), of which acquisition process requires a substantial overhead, instead fully exploiting the given channel coherence time. Harnessing the characteristic of mmWave channel and uniquely designed CSIT-free unitary precoding, we propose a symbol detection method along with the simultaneous CSI at the receiver (CSIR) and Doppler shift estimation method to completely cancel the interferences while achieving a full combining gain. Via simulations, we demonstrate the effectiveness of the proposed method comparing with the existing baselines.","short_abstract":"This paper investigates the downlink (DL) transmission in millimeter-wave (mmWave) multi-user multiple-input single-output (MU-MISO) systems especially focusing on a high speed mobile scenario. To complete the DL transmission within an extremely short channel coherence time, we propose a novel DL transmission framework...","url_abs":"https://arxiv.org/abs/2509.15564","url_pdf":"https://arxiv.org/pdf/2509.15564v1","authors":"[\"Jeongjae Lee\",\"Wonseok Choi\",\"Songnam Hong\"]","published":"2025-09-19T03:57:58Z","proceeding":"eess.SP","tasks":"[\"eess.SP\"]","methods":"[]","has_code":false}