Growthstock Pulse Editorial
As mobile data communications transition from 5G to 6G, improving communication quality in high-frequency bands has become a critical industry-wide challenge. Current data demand is growing at 200% annually, requiring next-generation networks capable of handling 20 to 100 times more traffic than today’s infrastructure.
While frequencies above 28GHz enable high-capacity, low-latency communications, these high-frequency radio waves exhibit light-like propagation characteristics, resulting in shorter transmission distances and easy obstruction by buildings and obstacles—a fundamental challenge that threatens 6G deployment.
To address this challenge, Tokyo-based Visban has developed proprietary repeater technology using glass substrates combined with AI-controlled mesh networks. In September 2024, the company secured Series A round from University of Tokyo Innovation Platform (UTokyo IPC), Dai Nippon Printing (DNP), and Mitsubishi Materials, and is currently preparing for proof-of-concept demonstrations.
Dr. S.B. Cha, the company’s CEO, first came to Japan 29 years ago when he was appointed Vice President of Cambridge Display Technology, a Cambridge University spinoff developing polymer organic EL display technology (acquired by Sumitomo Chemical in 2007). Since then, he has served as a professional CEO for multiple companies in Japan over many years.
As a serial entrepreneur with extensive experience, Dr. Cha founded Visban in Japan in September 2022, motivated by the COVID-19 pandemic to realize his technological vision. The company currently leverages Japan’s early-stage startup ecosystem advantages while targeting global market expansion.
Technical Challenges of Explosive Data Demand
Smartphone proliferation is expected to drive global mobile data traffic to 10 times current levels by 2030. However, existing communication technologies are approaching physical limits, making fundamental technological innovation urgent. The explosive growth in global data demand is forcing the wireless industry to pursue unprecedented technological innovation.
The proliferation of smartphones, tablets, and IoT devices is rapidly increasing device counts annually, while data consumption per device grows exponentially. Consequently, global data demand continues growing at an extraordinary 100% annual rate, reaching scales that current communication infrastructure cannot adequately support.
While the wireless industry prepares next-generation networks to meet this demand, the technical transition faces significant hurdles. Current 5G technology primarily uses frequency bands below 3GHz, but next-generation systems require a dramatic frequency jump to 6-28GHz. This represents the industry’s largest frequency jump in history, creating both anticipated and unexpected problems. More critically, many solutions initially envisioned by the industry have proven far more expensive than expected.
Frequency bands above 28GHz present technical dualities. They enable high-capacity data transfer and extremely low latency, making them ideal for applications like robotics and autonomous vehicles that cannot tolerate even minimal delays. However, physical constraints pose serious challenges. High-frequency signals struggle to penetrate buildings, have limited range, and are easily blocked by rain, trees, vehicles, and other obstacles.
Cha explains,
Rain, trees, cars—all of these can cause blocking or interference. In reality, you’ll end up with many dead zones and slow spots. Remember when the iPhone was first introduced? There were places with good coverage, but also many places with poor coverage. Without Visban’s technology, we’re basically going back to that situation.
Traditional solutions involving base station multiplication are not realistic. Looking around Tokyo, many buildings already host base stations, but supporting high-frequency bands would require 20-40 times more base stations. Beyond the high costs of base stations themselves, this creates challenges in securing installation sites, construction expenses, and aesthetic concerns.
Revolutionary Network Solution: “V-Mesh”
Current communication paradigms feature smartphones communicating directly with base stations in a simple structure. While technically possible for 28GHz high-frequency millimeter-wave networks, this approach has significant practical limitations in the 6G world. Stable connections can only be maintained within extremely limited ranges of 20 meters from base stations, with connection likely lost at 25 meters. Building base stations every 20 meters is practically impossible.
To solve this challenge, Visban has developed an approach that constructs “sub-networks” between base stations and smartphones. Called “V-Mesh,” this solution deploys mesh networks or spider web-like device networks around base stations, with each node receiving, amplifying, and retransmitting signals.
This multi-hopping technology amplifies signals with each hop, progressively extending transmission range. This not only expands base station coverage but, more importantly, enables filling “non-line-of-sight” dead spots. Even when smartphones cannot see base stations directly, signals can be routed around obstructions via multiple relay points.
Traditional base station multiplication required 20-40 stations per square kilometer, but V-Mesh enables equivalent coverage with a single base station. This achieves 90% capital expenditure reduction while dramatically improving communication quality.
Visban’s greatest technical differentiator for realizing V-Mesh is proprietary technology for constructing high-frequency devices on glass substrates. Currently, Visban is the only company worldwide capable of implementing high-frequency devices on glass substrates, creating a decisive competitive advantage. This technology achieves significant cost reduction and performance improvements compared to traditional PCB (printed circuit boards), realizing costs one-tenth that of base station implementation.
Cha explains,
Compared to traditional PCB substrates, the technical advantage of glass substrates is that the entire manufacturing process is more efficient. Therefore, the cost of making these devices is significantly lower than PCBs.
Glass substrates are also lighter, more stable, and more resistant to warping and damage. At high frequencies, antennas and circuits become much more sensitive to distortion, which converts to noise and heat. Building V-Mesh devices requires extremely stable platforms.
The company has established strategic partnerships with Japan Display, with Visban handling design and Japan Display managing manufacturing in a division-of-labor structure. While glass substrate development involved complex technical challenges, Visban has successfully developed proprietary design rules for efficiently placing up to 12 different circuit layers, shields, and ground planes within limited glass substrate layers. Manufacturing timelines are proceeding smoothly, with the first glass devices scheduled for completion next month.
Another core V-Mesh technology is an AI-powered dynamic control system. A system called the “Orchestrator” handles network-wide optimization. V-Mesh forms sub-networks of up to 100 devices around base stations or satellite gateways, but these devices don’t communicate directly with each other. Instead, they interact with the Orchestrator, which aggregates status information from all devices and sends optimized instructions to each device.
The Orchestrator’s instructions are highly technical and precise. Each device’s antennas use phased array technology (coordinated antenna control for precise beam steering, also used in Starlink antennas), forming narrowly focused beams. This simultaneously achieves extended communication range and improved power efficiency.
In network environments with 100 devices, communication path combinations become enormous, so the system compares coverage performance across different configurations, learns by correlating results with contextual data, and derives optimal routing.
However, realizing this revolutionary technology involves advanced technical challenges. High-frequency circuit design on glass substrates, AI control algorithm optimization, mass production process establishment—multiple specialized fields require simultaneous technological innovation. Nevertheless, the company is systematically clearing these challenges and plans to demonstrate technical feasibility through next year’s proof-of-concept experiments.
Current V-Mesh networks comprise 4-6 devices for evaluation, but next year’s demonstrations will test 10-device scale network operations.
Born in Japan, Growing Globally
In the previous round back in September of 2024, the company secured 450 million yen (about $3 million US) from UTokyo IPC, DNP, and Mitsubishi Materials. UTokyo IPC supported business plan development even before Visban’s founding through their 1stRound startup support program. Relationships with other strategic investors are expected to develop gradually.
Each investor’s interests differ clearly. Mitsubishi Materials is examining whether existing materials can supply Visban devices or new material development possibilities. DNP takes a broader perspective, evaluating both how this technology might contribute to internal operational efficiency and potential for entering new business domains with competitive advantages.
While strategic investors are currently all Japanese companies, Visban’s primary markets are actually overseas, not Japan. Japan possesses world-class wireless and communication infrastructure, is geographically compact, and has populations concentrated in major cities. Consequently, over 95% of households have fiber optic access—starkly contrasting with the US’s sub-30% figure.
Therefore, Visban’s technology targets regions with relatively low fiber penetration and rapidly growing data consumption, where wireless solutions are more economically advantageous than fiber deployment. Accordingly, the next funding round is considering US investor-focused strategies.
Cha explains,
Visban is different from other companies I’ve managed. In previous companies, I was a hired CEO. While I was a management professional, I wasn’t a founder, so I didn’t worry much about equity dilution. But at Visban, as a founder, I care greatly about dilution. Therefore, I’m timing fundraising around value inflection points.
Our value inflection point is quite simple. We have plans for field demonstrations using existing 28GHz networks. It’ll be private networks, but we’ll show the world that our solution works. If we can extend that network’s range and fill dead spots, that’s obviously a major value inflection point for us.
Visban expects the next round to be a reasonable Series B by the US standards, around $25 million. This would be large for Japanese Series B standards, so the company will likely seek lead investors in the US and fill the round with Japanese and US investors.
Visban seeks US investors because investor support with excellent networks for US market customer acquisition is extremely effective for business growth. Particularly, if the company can bring aboard US corporate venture capital (CVC) familiar with this industry, technology commercialization would be significantly accelerated.
Cha notes,
Our technology will be developed in Japan, demonstrated in Japan, and manufactured in Japan, but will probably be sold primarily outside Japan, at least initially. Strategically, that’s our shortcut to growth.
Satellite Communications Synergy and Future Vision
Recently, the communications industry has focused attention on “D2D (Device-to-Device) satellite communications” as next-generation revolutionary technology. Unlike traditional satellite communications requiring dedicated antennas and terminals, this breakthrough technology enables ordinary smartphones to communicate directly with satellites. In Japan, KDDI has already launched “au Starlink Direct” service, while Rakuten Mobile plans its launch in 2026 Q4 and NTT Docomo and SoftBank plan summer 2026 service launches.
This technological revolution means smartphone communications become possible anywhere with clear sky views, even in mountainous regions and remote islands beyond terrestrial base station coverage. However, Visban focuses on how even revolutionary D2D satellite communications face the same physical constraints as traditional base stations for terrestrial signal distribution.
Regarding D2D satellite communications services announced by companies like NTT Docomo, Visban anticipates very positive long-term impacts. Direct satellite-to-mobile communications face the same physical constraints as base stations. In high-frequency bands, whether signal sources are satellites or base stations, the same challenges of line-of-sight maintenance and obstacle obstruction occur.
Cha observes,
Where satellites will be tremendously helpful is that satellites are fiber optic replacements. Ultimately, I think D2D satellite communications services will be very successful. However, when satellites move to very high frequencies for greater capacity, the same problems as terrestrial 6G base stations will occur, requiring solutions like ours for signal distribution.
We don’t care where the original signal comes from. Whether satellite or base station, Visban provides last-100-meter outdoor-to-indoor distribution. Our devices provide methods for bringing high-data-rate millimeter-wave signals into buildings, whether from satellites or base stations, then either converting to Wi-Fi or relaying directly.
Through such technological innovations, Visban dramatically expands communication infrastructure possibilities. Once commercialized, applications spanning emergency disaster communications, remote medical care in mountainous regions, real-time autonomous vehicle control, and factory IoT device control are anticipated. Particularly, regions where communication infrastructure deployment was previously difficult can now achieve high-speed, low-latency communication environments cost-effectively.
Visban provides revolutionary solutions addressing critical technical challenges in the 5G-to-6G transition through proprietary glass substrate technology and AI-controlled mesh networks. Leveraging Japan’s excellent technological development environment and strategic investor support while pursuing steady growth strategies targeting global market deployment, the company advances toward next-generation wireless communication infrastructure realization. Next year’s proof-of-concept experiments will likely become crucial turning points for global attention to the company’s technology.
The company currently actively recruits technology development partners, manufacturing partners, and sales partners. They particularly emphasize overseas market channel expansion, mass production technology establishment, and application development collaboration. For companies targeting first-mover advantages in the massive next-generation communication infrastructure market, partnerships with Visban offer high strategic value.
