权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Millimetre wave double corrugated waveguide TWT

毫米波双波纹波导TWT

基本信息

批准号：
ST/L003406/1
负责人：
Claudio Paoloni
金额：
$ 10.14万
依托单位：
Lancaster University
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2014
资助国家：
英国
起止时间：
2014 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=ST%2FL003406%2F1
关键词：
Millimetre wave double corrugated waveguide

项目摘要

Traveling wave tubes (TWTs) are among the oldest electronic amplifiers, invented in 1943, but they remain the only devices able to provide high power in a wide frequency band at microwave & millimetre wave frequencies. Without TWTs, no satellite communications, high-speed wireless communications, radars and many other fundamental applications would be possible. A TWT consists of a filament wound in helical shape where an electron beam is generated. The helix is supported by longitudinal dielectric rods that are placed concentric to a metal vacuum envelope. The electromagnetic wave is slowed at about the same velocity as the electrons, causing bunching of the electrons. In turn, the electromagnetic field retards the bunches and their kinetic energy is transferred to the oscillating field, thereby amplifying it. Current fabrication technology permits the realisation of helices with diameters below 1mm that support frequencies up to around 60 GHz in principle. To assemble a helix with these dimensions requires a highly skilled operator and takes a long time. Further, the uncertainty in the fabrication of the small parts causes a low yield. The cost of such a millimetre wave tube is very high, >£10k, limiting its use to some specific applications. On the contrary the demand for high power millimetre waves amplifiers is growing. One application, wireless gigabit data communications is a global business that requires wide band, high power, amplification at frequency above 50 GHz to support multigigabit free space transmission. An improved TWT addresses this market need directly. This project aims to overcome the frequency limitation of the helix TWT by introducing a novel double corrugated waveguide (DCW), in place of the helix. The DCW was conceived by the PI to permit the design and fabrication of the first 1 THz, 1000 GHz, TWT amplifier. The behaviour of the DCW at lower frequency as a slow wave structure with similar performance to a helix, but much easier to manufacture, will be investigated. Precision CNC milling, with micrometer accuracy, will be used to define the DCW.The great advantage of the DCW over the helix is the ease of assembly: the DCW is a metal structure made from two parts that can be aligned by features and then simply clamped together. One part is a hollow rectangular metal waveguide with two parallel rows of metal pillars along the guide: the other part is a top plate to close and complete the waveguide. No precision alignment is required and the assembly time is minimal: the skill of the assembler having been replaced by the precision of the machining. The introduction of the DCW in TWTs will substantially reduce the fabrication cost and overcome the frequency limitation of the helices. The innovation that the double corrugated waveguide will bring is of great importance and will foster the development of a new family of low cost, high performance vacuum electron devices, that will give the UK outstanding market perspective and employment opportunities. Lancaster University has a strong international reputation in the field and will design the novel TWT, also investigating the range of frequencies that can be amplified by devices based on the new DWP structure. e2v, the main UK vacuum electronics company will support the design process with its fabrication experience and facilities. e2v will also characterise electromagnetically the completed devices. The designs of double corrugated waveguide will be realised by state-of-the-art microfabrication facilities in the Millimetre Wave Technology Group, part of the RAL Space department at the STFC Rutherford Appleton Laboratory. At the end of the project an optimised design of the first double corrugated waveguide TWT for millimetre wave frequency range will be realised for experimental verification at e2v. This successful realisation will be the prototype demonstrator for the following production engineering for eventual commercial supply.

行波管 (TWT) 是最古老的电子放大器之一，发明于 1943 年，但它们仍然是唯一能够在微波和毫米波频率的宽频带内提供高功率的设备。如果没有行波管，卫星通信、高速无线通信、雷达和许多其他基本应用就不可能实现。 TWT 由缠绕成螺旋形状的灯丝组成，在灯丝中产生电子束。螺旋由与金属真空外壳同心放置的纵向介电棒支撑。电磁波以与电子大致相同的速度减慢，导致电子聚集。反过来，电磁场使束团减速，它们的动能被转移到振荡场，从而放大它。目前的制造技术允许实现直径低于 1mm 的螺旋，原则上支持高达 60 GHz 左右的频率。要组装具有这些尺寸的螺旋线需要高度熟练的操作员并且需要很长时间。此外，小部件制造的不确定性导致产量低。这种毫米波管的成本非常高，> 10,000 英镑，限制了其在某些特定应用中的使用。相反，对高功率毫米波放大器的需求正在增长。其中一个应用是无线千兆位数据通信，这是一项全球性业务，需要频率高于 50 GHz 的宽带、高功率放大，以支持多千兆位自由空间传输。改进的行波管直接满足了这一市场需求。该项目旨在通过引入新型双波纹波导（DCW）代替螺旋来克服螺旋行波管的频率限制。 DCW 由 PI 构想，旨在允许设计和制造第一个 1 THz、1000 GHz、TWT 放大器。将研究 DCW 在较低频率下的行为，作为慢波结构，其性能与螺旋相似，但更容易制造。具有微米精度的精密 CNC 铣削将用于定义 DCW。DCW 相对于螺旋的巨大优势是易于组装：DCW 是由两个部件制成的金属结构，可以按特征对齐，然后简单地夹紧在一起。一部分是中空的矩形金属波导，沿着波导有两排平行的金属柱：另一部分是顶板，用于封闭和完善波导。无需精确对准，组装时间也很短：组装工的技能已被加工精度所取代。在行波管中引入 DCW 将大大降低制造成本并克服螺旋的频率限制。双波纹波导带来的创新具有重要意义，将促进低成本、高性能真空电子器件新系列的开发，这将为英国带来出色的市场前景和就业机会。兰卡斯特大学在该领域享有很高的国际声誉，将设计新颖的行波管，同时研究基于新的 DWP 结构的设备可以放大的频率范围。英国主要真空电子公司 e2v 将以其制造经验和设施支持设计过程。 e2v 还将对完成的设备进行电磁表征。双波纹波导的设计将通过毫米波技术组最先进的微加工设施来实现，毫米波技术组是 STFC 卢瑟福阿普尔顿实验室 RAL 空间部门的一部分。项目结束后，将实现首个毫米波频率范围双波纹波导行波管的优化设计，并在e2v上进行实验验证。这一成功实现将成为最终商业供应的后续生产工程的原型演示。