VNPT Technology masters the technology of manufacturing Small Cell

VNPT Technology is one of the first domestic units to master the technology of manufacturing small cell, which can be used to supplement and improve network signals for Macro Cell.

 

Currently, the Vietnamese telecommunications network is using large traditional stations (Macro Cells) to receive and transmit signals. These stations are often expensive and prone to signal degradation if the building density is dense or the number of users in an area is too large. Meanwhile, the growing demand for user data due to the emergence of new business models using mobile networks along with the deployment of millions of internet-connected devices (IoT) requires carriers to have a more reliable and high-speed data transmission solution.

In that context, Small Cell promises a cost-effective solution to this problem. Since 2019, in a high-tech cooperation program with the Ministry of Science and Technology, VNPT Technology has started to develop a small multi-technology WiFi/4G base station device.

This is one of the first Small Cell devices successfully researched and developed in Vietnam. Compared to traditional stations, Small Cell devices have more flexible deployment capabilities – less cost; easily mounted on street lights, power poles, inside buildings and many other structures; and provides a coverage radius of up to 300m.

Small Cell devices are not a replacement for the Macro network but are added to improve the Macro network signal. MSc. Nguyen Van Trung - Director of VNPT Technology's Software Technology Center and project leader - said that in two months of testing on Vinaphone, the device has helped increase transmission capacity coverage in the region up to 2 times and the maximum transmission speed reaches 300 Mbps.

It is expected that in 2021, VNPT Technology will work with ANSV to deploy thousands of Small Cell devices at different locations across the country.

The Small Cell device market has exploded since 2015, with the participation of a series of well-known telecommunications equipment suppliers such as Ericsson, Nokia, or Huawei. Commercial projects have also begun to appear to deploy small cell systems in the country.

Mastering the technology has made VNPT Technology one of the first suppliers in Vietnam capable of replacing imported Small Cell equipment, contributing to ensuring national network security.

All-in-one optimization

Small Cell devices look like a miniature version of the Macro Cell station but are not exactly the same. They all share the same core technology, including hardware, radio, baseband signal processing technology, and 4G LTE network protocol.

The difference is mainly in the broadcast capacity, coverage capacity and the number of simultaneously served users. Small Cells, as the name suggests, have a much narrower coverage (referred to as 'cells') than Macro Cells (several kilometers) and are also capable of serving a more limited number of users (<100 people) compared to large Macro Cell stations (about 1,000 people)

Therefore, Small Cell is usually smaller in size and integrated "all in one", including antennas located inside the box, instead of large external antennas like traditional stations. Even, the Small Cell device researched and developed by VNPT Technology is also integrated with Wi-Fi access technology (standard 802.11ac) that Macro Cell devices do not have.

Mr. Nguyen Cong Anh, Deputy Director of the Hardware Embedded Center, who is responsible for managing this product line, explains: “Because the frequency spectrum for mobile networks is limited, so when user demand exceeds that beyond the system's capacity, the device must accommodate by reducing data traffic on the 4G mobile channel and increasing bandwidth usage on the WiFi channel, especially when users are in densely used areas such as office buildings, commercial centers, ..”

To achieve that, engineers must find a way to "pack" both 4G and WiFi technologies into one box by applying optimal design principles on both hardware and software. Each of these components must ensure dual functionality, i.e. work seamlessly when switching between different technologies and bands.

VNPT Technology's engineers said the technological challenge was huge because at that time, 4G LTE base station technology was relatively new to the company, even though they had previous experience in WiFi technology development, which has certain similarities in radio technology and LTE signal processing.

After developing and manufacturing the first test version, the device still has not reached the highest technical quality as expected. The team of engineers had to conduct tests in many consecutive rounds, with a series of discussions and seminars within the company and with domestic reviewers and critics - including the Institute of Electronics and Telecommunications of Hanoi University of Science and Technology and the Faculty of Information Technology of Hanoi National University - as well as foreign experts, before the final product is released.

They have also worked directly with the world's leading source technology company Qualcomm to develop embedded software on its chipset, to process 4G signals, WiFi and route data to the core network.

Beside the above basic features of LTE, the developers of VNPT Technology also revealed a new technique that they have "improved at the design level and are ready to develop and integrate into devices in the future". It is a carrier aggregation technique between WiFi and 4G signals.

Normally, when going through an area with WiFi and 4G waves, the user's mobile device will automatically prioritize a technology - usually WiFi - regardless of whether the signal is stronger or weaker. However, if the base station is capable of carrier aggregation, it will calculate and adjust the data flow for parallel transmission on both WiFi and 4G channels in an optimal ratio (eg 3:7 or 4:6), to help users get the highest transfer rate.

Compared with some Small Cell products of the same type from abroad, there are not many devices that provide the same feature of multiplexing as VNPT Technology.

Inheriting 5G technology

Not only mastering the technology of manufacturing Small Cell devices, VNPT Technology also builds solutions to manage those devices.

Typically, as device density increases, the burden on device management, logistics, and data processing increases. It requires solutions that automate multiple processes instead of manual work, such as real-time performance management, monitoring and analysis processes, and more.

Therefore, the company also developed a monitoring and control management software system (HeMS) capable of handling 100,000 devices simultaneously. In addition, to reduce interference and signal overlap between cells, engineers also integrate self-organizing network software (SON) to detect errors, optimize and automatically configure replacement cells for nearby damaged cells.

VNPT Technology's representative emphasized that mastering the hardware and software designs, and cooperating with reputable source component suppliers, has helped them close the telecommunications equipment manufacturing process and minimize security holes, ensuring system reliability for 4G carriers.

Although 5G and 4G technologies are different, the basic design principles from signal processing to network protocols or carrier aggregation are still legacy. Therefore, mastering Small Cell devices for 4G networks will be an important step to help them inherit more easily in the process of mastering Small Cell devices for 5G networks in the near future, Mr. Nguyen Van Trung emphasized.

Project "Research, development and production of WiFi/4G multi-technology small cell", code CNC.11.DAPT/19 by VNPT Technology company from 2019-2021 under the High-tech Development National Program by 2020 is managed by the Ministry of Science and Technology.

For more information about S&T Programs, contact the National Science and Technology Programs Office at: http://vpctqg.gov.vn/