Ultimate Network Speeds Exceed Dreams
——CSL built the world's first and fastest HSPA+ commercialized network based on SDR

Founded in 1983, CSL is the largest mobile telecommunication operator in Hong Kong and a subsidiary of Telstra Corporation Limited of Australia. CSL has launched several brands including 1O1O, One2Free and New World Mobility and kept its leading position in the mobile telecommunication market of Hong Kong.

In March 2006, CSL merged with New World Mobility and inherited the network of New World Mobility to accommodate its rapid developing business. The merger made the networks held by CSL become more complicated, as CSL now has four networks, including one GSM900 network, two GSM1800 networks and one UMTS2100 network with four core equipment rooms. The operating networks of multiple systems not only directly results in great difficulties for smooth upgrade and expansion of 2G and 3G networks, but also incurs high operation and maintenance costs due to repeated equipment investment and network complexity.

Facing the fierce competition in the telecommunication market and the emerging 3G operators, CSL felt compelled to integrate its networks. Moreover, to maintain its leadership in the Hong Kong market, CSL urgently needed to optimize the network structure, reduce operation costs and integrate the advantages of its four networks to provide convergent, high-speed and customized services.

CSL had to undertake the unprecedented mission of network integration.

Three challenges faced by CSL

Following Telstra, which has been investing generously in its HSPA-based Next GTM network covering the entire Australia, CSL is currently making huge investments to deploy over 2200 HSPA+ base stations in Hong Kong to enable peak download at 21Mbps. CSL is committed to establish its Next G brand as one of the most advanced telecommunication networks in the world.

Based on a series of careful and detailed research and inspection in respect of related technology and other key indicators, CSL finally decided to single out ZTE to carry out the full turnkey project of "Single Network" in February 2008 and the contract was signed in March 2008.

Before the network construction, CSL and ZTE were confronted by three major challenges:

Firstly, the physical environment is very restrictive. Hong Kong is an international metropolitan known for its dense high-rise buildings and mountainous, waterside and seaside geographical features. Moreover, the city is thickly populated by 6,925,000 people living on a land area of 1,092 km2.

Secondly, the existing base stations of various types made the networking construction rather complicated, because the replacement of the current network for 2G/3G involves not only the replacement of existing sites, but also the acquisition of new sites.

The third challenge came form the tight schedule. No contractors had ever completed such a turnkey project of thousands of base stations within one year's time. However, CSL requested ZTE to break the historical fastest deployment record of 2 years under similar circumstances.

Joint efforts in delivering high-quality and customized networks

Faced by all the critical challenges, ZTE pooled its rich experiences accumulated from all the previous global projects and jointly contrived with CSL the "three phases" strategy, which successfully guaranteed the smooth progress of the CSL project from site replacement to the overall upgrade of the core network. 

Phase 1 was to rebuild the core network and replace 2,100 3G base stations at 2,100 Mhz; Phase 2 was to replace 2,800 base stations, including 2G 900/1,800 Mhz and 3G 900/2,100 Mhz; Phase 3 was to comprehensively upgrade the core network.

CSL was deeply impressed by ZTE's high quality, fast and end-to-end technical and engineering delivery capability.  ZTE designated a strong delivery support team to understand the requirements of the client and prepare an appropriate technical solution; the overall network planning and base station design capability was evidenced by the implementation speed of 400 base stations/month by nine subcontractors; the design, construction and network quality assurance systems were strictly followed.

Under the great pressure of time and workload, ZTE relied on its global resources and built up a professional team including 1,500 technical experts, 1,000 subcontractor's personnel and dozens of project management experts, who were dedicated to this high quality broadband mobile communication network. 

CSL and ZTE reached the understanding of "high priority and close collaboration" regarding the cooperation in the delivery. The issue escalation and resource safeguard platform was based on the meetings between the two sides at levels up to the presidents. The two sides had personnel work in the same buildings or neighboring buildings. The instant communication helped the two sides set up a strong and harmonious organizational structure.

Breaking records through innovations

By adopting the SDR base station solution, CSL's next generation network performance was greatly improved. The overall network coverage was even better than the 900M GSM network.

All these are attributable to ZTE's innovative application which ensured then indoor signal coverage in big and complex buildings and harmonized both indoor and outdoor signal coverage. The overall network coverage was significantly improved by 5-6dBm. Based on the satisfactory user experience, CSL launched a campaign of "Tomorrow's Technology>>>Today" for commercial promotion.

The wise selection of the SDR solution saved a substantial amount of OPEX (Operating Expense). CSL's OPEX was reduced from HKD 225.4 million to HKD 86.9 million a year, saving HKD 138.5 million.

To further consolidate its leadership in the mobile communication market in Hong Kong, CSL has decided to deploy a LTE network to offer the fastest speed, highest capacity and best quality network. Convinced by the superior work of ZTE, CSL continued to cooperate with ZTE on LTE project, only half a year after HSPA+ deployment. In September 2009, CSL and ZTE jointly held a LTE demonstration to the public. In the demonstration, the downlink rates up to 100Mbps were displayed. The commercialized LTE which started this year was seen as the prelude of the march to LTE era.