ZTE CDMA WLL Solution

In recent years, fixed-line operators have faced more and more pressures such as slow growth of fixed-line phone subscribers, considerable decrease of ARPU, increasing demand on mobility, no upgrade routes for original radio technology, and high network construction cost caused by the private land ownership system. Upon continuous innovations in wireless technologies and years of experience in wireless network construction, ZTE improves its CDMA WLL solutions with advanced and cost-effective mobility and roaming restriction functions to solve the above problems.

There are two systems for implementation of universal telecom services: wired access and wireless access systems. Compared with wired access, wireless access does not require digging trenches or setting up posts for fibers & cables. The fast site deployment and convenient maintenance make it very useful in areas with long distance and wide coverage. Among the wireless technologies, CDMA adopts 3G standards, spread spectrum technology, FEC channel performance improvement, high anti-interference capability, and diversity reception technologies, so it has wider coverage radius, less sites needed, faster construction speed, less maintenance workload, lower operation, administration, and maintenance (OAM) cost, and easier technical upgrade. For this reason, the adoption of CDMA wireless access solution can help telecom operators minimize CAPEX and OPEX.

The applications of CDMA WLL system include but are not limited to:　

·Areas and even middle or large cities where fixed-line phone service is charged much less than mobile phone service

·Last mile access

·Areas with saturated wired lines, where the wireless system can be used to boost subscriber capacity

·New urban business districts and resident areas, where the demand for phone communication is large, and the construction of a fixedline phone network is costly and takes long time

·Countryside and rural areas with sparse and discrete subscribers where it is difficult and costly to install cables.

· Areas with geographical or climatic constraints, for example, deserts, islands, rugged mountainous areas, and areas enmeshed with waterways, where the installation of cables and overhead lines is greatly hampered

·Areas where a communication system is urgently needed for temporary purpose. For example, large construction sites, great sport event in a stadium, exhibition, emergency rescue, all of which require an emergent communication access.

Figure 1 CDMA WLL Application Scenarios

As the largest CDMA equipment provider in China, ZTE has committed to the R&D of new CDMA technologies and services for years. Backed by its mature and leading technologies, powerful network planning capability, and a global technical support system, ZTE can quickly provide professional and cost-effective total CDMA WLL network solutions to customers already covering over sixty countries around the world.

Advanced All-IP Technology

As an active advocate of All-IP technology, ZTE takes the lead to implement Ap interface as well as TrFO and RTO functions that will greatly save bandwidth and vocoder resources at the A interface. Theoretically, a maximum of 80% transmission bandwidth and over 30% vocoder resources can be reduced.  　

Multiple Network Solutions

According to the requirements and actual conditions of the existing networks, ZTE provides CDMA WLL solutions based on A interface and V5.2 interface in compliance with the CDMA2000 protocols, making them easily evolve to mobile networks. More over, ZTE can provide NGN+CDMA WLL network solutions.

Figure2  A/Ap Interface Based ZTE CDMA WLL Solution

Figure3 V5.2 Interface Based ZTE CDMA WLL Solution

By comparing the two networking modes, the A/Ap interface based solution provides more diversified value-added services (for example, one number for two phones and location-based service), a better service expandability and an easier evolution toward mobile networks. The V5.2 interface based solution relies on the services provided by wired network switches.

Full Range of BTS Series

ZTE rolls out a full range of BTS series that can satisfy the coverage requirement of CDMA networks.

• Large-capacity indoor macro BTS
• Large-capacity indoor compact BTS
• Outdoor macro BTS
• Micro BTS and Remote RFS

Figure 4 BTS Series

Full Frequency Bands Supported

·ZTE CDMA WLL system provides multi-frequency products including 450MHz, 800MHz, 1900MHz, 2100MHz and AWS.

·BTSs of different frequencies can be connected to the same BSC, and the same BTS can simultaneously support different frequency configurations, thus meeting the multi-frequency networking requirements.

OTASP and OTAPA Supported

ZTE CDMA WLL system supports remote service provisioning via the Over-The-Air Service Provisioning (OTASP) technology, which makes it easy to operate. In addition, with the Over-the-Air Parameter Administration (OTAPA), customers needn’t go to the business hall and the maintenance personnel can modify the terminal parameters via the air interfaces. In this way, the workload of terminal maintenance is greatly reduced.

Intelligent System Parameter Adjustment

ZTE CDMA WLL system can sense BTS load changes and the quality status of the wireless environment where the terminal is located, and dynamically adjust the related radio parameters, including control channel gains, initial transmitting power of the forward fundamental channel, and access parameters. The BTS coverage can be maximized while guaranteeing the QoS.

Flexible Networking and Transmission

ZTE CDMA WLL system supports multiple flexible networking modes, such as star, chain, ring, and hybrid modes, which can easily achieve the application of “one link through”, that is, when a transmission link is deployed, a number of BTSs can then be deployed along the link including railways or highways to attain the maximum coverage at the lowest cost and in the shortest time.

In practice, multiple networking modes can be combined to meet the specific requirement. In addition, ZTE CDMA WLL network supports multiple transmission modes, including microwave, BWA, satellite, coaxial cable, optical fiber, HDSL and Ethernet. The Abis interface supports at least 64 Kbps transmission bandwidth and sharing transmission equipment with other existing networks. In this way, it facilitates operators to fully utilize the existing transmission facilities to construct their CDMA WLL networks. ZTE’s satellite transmission solution has been successfully deployed in Hainan Province of China and other countries such as Peru and Mongolia.

Perfect Mobility Restriction

ZTE has rich experiences in the CDMA WLL system, and an in-depth understanding of mobility restriction. The CDMA WLL system can restrict subscribers’ mobility within the following scopes:

•  Mobility within one sector
•  Mobility within one BTS
•  Mobility within multiple BTSs
•  Mobility within the areas under the control of one BSC
•  Mobility within the areas under the control of multiple BSCs/MSCs
•  Mobility within the whole network

The system has the following features:

• Full compliance with the standard interfaces
• The mobility restriction solution does not have special requirements on terminals. The only requirement is proper parameter setting in the system.
• For the subscribers with different mobility levels, different services and charging rates can be provided.
• There is no constraint for the home network, which makes it easy for subscribes at the border areas to make phone calls.

Smooth Evolution and Capacity Expansion

· All-IP architecture: ZTE CDMA WLL system adopts the All-IP architecture. It complies with the trend of technical development, and can smoothly evolve to NGN. It maximally protects operators’ investment.

·Smooth upgrade: The BSS can support CDMA2000 1xEV-DO through software upgrade and by adding related channel boards that support EV-DO.

·Smooth capacity expansion: ZTE CDMA WLL system adopts modular design, ensuring smooth capacity expansion in a building block mode.

Widespread Applications

ZTE is committed to constant research of digital access communications. By the end of June, 2007, ZTE has successfully deployed over 100 million lines of its infrastructure CDMA equipment in over 70 countries for about 120 operators. Its CDMA products feature low cost, wide coverage, high QoS, and easy maintenance and become an ideal choice for operators to build their wireless access networks.

Figure 6  Global Presence of ZTE CDMA WLL