Enhancing Spectral Access through Adaptive Terahertz Communication Systems

通过自适应太赫兹通信系统增强频谱访问

• 批准号: 1608980
• 负责人: Mona Jarrahi
• 金额: $ 40万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-15 至 2020-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1608980&HistoricalAwards=false
• 关键词: Enhancing; Spectral; Access; through; Adaptive

High-speed wireless communication has attracted extensive attention in the past decades because of dramatic changes in the ways people create and share information. The expected data rate to satisfy the needs of the customers is projected to be 100 Gbit/s by 2020. However, the speed of today's wireless communication systems is limited by the narrow bandwidth of existing transmitters and receivers and the heavy use of the electromagnetic spectrum up to 60 GHz. This trend has been forcing researchers to push the carrier frequencies of transceivers to higher frequencies to allow operation at frequency bands which have not been allocated to any specific active service yet. In order to increase the channel capacity, researchers have been trying to operate at terahertz frequencies, which cover the frequency range of 0.3-10 THz in the electromagnetic spectrum. While communication systems with such high carrier frequencies have been hard to develop so far, a data link operating at terahertz frequencies with data rates exceeding 100 Gbit/s over 10-20 meters distance is believed to be viable now thanks to recent advancements in terahertz photonics and electronics. The research component of this program plans to develop such a high data rate wireless communication system at terahertz carrier frequencies for indoor communication applications. A system with this capability can be very suitable for the next generation indoor wireless communication systems such as wireless local area networks and wireless personal area networks, kiosk downloads, wireless backhauling, data center connection, and real-time data analysis for wearable devices. Additionally, this program plans to integrate research with education and outreach activities by developing new courses, recruitment and involvement of undergraduate students, and organizing high-school seminars. During this program a directional terahertz transceiver system based on an adaptive two-dimensional array of plasmonic photomixers operating under novel communication protocols is designed, fabricated, and experimentally demonstrated. The proposed work presents an entirely new perspective on the potential use of terahertz bandwidth for increasing wireless communication data rates to levels that could not be envisioned before due to low output power and limited adaptability of existing terahertz transmitters. This limitation can be tackled through use of plasmonic photomixer arrays that offer significantly higher terahertz radiation powers and higher level of transmitter adaptability compared to other terahertz transmitter candidates. Additionally, the adaptive nature of the proposed terahertz transceiver system allows compensation for accidental misalignments and shadowing effects through beam-forming and non-line-of-sight communication links. While theoretical investigations provide a deep understanding of fundamental physical limitations of terahertz transceiver systems based on plasmonic photomixer arrays and achievable wireless communication data rates, the experimental effort provides valuable data to develop accurate channel models at terahertz frequencies in order to utilize appropriate communication modalities, equalization techniques, and adaptive signal tracking systems to mitigate signal fading in indoor terahertz communication systems.

由于人们创建和共享信息的方式发生了巨大变化，高速无线通信在过去几十年中引起了广泛关注。到 2020 年，满足客户需求的预期数据速率预计将达到 100 Gbit/s。然而，当今无线通信系统的速度受到现有发射器和接收器的窄带宽以及电磁频谱的大量使用的限制高达 60 GHz。这一趋势迫使研究人员将收发器的载波频率推向更高的频率，以允许在尚未分配给任何特定活动服务的频段上运行。为了增加通道容量，研究人员一直在尝试在太赫兹频率下工作，该频率覆盖电磁频谱中0.3-10 THz的频率范围。虽然到目前为止，具有如此高载波频率的通信系统很难开发，但由于太赫兹光子学的最新进展，在太赫兹频率下运行、在 10-20 米距离内数据速率超过 100 Gbit/s 的数据链路现在被认为是可行的和电子产品。该计划的研究部分计划开发用于室内通信应用的太赫兹载波频率的高数据速率无线通信系统。具有这种能力的系统非常适合下一代室内无线通信系统，例如无线局域网和无线个域网、信息亭下载、无线回程、数据中心连接以及可穿戴设备的实时数据分析。此外，该项目计划通过开发新课程、招募和参与本科生以及组织高中研讨会，将研究与教育和推广活动结合起来。在该项目中，设计、制造并通过实验演示了基于在新型通信协议下运行的自适应二维等离子体光混频器阵列的定向太赫兹收发器系统。由于现有太赫兹发射机的低输出功率和有限的适应性，拟议的工作为太赫兹带宽的潜在用途提供了一个全新的视角，以将无线通信数据速率提高到以前无法想象的水平。这一限制可以通过使用等离子体光混合器阵列来解决，与其他候选太赫兹发射器相比，该阵列可提供明显更高的太赫兹辐射功率和更高水平的发射器适应性。此外，所提出的太赫兹收发器系统的自适应特性允许通过波束形成和非视距通信链路补偿意外的未对准和阴影效应。虽然理论研究深入了解了基于等离子体光混频器阵列和可实现的无线通信数据速率的太赫兹收发器系统的基本物理限制，但实验工作提供了宝贵的数据来开发太赫兹频率下的准确信道模型，以便利用适当的通信方式、均衡技术和自适应信号跟踪系统，以减轻室内太赫兹通信系统中的信号衰落。