ZTE´s CDMA WLL Network Solutions

As of October 2005, over 30 million lines of related ZTE´s CDMA WLL system requirement has been operating on domestic and international communication networks, and the CDMA WLL system has entered the communication networks of 100 carries in approximately 60 countries.

    ZTE´s CDMA WLL system features low cost, wide coverage, high quality and easy maintenance. It is the best choice for the wireless access network construction of a large number of operators.

More information at:
http://wwwen.zte.com.cn:8080/English/03product/

ZTE Corporation is the largest CDMA system equipment provider in China. Its professional and cost-effective total CDMA Wireless Local Loop (WLL) network solutions are widely applied in a global context.

    The CDMA WLL system is applicable to the following scenarios:

• Countryside and rural areas with sparse and discrete subscribers.

• Areas with geographical or climatic constraints, such as deserts, islands, rugged mountains and areas enmeshed with waterways, where the deployment of cables and posts is greatly hampered.

• Areas with saturated wire lines, where the wireless system can be used to boost the increase of capacity and subscribers.

• Commercial districts and resident communities, where the demand for phone communication is large, and the construction of a wired phone network is costly and timely.

• Areas where a communication system is urgently needed for temporary purposes.
  

1 Multiple WLL Solutions to Meet Different Networking Needs
ZTE provides CDMA WLL solutions based on either A interface or V5.2 interface under the CDMA2000 standard protocols. Moreover, ZTE can provide the NGN+CDMA WLL network solutions.

    By comparing the two networking modes illustrated in Figure 1 and Figure 2, the solution based on A interface provides more value-added services. In addition, it provides a better service expandability and an easier transition toward mobile networks. For the solution based on V5.2 interface, its service offerings rely on the services provisioned by the switches of fixed networks.

2 ZTE´s Base Transceiver Station (BTS) Series for the WLL Solutions
ZTE´s BTS series products meet coverage requirements for different terrain, and help lower investment of the operators. They include macro BTSes, micro BTSes, remote RF stations, and repeaters, as shown in Figure 3.
The macro BTSes have flexible configuration that can be used in various application scenarios. The large-capacity macro BTS is able to support 24 operator-sectors in one single rack.

    The micro BTSes and remote RF stations support different power outputs of 10 W/20 W/40 W. The multi-frequency and multi-sector configuration can be flexibly expanded.

    The micro BTSes and the remote RF stations have the following features:

• They are designed based on outdoor conditions. Therefore, equipment room and air-conditioning facilities are possibly saved.

• They have small sizes, light weights, small power consumption and flexible installation (on the top of roofs, iron towers, concrete posts, etc.).

• They provide auxiliary equipment solutions of integrated power supply and transmission. Their requirements on power supply are low. The construction of auxiliary equipment is flexible.

• Interfaces are provided to implement the monitoring of power supply and other external environments and equipment.

• The construction period and difficulty are effectively reduced.
  

    ZTE´s BTS series allow different BTS combinations on a need basis and flexible application. They help implement cost-effective multi-layer conventional network coverage, indoor coverage and wide-area (including ultra-long distance) coverage.

3 Strengths of ZTE´s CDMAWLL Solutions

    (1) Support for Full Frequency Bands

• ZTE´s CDMA WLL system supports 450 MHz, 800 MHz, 1 900 MHz and 2 100 MHz, and satisfies coverage requirements for different frequencies.

• The BTSes of different frequencies can be connected to the same Base Station Controller (BSC). Moreover, one BTS can simultaneously support different frequencies (such as 450 MHz and 1 900 MHz). Therefore, the
  multiple-frequency networking requirements of the operators are fully satisfied.
  

    (2) Support for Over-The-Air Service Provisioning (OTASP) and Over-The-Air Parameter Administration (OTAPA) TechnologiesZTE´s CDMA WLL system supports remote service provisioning by the OTASP technology, which makes the service provisioning easy to operate. In addition, the OTAPA service enables subscribers to modify their terminal parameters via an air interface, rather than going to operators´ customer service centers. In this way, the workload of terminal maintenance is greatly reduced.

    (3) Intelligent Adjustment of System Parameters—Effectively Enlarging the Coverage
    ZTE´s CDMA WLL system is able to sense the changes of the BTS load and the quality status of the wireless environment where a terminal is located. Therefore, it is able to dynamically adjust the related radio parameters, including channel gains control, initial transmitting power of the forward fundamental channel and access parameters. On the condition that service quality of the subscribers is known, the coverage of a BTS can be maximized.

    (4) Flexible Networking and Transmission Modes
    According to the characteristics of different areas covered, ZTE´s CDMA WLL system supports multiple networking modes, such as star, daisy chain, ring and hybrid modes. Therefore, it can easily achieve the application of “one link through”. That means, when a transmission link is deployed, a number of BTSs can then be deployed along the link to attain the maximum coverage at the lowest cost and in the shortest time.

• Star Mode
  As shown in Figure 4, the star mode features simple networking, as well as convenient maintenance and installation. It is applicable to metropolitans with dense population.

• Daisy Chain Mode
  With the daisy chain mode as shown in Figure 5, one site can be equipped with multiple BTSes, which greatly reduces the number of transmission equipment. It is applicable to areas in the shape of strips, with less dense population.

• Hybrid Mode
  For an actual project, multiple networking modes can be combined into a hybrid mode to suit the specific situation of a site, as shown in Figure 6. Moreover, ZTE´s CDMA WLL network supports multiple transmission modes, including microwave, Broadband Wireless Access (BWA), satellite, coaxial cable, optical fiber and High-bit-rate Digital Subscriber Line (HDSL). It also supports the sharing of the transmission system with other existing networks. In this way, it facilitates operators in utilizing the existing transmission system to construct their CDMA WLL networks.
  

  

    (5) Ideal Mobility Limitation Capability
    ZTE has rich experience in solution to CDMA WLL system, as well as an in-depth understanding of mobility limitation. ZTE´s CDMA WLL system can limit subscribers´ mobility within one sector, one or multiple BTSes, the administration premises of one BSC or multiple BSCs/MSCs, and the entire network.

    The system has the following features:

• Full compliance with the standard interfaces

• The mobility limitation scheme 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 based on different levels.

• There is no constraint for the home network, which solves the problem that subscribes at the edge have difficulty making phone calls.
  

    (6) Auxiliary Power Supply Solution
    The BTSs of ZTE are having small power consumption, saving the input in auxiliary power supply. The BTSes support 220 V/110 V AC input, or -48 V DC input. In the case of adopting AC power supply, it is normally an outdoor work environment, with an unstable voltage. It is suggested to select Uninterruptable Power Supply (UPS). Should power failure occurs the supply of power by UPS can be guaranteed.

     The monitoring of the UPS can be reported to the background via the BTS.

    The WLL system and the terminals can also use a solar power supply solution, which has been applied in Nepal and other countries.

    (7) Smooth Evolution and Capacity Expansion
    ZTE´s CDMA WLL equipment adopts all-IP architecture. It complies with the trend of technical development, and can smoothly evolve to Next Generation Network (NGN). It maximally protects the investment of the operators.
The Base Station Subsystem (BSS) may support CDMA 1xEV through software upgrade and the addition of the channel board that supports EV.

    The equipment adopts modular design, ensuring the system to implement smooth “building block” capacity expansion.

    (8) Diversified Terminal Types
    ZTE has developed and launched several sorts of terminals for the CDMA WLL system (as shown in Figure 7), which helps operators explore user resources at different layers.

• Fixed wireless terminals
  Developed according to the characteristics of WLL subscribers, ZTE´s fixed wireless terminals support voice, fax and data services. For wireless pay phones, they also provide terminal-charging interfaces based on pulse and polarity reversal.

• Full-spectrum wireless data cards (1x PCMCIA cards)
  These cards support high-speed packet data services.

• Vehicle mounted stations

• Data transmission modules
  The modules can be applied to such fields as power, irrigation works and weather forecast.
  

    (9) Versatile Service Functions
Supporting the following services, ZTE´s CDMA WLL system help improve the network competence and
revenue-generating capability of
the operators.

• Basic voice service

• Supplementary services

• Fax service

• High-speed data services (1X Release A: 307.2 kb/s; 1xEV-DO: 2.4 Mb/s)

• Circuit data services (14.4 kb/s)

• Wireless pay phone services (supporting polarity reversal, or 12 kHz and 16 kHz metering-pulse charging)

• Concurrent voice and data services

• Trunking services

• Location based services

• Prepaid services

• Short Message Service (SMS)

• Wireless Virtual Private Network (WVPN) services
  

    (10) Powerful Network Planning, Optimization and Project Implementation Capabilities
    ZTE is able to provide a full set of network planning and optimization software that contains road test software, network optimization software and simulation software. With hundreds of network deployment cases for large domestic and international customers, ZTE has accumulated rich experiences. In addition, ZTE is able to provide turnkey services that range from system design, network construction, network planning and optimization to system maintenance and upgrade, and technical training.

4 Extensive Applications
As of October 2005, over 30 million lines of related ZTE´s CDMA WLL system requirement has been operating on domestic and international communication networks, and the CDMA WLL system has entered the communication networks of 100 carries in approximately 60 countries. Its features of low cost, wide coverage, high quality and easy maintenance make it the best choice for the wireless access network construction of a large number of operators.

4.1 CDMA WLL Network Projects for  BSNL of India
    (1) Background of BSNL
    Bharat Sanchar Nigam Ltd (BSNL) is the No. 1 state-owned telecom operator of India. It has PSTN, GSM and CDMA networks, covering all areas except Delhi and Bombay. The CDMA WLL network of BSNL is the largest WLL network of India, with coverage over most of the country. Most of the CDMA equipment of this project came from ZTE.

    (2) Projects for BSNL
    As the largest CDMA equipment provider of BSNL, ZTE won a bid of the CDMA IS95 project of BSNL with 500 thousand lines in as early as 2002. The network is operating in 20 states, and was highly regarded by the branches of BSNL in these states. In 2004, ZTE repeated its victory in the bid of the first CDMA2000 1X network of BSNL, with the conclusion of a contract that contained 1.026 million lines of CDMA network. As the performance and stability of the equipment provided by ZTE are excellent, and the subscriber base grows rapidly, BSNL made considerable economic gains. Based on good cooperation, ZTE and BSNL signed a capacity expansion contract of 450 thousand lines at the end of 2004 and another contract of 513 thousand lines in June 2005.

    (3) Service Applications

• Voice Service
  Currently, the voice service dominates the CDMA WLL networks of India. ZTE´s equipment supports outstanding personal voice services and wireless public phone services. The equipment provides constraints at different levels, helping the operators provide personalized services to
  the customers.

• Data Services
  The subscriber can experience high-speed packet data services at the rate of 153.6 kb/s.

• EV-DO
  ZTE helped BSNL construct the first EVDO pilot office in India, which has passed the tests.

• Wide Coverage
  The countryside areas of India have the requirements of fast network construction and wide coverage. The whole portfolio of the products of ZTE, with various networking modes, enormously boosted the competence
  of BSNL.

4.2 CDMA WLL Project for Algeria Telecom with 330 Thousand Lines
(1) Background of Algeria Telecom
    Algeria Telecom is the largest fixed operator of Algeria. It inherited all the telecom operation assets of the former Ministry of Post and Telecom, with complete transmission, switching, access, and CDMA WLL network resources. It deploys fixed network phone call, international toll call, Internet, data services, and CDMA WLL services. In 2003, it started to invest in the construction of the CDMA network. Algeria Telecom is a long-term partner of ZTE. Currently its network is distributed in 47 provinces of the country, providing convenient telephone services to the people of Algeria.

    (2) Scale of the Project
    As the first CDMA equipment provider of Algeria Telecom, ZTE signed a contract of 123 thousand lines of CDMA network in July 2003, covering 43 provinces nationwide. In August 2003, ZTE concluded a contract of 110 thousand lines with the Ministry of Post and Telecom of Algeria to cover the capital area, Algiers. In 2004, the two networks mentioned above were combined, and at the end of the same year, a 100-thousand-line capacity expansion project was implemented. The network provides basic voice services, 1x EV-DO high-speed data services and rich value-added services. It is also able to smoothly evolve to 3G network. Currently the commercial number allocation is satisfactory.

    (3) Service Applications

• Data Services
  The basic data services of Algeria Telecom such as fixed station and wireless Internet access are popular in the country. Currently, its service expansion heads towards industry applications, such as ATM of the financial industry and user data transmission of the power industry.

• EV-DO Project
  To satisfy the robust data service demands in the Algerian market, ZTE and Algeria Telecom are cooperating in constructing an EV-DO network. With the network, the subscribers can enjoy high-speed network services anywhere and anytime through their wireless terminals. Simultaneously, the EV-DO network will take the place of ADSL to provide office and home Internet access, overcoming the difficulty of these services. The DO network will first cover the “hot spots” in the large cities of Algeria.

Manuscript received: 2005-08-31