26 岁，他刚毕业，便被学校应聘为副教授。只因他在芯片领域中的研究着实太突出：自主研发毫米波通信芯片。他叫张志维，目前就职于杭州电子科技大学。而就是这颗“两三粒芝麻大小”的芯片，却能足以满足 5G 甚至 6G 通信对于传输速率的需求。用张志维自己的话来说就是：功率更高了，传输距离更大了。
以前覆盖面积只有半个足球场那么大，现在最新的实验结果能传 10 公里。
很多网友在祝贺、点赞张志维取得突破成果之余，对张志维 26 岁能当上副教授这事陷入了“深思”：
谢绝 60 万年薪，选择留校任教
张志维本硕博均是就读于在杭州电子科技大学。主要研究方向是微波 / 毫米波，与 5G / 6G 通讯密切相关。
为此，他在 2020 年还特意去国外深造，每天坚持搞研究长达 12 小时。
或许正是张志维如此的努力和拼搏，他在 2020 年到 2021 年期间，在芯片领域拿下了 2 个首次：
首次提出混合 EFJ 功率放大器
今年 3 月份，张志维顺利完成了博士论文的答辩。
而即便众多大厂纷纷向他抛出橄榄枝、提供 60 万年薪的 Offer，但张志维却毅然决然地选择了留校。
发表过 19 篇 SCI 论文
据杭州电子科技大学 2022 年“十佳大学生”评选现场宣传材料，张志维在硕博连读的 5 年时间内，共发表了 19 篇 SCI 论文。
他以第一作者身份发表的 SCI 论文超过 10 篇，其中 9 篇发表于 IEEE 协会旗下期刊。
这些论文里面当然也包括提出混合 EFJ 功率放大器，以及阻抗频率调制的研究成果文章。
2020 年，张志维在导师程知群等人的指导下，研发出一种采用新型混合连续级 EFJ 功率放大器，来放大载波。
此前，Doherty 功率放大器（DPA）由于结构简单、成本低，在被基站中被广泛应用。但是传统的 DPA 有一些固有缺点，例如：带宽狭窄，且只有 6dB 的 output back-off 范围。
而张志维和团队提出的 EFJ 类功率放大器的负载阻抗，不仅有传统的连续功率放大器类似的可变虚部，还有不一致的实部。
所以 EFJ 类功率放大器可有效结合 EF 类功率放大器的高能效，以及连续 J 类功率放大器在特定条件下的大带宽，从而大大弥补了 DPA 的缺陷。
2021 年，张志维和来自英国贝尔法斯特女王大学的 Vincent Fusco 等人在 IEEE Transactions on Circuits and Systems II 上发表了阻抗频率调制的研究成果论文。
通过结合获得的周期性阻抗轨迹和 EFJ 类功率放大器的阻抗空间，实现了实时获取所需的工作频率。
目前，张志维和团队正在研究毫米波通信芯片 3.0 版本的技术迭代。
One More Thing
张志维拒绝 60 万年薪留校任教引发的热议，除了前文提到的内容之外，其实还有另外一种声音。
有人认为大厂给张志维开出 60 万年薪，并不是很高：
之前互联网随随便便一个应届生 40 万 +……
Photo & nbsp; Source: blue News of China
In the past, the coverage area was only half the size of a football field, but now the latest experimental results can travel 10 kilometers.
For ordinary people, the definition of the phone will be better and the Internet speed will be higher.
Photo & nbsp; Source: blue News of China
More importantly, millimeter wave chips have been monopolized by foreign countries for a long time. However, with the successful research and development of Zhang Zhiwei and his team, his mentor thought:
In some areas, we should be able to stop relying on foreign chips and solve the problem of “neck jam”.
It is understood that the chip has been used in mobile base stations to achieve high-speed data transmission between satellite and ground base stations, and between base stations and base stations.
As soon as the news was announced, it immediately aroused the high attention of a large number of netizens:
Even Zhang Zhiwei’s alma mater, Hangzhou University of Electronic Science and Technology, sent a congratulatory message:
While congratulating and praising Zhang Zhiwei for his breakthrough, many netizens fell into “deep thinking” about Zhang Zhiwei becoming an associate professor at the age of 26:
However, in addition to the achievement itself, Zhang Zhiwei’s previous study and research and development experience has also become the focus of this hot discussion.
Declined 600,000 annual salary and chose to stay in school and teach.
Zhang Zhiwei studied at Hangzhou University of Electronic Science and Technology for his master’s degree. The main research direction is microwave / millimeter wave, which is closely related to 5G / 6G communication.
And he decided to develop the chip, but also from an undergraduate experience.
At that time, Zhang Zhiwei was taking part in the competition, but ended in failure. The reason is that the chip used by Zhang Zhiwei malfunctioned during the competition.
As a result, the matter of “core-making” was deeply buried in his heart.
To this end, he went abroad for further study in 2020 and kept on doing research for 12 hours a day.
Perhaps it was Zhang Zhiwei who worked so hard and worked so hard that he won two firsts in the chip field between 2020 and 2021:
A hybrid EFJ power amplifier is proposed for the first time.
The concept of impedance frequency modulation is proposed for the first time.
Even his mentors abroad commented that he had “lived up to your alma mater”.
And these “achievements” also laid a solid foundation for Zhang Zhiwei to build the core later.
In March this year, Zhang Zhiwei successfully completed the defense of his doctoral thesis.
But at that time, he was faced with a choice between the two–
Either go to a big factory or stay in school.
Even though many big companies offered him an Offer with an annual salary of 600,000, Zhang Zhiwei resolutely chose to stay in school.
Photo & nbsp; source: official website of Hangzhou University of Electronic Science and Technology
According to the description of China Science Daily, the reasons why Zhang Zhiwei chose to stay in school and teach are:
Because I like the campus free and full of “creative core” atmosphere.
Such a choice also made Zhang Zhiwei become what netizens call “the peak of his debut” and became a specially appointed associate professor as soon as he graduated.
Shen Dongsheng, a counselor at Hangzhou Electric Power Company, believes that:
In recent years, the requirements for the appointment of talents in the school have risen all boats, and it is not easy to become a specially appointed associate professor as soon as the doctor graduates.
But under such a halo, what is indispensable is Zhang Zhiwei’s hard work and efforts.
Published 19 SCI papers
According to the promotional materials for the selection of the “Top Ten College students” of Hangzhou University of Electronic Science and Technology in 2022, Zhang Zhiwei published a total of 19 SCI papers during the 5 years of master’s degree.
He has published more than 10 SCI papers as lead author, nine of which have been published in journals of the IEEE Association.
Of course, these papers also include the research results of hybrid EFJ power amplifier and impedance frequency modulation.
In 2020, under the guidance of mentor Cheng Zhiqun and others, Zhang Zhiwei developed a new hybrid continuous stage EFJ power amplifier to amplify the carrier.
Previously, Doherty power amplifier (DPA) has been widely used in base stations because of its simple structure and low cost. However, the traditional DPA has some inherent disadvantages, such as narrow bandwidth and only the output back-off range of 6dB.
The load impedance of the EFJ power amplifier proposed by Zhang Zhiwei and the team has not only the similar variable imaginary part of the traditional continuous power amplifier, but also the inconsistent real part.
Therefore, the EFJ class power amplifier can effectively combine the high energy efficiency of the EF class power amplifier and the large bandwidth of the continuous class J power amplifier under specific conditions, which greatly makes up for the shortcomings of DPA.
In 2021, Zhang Zhiwei and Vincent Fusco from Queen’s University in Belfast, UK, published papers on impedance frequency modulation on IEEE Transactions on Circuits and Systems II.
This is a new method to design multi-band power amplifier: a coupler is used as the output circuit of the amplifier to realize multi-band impedance conversion.
Double & nbsp; couplers
By combining the periodic impedance trajectory and the impedance space of EFJ power amplifier, the required working frequency can be obtained in real time.
At present, Zhang Zhiwei and his team are studying the technical iteration of millimeter wave communication chip version 3.0.
Zhang Zhiwei said:
It is hoped that our research results can realize the substitution of domestic chips.
One More Thing
The heated discussion caused by Zhang Zhiwei’s refusal to stay in school with an annual salary of 600,000 yuan, in addition to the content mentioned above, there is actually another voice.
Some people think that the salary of 600,000 yuan offered by big manufacturers to Zhang Zhiwei is not very high:
Before the Internet casually a fresh graduate 400000 +.
Others, from the school’s point of view, think that “professors’ salaries are too low”:
So what do you think of this?
Links to papers: