Home to 378 million mobile subscribers, and with four to five million new GSM users signing up every month, China is by far the world’s biggest mobile market. And soon it may also have three different 3G standards.

Besides WCDMA and CDMA2000, the range of 3G radio technologies standardized by the ITU also contains the less widely adopted TD-SCDMA (Time Division/Synchronous Code Division Multiple Access). This third standard is receiving particular attention in China, where it is sometimes referred to as the country’s “homegrown” 3G technology.

3G licensing in China is expected to take place in the first quarter of 2006 at the earliest, with commercial deployment starting immediately after the licenses have been awarded. The final outcome in terms of spectrum allocation, and the resulting distribution of radio standards meanwhile remains to be seen. Nevertheless Ericsson announced in May that it had formed a strategic alliance with Chinese vendor Zhongxing Telecom Equipment (ZTE) to deliver solutions for the local market.

Hans Hammar, director of RAN Product Management at Ericsson China, believes the alliance puts Ericsson in an ideal market position ahead of the 3G rollout: “Our goal is to offer a competitive solution to operators with different types of spectrum allocations by presenting an enhanced 3G portfolio adapted for local needs.”

Hammar notes that the general opinion among industry observers is that the final makeup of China’s 3G landscape will include a mix of two or three radio standards: “The government is expected to award two WCDMA licenses ­­– one CDMA2000, and perhaps a bundled WCDMA/TD-SCDMA license or even a separate TD-SCDMA license. Whichever technology our Chinese customers decide to adopt, we are ready to support them

with corresponding, best-in-class solutions.”

Under the agreement with ZTE, Ericsson will therefore integrate ZTE’s TD-SCDMA Node B into its Radio Access Network, hence providing an integrated network solution. The core network is the standard Ericsson common core product.

Hammar says that operators faced with the prospect of a bundled license are in particular need of integrated, flexible network solutions. “And if an operator with a bundled license wants to expand its network along both standards, it is still possible to start out along the WCDMA path and add TD-SCDMA access capabilities later on,” he says.

Like WCDMA and GSM – but unlike CDMA 2000 – TD-SCDMA is fully compatible with Ericsson’s core network solutions.

Gearing up for the coming 3G rollout, ZTE and Ericsson completed a second round of successful field trials in September. And to further enhance and complete its TD-SCDMA offerings, Ericsson has also established a new Research and Development center in Nanjing. “The purpose is to leverage fully Ericsson’s leading technologies and solutions in 3G, as well as strong local R&D capabilities,” Hammar says.

TD-SCDMA utilizes a different portion of the spectrum from WCDMA, which is based on FDD (Frequency Division Duplex) using different frequencies for uplink and downlink. It is specially designed for the unpaired TDD spectrum, which makes it attractive to operators with unpaired spectrum allocation,” says Hammar.

In theory, TD-SCDMA is well suited to asymmetric loads such as Mobile Internet (since mobile data tends to require little uplink throughput but significant bandwidth for downloading information) but is less suitable for heavy, synchronous applications such as video telephony. By comparison, ongoing development in WCDMA – such as HSDPA – is working in favor of rendering that standard suitable for super-heavy data traffic, too.

In the case of China, the single biggest driver of TD-SCDMA development is probably the pride in developing and standardizing a “homegrown” 3G technology, which – if successful – may develop into an export technology. As Hammar points out: “There is tremendous national pride in TD-SCDMA, the development of which is driven by the Chinese government and the Ministry for Information Industry.”

Homegrown or not, anything that China chooses to do in 3G is certain to have an impact far beyond its borders.