As multiple 3G (third-generation) handset operating modes jostle for market acceptance, the Institute for Communications Research (ICR) has teamed up with semiconductor company STMicroelectronics NV to develop a silicon-based solution that will support these different forms of wireless air interface access.
Of particular interest to the research team is the new TD-SCDMA (time division - synchronous code division multiple access) mode indigenous to China, which has been accepted by the International Telecommunications Union (ITU) as the prime candidate for the low chip rate version of TDD (time division duplex) mode operation worldwide.
There are different handset operating modes for access to different wireless air interfaces such as 2G, GPRS (general packet radio service), and 3G FDD (frequency division duplex) or TDD, explained Lye Kin Mun, deputy director of ICR, formerly known as the Centre for Wireless Communications.
FDD and TDD refer to methods for dividing forward and reverse communication channels. The TDD modes allow simultaneous two-way communications between the base station and mobile terminal on the same frequency, utilizing time division multiple access methods. It is potentially cheaper than FDD modes, in which the duplex communication requires different radio frequencies for the uplink and downlink, but guarantees higher performance.
China's TD-SCDMA is one of the few 3G TDD standards accepted by 3GPP and ITU-T, said Lye. 3GPP or 3rd Generation Partnership Project is a collaboration agreement which brings together a number of telecommunications standards bodies to produce globally applicable technical specifications and reports for 3G mobile systems, while ITU-T is the ITU study group tasked with telecommunication standardization.
"Being an international standard will help to increase its potential for commercial deployment and attract more wireless players worldwide to participate in its further development and commercialization activities," said Lye.
However, with the different modes competing for market acceptance and for 3G spectrum allocation, there is growing requirement for multiple mode FDD/TDD/GPRS systems on silicon capability, which can be utilized in families of terminals for diverse markets, said Lye.
One of the challenges the research team faces in doing this involves the complexity of the 3G handset. The 3G handset is about 10 times more complex than that of 2G, he said. "The major challenge therefore is to address the increase in complexity and at the same time keep the power consumption, physical size and cost low."
"Due to the handset's requirements of small size, low power and high data processing speed, many function modules have to be implemented as ASICs (application specific integrated circuits) and chip sets, that is 'put on silicon'," he added.
The ICR-STMicroelectronics collaboration on multi-mode wireless cellular technology follows on from an earlier three-year research and development (R&D) project on the first 3G single mode FDD technology development.
ICR and STMicroelectronics first collaborated on 3G FDD single mode technology development in 1999. The earlier project resulted in a 3GPP standards compliant reference FDD design, and 3GPP standards compliant protocol stack that has been integrated with voice and audio reference applications.
The results of the project form the building blocks for the second project, which addresses multiple standards.
The thrust of the new research project is on advanced algorithm research activities, software development, and platform and silicon prototyping, thus bringing multi-mode technology to the marketplace.
Kay Das, ST's director for R&D, Asia Pacific, noted that the digital cellular market is highly competitive, with the Asia Pacific region being amongst the early adopters of 3G technology. "This strongly-focused research and development project in Singapore gives ST a strategic advantage in developing advanced products in close vicinity to the market."
The new collaboration is expected to involve 50 research scientists and engineers -- 25 from each partner -- and eight postgraduate students on attachment to ICR.
Beng Cheah, business development director of ICR, said with the second project, the institute hopes to achieve significant breakthrough in developing 3G multi-mode prototypes and complex protocol stacks, in addition to generating valuable intellectual property.