Fiber-Wireless-Fiber Fully Integrated D-Band System (FiWiFi)

目前的光电无线桥由混合系统组成，其中光学和电子部件是不同的mmic，通过微线或倒装芯片键合封装，并通过放置天线的母板相互通信。这主要反映在损耗和带宽减少上，限制了无线链路速度方面的性能。该提案旨在通过将从光纤到天线的整个链完全集成到单个芯片上来克服这些实际问题。特别是，该项目旨在通过IHP开发一个新的技术平台，允许集成高速光学元件，如光电二极管和马赫-曾德调制器，高射频电路，如混频器和放大器，以及片上基于lbe的天线。该方案旨在结合硅体的局部背面蚀刻，开发在硅体顶部构造金属层的新技术特征。考虑到数据中心光纤内的典型数据速率、技术频率限制和天线尺寸，选择了d波段。从一端到170千兆赫之间的宽频带允许非常高的数据速率，但从另一端推到电子电路，光学元件和天线的设计极限。•光电发射器和接收器的速度：当前版本的光电接收器和发射器的速度还不足以支持所需的带宽。更快的tia和MZM的驱动程序将被设计出来。收发器和天线带宽：以140 GHz为中心的60 GHz带宽导致43%的相对带宽。最重要的是，d波段非常接近技术频率限制。•通信距离：目标应用程序需要几米的无线连接。考虑到所选频段的高自由空间路径损耗，有限的可实现输出功率和噪声系数以及片上天线的低典型增益，这样的距离变得非常具有挑战性。申请人通过提出一种完全集成的双芯片方法来解决上述所有挑战，其中Tx和Rx芯片无线通信。该系统的主要优点是完全集成，从光纤到天线在Tx侧，反之亦然。在自互补多模天线的帮助下，利用局部背面蚀刻和硅体上结构金属层相结合的新技术特点，在不同的辐射方向上获得足够的天线增益，同时实现大带宽。

Current opto-electronic wireless bridges consist of hybrid systems where optical and electronic parts are different MMICs packaged through micro-wires or flip-chip bonding and communicating each other through a mother board where the antenna finds place. This reflects mostly into losses and bandwidth reduction, limiting the performance in terms of wireless link speed. This proposal aims to overcome those practical problems through a full integration onto a single chip of the entire chain, from the fiber to the antenna. In particular, the project aims at exploiting a new technology platform by IHP allowing the integration of high-speed optical components as photodiodes and Mach-Zehnder modulators, high rf-circuits as mixers and amplifiers and on-chip LBE-based antennas. The proposal aims at exploiting the new technological feature of structuring the metallic layer on top of the silicon bulk in combination with localized backside etching of the bulk.Considering the typical data-rate within fibers in a data center the technological frequency limits and the antenna size, the D-Band has been selected. The wide frequency band between 110 and 170 GHz from one side allows very high data-rates, but from the other pushes to the limit the design of electronic circuits, optical components and antennas. The following main objectives are addressed:• Opto-electronic transmitter and receiver speed: the speed of the current versions of both opto-electronic receiver and transmitter is not yet enough to support the desired bandwidth. Faster TIAs and MZM’s drivers will be designed.• Transceiver and antenna bandwidth: The 60 GHz bandwidth centered at 140 GHz results in 43% relative bandwidth. On top of that, the D-Band is very close to the technological frequency limits. • Communication distance: The targeted application requires a wireless link up to some meters. Given the high free space path loss at the selected frequency band, the limited achievable output power and noise figure and the low typical gain of on-chip antennas, such a distance turns to be very challenging. The applicants address all the mentioned challenges by proposing a fully integrated two-chip approach, where a Tx and a Rx chip communicate wirelessly. The main strength of this system is the full integration, from the fiber to the antenna on the Tx side and vice versa. With the help of self-complimentary multimode antennas, sufficient antenna gains at simultaneously large bandwidth in various directions of radiation are aimed at, realized by antennas exploiting the new technological feature of the combination of localized backside etching and a structured metallic layer on top of the silicon bulk.