Series: Inside the Minds of Sony’s Corporate Distinguished Engineers #3 Makiko Kan

Connecting Two Worlds on the Boundary of Analog and Digital

Sep 3, 2021

In this series, Sony’s top engineers discuss their careers, research, and their ideal profile as an engineer at Sony.
In #3, we hear from Makiko Kan, an expert in error-correcting code theory.

Corporate Distinguished Engineer
Sony certifies its engineers as "Corporate Distinguished Engineer" who formulate and execute technology strategies while identifying signals of change, and support the development of talent in order to ensure Sony’s sustainable growth.

  • Makiko Kan

    General Manager
    Distinguished Engineer
    Tokyo Laboratory 23,
    R&D Center
    Sony Group Corporation

From book girl to mathematician. A teacher’s life-changing words

Makiko Kan was born in Aichi prefecture, central part of Japan. As a child, she loved writing stories and would spend hours thinking about novels and other creative works. A teacher’s words during a high school class would set the direction of her life.

My dream when I was very little was to become a “person who writes stories.” I would let my imagination run wild and draw picture books which I would then put into neighbors’ mailboxes (laughs). I enjoyed thinking about topics like novels and Japanese language classes, which let you use your imagination, rather than arithmetic which require repetitive practice.

I was first inclined to go down this path when I heard the words, “Your solution is beautiful.” That is what my high school teacher said to me during a math class. It wasn’t about whether I had solved the problem or not, but rather that my perspective of solving it was beautiful. This adjective still lingers in my mind, and it was what spurred my interest in mathematics. Coming up with an elegant way to reach the same answer while cutting out the fluff is something I still value greatly.

At university, I majored in number theory. Called the “queen of mathematics” by the greatest 19th-century mathematician, Carl Friedrich Gauss, it is a proud field that stands apart from other branches of mathematics. It is far more exciting and stimulating than I would have imagined in high school. I proceeded to a doctoral program and went to the UK on a one-year exchange program, where I got the chance to study number theory in greater depth.

At the university I was attending, the number of students in my field was limited. I thought it would be detrimental to stay holed up inside the campus, so I actively participated in off-campus study groups and social events. I felt it would be difficult to expand my world if I didn’t hone my skills through “interleague matches,” regardless of whether I’d stay in university or work in industry.

At an algebraic roundtable in one of those study groups, I happened to meet a Sony employee. This made me consider working at the company.

As a child, she enjoyed creative work more than arithmetic

The fateful encounter at the study group made her decide to work at Sony. She would begin her pursuit of error-correcting code theory using her knowledge of number theory.

What made me decide to join the company was becoming certain I would be able to do what I wanted if I were to work with the Sony employee’s team after witnessing their way of conducting research. Despite the fact I was a mere student, they would respond to my questions and feedback sincerely and discuss them with me on an equal footing. I could sense a free and open-minded workplace atmosphere. I also participated in their party and found the good balance between work and play appealing.

When I joined in 2000, there were two main areas where a background in number theory could be useful. The first was cryptography. Telecommunication companies were engaged in a fierce competition to use elliptic curves, a concept in number theory, to research and develop cryptographic communication systems. The other area was algebraic geometry codes, an example of error-correcting codes. Error-correcting codes are necessary to remove noise that occurs in signals during digital communications. It was clear that demand in this field would only increase along with the acceleration of digitalization. At the same time, working in this field requires a deep understanding of mathematics. The fact that I was able to take part in this research after I joined the company was fantastic for me personally.

Three years passed by in a flash as Kan immersed herself in the study of error-correcting codes. Afterward, she would use the fruits of her research as a foundation in shifting the focus of her work to broadcasting standardization.

Since around 2003, with the advent of satellite broadcasting, discussions on the standardization of second-generation digital broadcasts intensified, mainly in Europe. Just as I had gotten used to working at the company and accumulated some knowledge on error-correcting codes, Sony launched a project to propose broadcasting standards to each country.

I didn’t have a lot of knowledge on broadcast standards myself, but as a matter of fact, error-correcting codes and broadcast standardization are closely intertwined. The sender and receiver of a signal across companies use different devices — this is true both for broadcasts and telecommunications. If there are no established standards, data cannot be sent and received correctly. Using error-correcting code technology to remove noise from digital signals would serve to improve transmission quality during the transition away from analog broadcasting and communications. At the same time, securing intellectual property rights in the field of broadcasting standards would be extremely important for the television business.

Creating a new broadcast system for the world.
The path to realizing the dream

Sony’s strategy to lead the standardization of each country’s broadcasting had begun. With her proposals in hand, Kan traveled around the world.

Our proposition to the entire world was to implement LDPC (Low-Density Parity Check) codes, a type of error-correcting code, in digital broadcasts. We traveled Europe and the U.S. with our dream of creating a new broadcasting system for the world and got them to acknowledge the superiority of our technology after heated discussions and direct negotiation. Though I was still quite young, I conducted presentations as Sony’s representative and participated in negotiations. I believe that being able to participate in standardization activities even though I was assigned to the semiconductor department at that time is something that would not have been possible at other manufacturers. The deciding factor which got our proposals accepted was our consideration of circuit design and costs associated with post-adoption implementation of LDPC codes into actual products. It allowed us to quickly proceed with commercialization.

Our strength lay in utilizing Sony’s decades of expertise as a television manufacturer and academic code theory to define and propose the requirements for broadcasting and televisions by considering them in tandem, and this experience would not have been possible without our team’s background at Sony. The fact that I was able to take part in the standardization of broadcasting systems was a major boost to my self-esteem.

Left: Participated in a meeting held in Munich, Germany, to standardize broadcasting in Europe / Right: At the in-house standardization forum

The standardization activities spanned a period of ten years. During that time, Kan would take on additional roles. One was as a leader, the other as a working mother.

I first became a team leader in, I believe, 2005. I can read academic papers and conduct research on my own, but mere understanding is not enough to produce results in the field of semiconductors. In order to produce technology which can actually be applied to circuits, it is important to work as a team on hardware implementation. Since that time, I would always keep the team in mind when working, instead of focusing on myself. There were few women at the organization, so my colleagues might have been worried about me. I, however, had no qualms about becoming a leader and assuming a managerial position.

That being said, I was going through life events at the time including giving birth and child raising, and my life was very challenging. You often hear about work-life balance, but in all honesty, I had no time to consider my work and my life separately. I could not work overtime because I had to pick up my child from kindergarten. Although I would come home by 6 PM, I could not switch from work-mode to family-mode and would always think about work while doing household chores. The opposite was also true — I would worry about my child while I was working. My daily life was a blend of my work and my household, and I would manage it while figuring out how to optimize my tasks.

Work is Life, Life is Work. “It was difficult, but certainly not a negative experience,” Kan recalls. What does she mean?

I believe there are many people who struggle to balance their career and family life, not just at Sony. But child raising can help you discover things beneficial to your work. One example I won’t forget was when the kindergarten teacher was preparing dance music to be used at an event. She was setting up the cassette tape by fast-forwarding and rewinding it repeatedly. She could have done it much more efficiently, with just one button, thanks to digitalization. There are many settings like that where taking advantage of current technologies is still not the norm. Encountering them allows you to see needs you would not notice otherwise, I believe.

Opportunities to discover such needs may not be available to people in other stages of their lives. But I got a chance to learn about them, which ended up benefitting my career.

I have been able to share my experiences with female engineers within and outside the company on several occasions, but I am always careful not to say things like,

"Let's always be perfect in every area." Obtaining a variety of knowledge and experiences is useful both for your family and work. Staying positive is important. Instead, I tell them to “Do your best and never give up.” The number of female engineers in the entire industry is limited, and Sony’s numbers are still not at a level I consider satisfactory. From the perspective of benefiting from diverse opinions, I would like to contribute to creating a workplace that is attractive to women.

With her family

Working on a global stage and beyond

Since the cooling down of broadcast standardization activities in 2017, she has been engaging in sensing-related research.

I supervise a team of several dozen members that is engaged in sensing-related research and development of technologies ranging from image sensors to millimeter wave radars. The bulk of my own work consists of signal processing and system architecture for sensing, AI, and IoT.

There is also an interconnection between error-correcting code technology and AI. Concepts from neural network theory are used for the decryption of LDPC signals in broadcasting. I have been using my expertise from working on decoder circuits for broadcasting equipment to develop technology that integrates deep neural networks into processors. To give an example, in LDPC signals for broadcasting, erroneous 0s and 1s created due to noise are decoded through correlations based on how likely they are to be a 0 or a 1. This is the same mechanism used to determine how likely it is that a given picture is of a dog or a cat.

I am also involved in developing technology that ensures accurate and efficient data conversion and signal processing for sensors. This technology will be used in many of Sony’s businesses with the advent of digitalization and IoT. When I look back upon my work so far, I feel that ever since the beginning, I have been working at the boundary between the real and virtual, the analog and digital worlds. I believe the value of Sony’s businesses will also be determined according to how well the connection between these two worlds is managed.

It has already been established that we can reach the theoretical maximum capacity information transmission rate for LDPC signals. Thus, my future research will be focused on applying ideas and concepts to existing circuit products at a realistic cost and scale rather than the theoretical pursuit of greater functionality and efficiency.

The greatest appeal of working as an engineer at Sony is the wide range of businesses and the free and open work environment.

When I joined Sony, it was mainly an electronics manufacturer. But now the company handles a wide range of businesses, from entertainment such as pictures and music to finance. The technology I specialize in, error-correcting codes, as well as other fields in mathematics, can be combined with different businesses to produce unexpected innovations. This has served as an inspiration for me, and I believe this is a company with the potential not just to succeed on a global stage, but to go even beyond that.

Also, it is a very free and open workplace where differences in age and gender, nationality, and rank are overcome and opinions are heard. I can work as I please thanks to that.

At the same time, it has the advantages of a Japanese company. The atmosphere encourages working as a team instead of by yourself and helping each other in times of need. It combines the positive aspects of both Japanese and global companies.

Sony, with its wide variety of businesses and free research environment, allows goal-oriented people to achieve outstanding results. Conversely, it always requires us to be aware of what they can accomplish with this freedom. I would like to continue doing my best together with my colleagues to achieve our dreams and realize our vision.

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