Huawei has presented a special award to Turkish professor Dr. Erdal Arikan, the inventor of polar codes for 5G, in recognition of his outstanding contribution to the development of communications technology.
The Chinese vendor said the paper on polar codes that Dr Arikan published in 2008 defined an entirely new approach to maximizing the rate and reliability of data transmission.
In 1948, the father of information theory, Claude Shannon, calculated a limit for the speed at which we can transmit data error-free. The faster you send data, the more chances for errors are introduced. For decades, the industry has been working on ways to get us closer to that limit through a process called channel coding. Polar codes are believed to be the first channel coding scheme to bring the industry up against the threshold of Shannon's limit, or the maximum rate that data can be sent with zero error at a particular bandwidth.
According to Huawei, polar codes can significantly improve coding performance for 5G, while reducing the complexity of design and ensuring service quality.
In 2016, polar codes were selected by the 3GPP as the official coding scheme for the control channels of 5G New Radio (NR) eMBB interface, replacing the conventional turbo codes which are used in 3G and 4G. Meanwhile, the 3GPP has also picked LPDC (low-density parity-check) code, which is widely used for Wi-Fi, for the data channels.
Speaking at a media roundtable at Huawei’s headquarters in Shenzhen last Thursday, Dr. Arikan said he was surprised that this nascent coding technology was selected as the official coding scheme for 5G. He credited Huawei for taking polar codes from theory to practical application.
“Polar coding is the late comer to the scene and it’s quite surprising it’s found a role in this crowded scene of error-correction codes,” Arikan told reporters.
Dr. Wen Tong, CTO of Huawei Wireless, said Huawei started its research in 5G early 2000s and was impressed by the potential of polar codes and started investing in further research to build on Arikan’s work since 2010.
"From an engineering perspective, [polar codes] were premature technology, so it was very risky for us, but it was expected to bring high reward."
“At that time it was not easy for us to make such decision. We only knew that polar codes were theoretically possible. But we did it. We’ve had to do it bit by bit to reach current results. It’s very painstaking, and of course there were a lot of failures in between.”
Huawei’s bet paid off. Through years of focused effort, Huawei has made multiple breakthroughs in core polar code technology, the company said. For instance, the company achieved downlink speeds of 27Gbps using polar code during a field trail conducted in 2016.
Limitations
Industry watchers believe that the selection of polar coding as the channel coding technique for control channels for 5G communications system may have put Huawei at the forefront in the 5G race.
“Vendors are always jockeying with each other to maximize their IP (Intellectual Property) positions in technology standards,” said Phil Marshall, chief research officer of Tolaga Research. “This is definitely a win for Huawei.”
While polar code implementations are less complicated and more versatile than turbo codes for relatively low throughput channels, Marshall said polar codes lack the market maturity of turbo codes and LDPC and have implementation challenges at higher throughput channels.
“Control channels generally have lower throughput demands relative to data channels, which makes them suitable for polar codes. And LDPC is better suited for higher data rate channels," he said. "Until polar codes prove their worth for high throughput channels, then they will remain complementary to LDPC.”
But he said a lot of works are being conducted in the development of high throughput polar coding techniques with tenable latency performance and implementation complexity.
“If these efforts are successful, it is conceivable that the relative merits of polar codes relative to LDPC for high throughput channels would need to be reassessed,” he noted.
Increase funding on basic research
Meanwhile, Huawei said it has invested heavily in research and development over the years. The vendor reiterated its commitment to increase investment in basic research by earmarking 20% to 30% of its annual $20 billion R&D budget on basic research alone.
"5G standards are the result of a worldwide effort to drive progress in basic research and wireless communications technology,” Eric Xu, rotating chairman of Huawei said at the award ceremony.
“For these standards to take shape, it took more than 10 years of hard work from tens of thousands of scientists and engineers, along with dozens of companies around the world.”
Xu said Huawei will continue to work hard to ensure that 5G technology including polar codes creates greater value for society.
“At the same time, we hope that the close collaboration between companies and the academia, like the one between Huawei and Professor Arikan, will continue, and give rise to more scientific marvels that drive the development of the ICT industry and society as a whole."