Position: Flexible Applications Enabled by ZTE's OneNetwork Solution
1 ZTE's OneNetwork Solution Concept
With many years of experiences in wireless technologies, ZTE launches OneNetwork solution including unified RAN based on SDR technology, unified all-IP core network and unified OMC platform.
ZTE's unified SDR solution can support multiple radio access technologies, for example, GSM, CDMA, WCDMA, TD-SCDMA, WiMAX and LTE. With SDR solution, one set of equipment can be software configured as dual-mode or multi-mode.
The BTS equipment generally consists of two parts: Baseband Unit (BBU) and RF Unit (RU). The BBU is based on the MicroTCA architecture and adopts SDR technology to support different technologies. The frequency of RU can be flexibly adjusted within 20MHz through software configuration in 900/1800/2100/2600MHz frequency bands.
The unified all-IP core network based on the ATCA architecture separates transmission from services and enables large-capacity transmission for mobile networks.
The Unified Element Management Platform (UEP) developed by ZTE serves as the operation and maintenance system, network element management system, network management system, and service management system.
ZTE's OneNetwork solution can meet different requirements of scenarios such as 3G<E, 2G&3G<E, WiMAX<E.
2 Evolution from 3G to LTE
Some operators plan to launch 3G as soon as they get 3G licenses. But they are not clear about how to evolve to LTE in the future. The traditional 3G solution only supports single-mode RAN and the core network. If operators want to upgrade from HSPA to LTE, they have to alter most of the hardware and even build a new network. This means investing more CAPEX in the network deployments and more OPEX in the network operation.
To transform the traditional network evolution concept, ZTE launches its OneNetwork solution, which can help implement a single RAN network and core network, paving the way for LTE.
ZTE's OneNetwork solution can meet requirements of UMTS network deployments in 900MHz, 1800MHz and 2100MHz bands. After a UMTS network is built, some remaining frequency bands can be reused in the LTE deployment, or parts of UMTS frequency bands are refarmed to LTE. Below are some examples of such application scenarios.
Supposing operators owning 16MHz in 900MHz band want to firstly launch UMTS900 and refarm most of GSM900 frequency bands to UMTS900 usage. The operator can use ZTE's OneNetwork solution (as shown in Figure 1) to realize the evolution: The first step is to launch UMTS900 S111 with HSPA support and attract of the GSM subscribers. The second step is to upgrade UMTS900 network from S111 to S222 with HSPA+ support. In the future the network can evolve to LTE, requiring no massive hardware change. In order to reduce the initial investment, ZTE suggests deploying one RU per sector in the beginning. In the near future when LTE is ready for rollout, another RU will be added to support 2 x 2MIMO or 4 x 4MIMO.
Figure 1 OneNetwork solution ensures that UMTS will evolve to LTE
ZTE's OneNetwork solution can also help operators achieve the smooth evolution of the core network. All the elements in the core network are based on the ATCA platform. With a software upgrade, functions of one type of network element can be converted to those of another type of network element. The SGSN, for example, can be converted to the MME server by a software upgrade. The GGSN can be software configured to an SAE Gateway.
If operators only have 8MHz in 900MHz band, ZTE's OneNetwork solution to launch UMTS900 S111 network can be used at first. After all the subscribers switch from 2G to 3G, the remaining spectrums can be refarmed to LTE usage. Therefore, in the near future, UMTS900 S111 and LTE 1.4M S111 or S222 will coexist.
If the operators have 15MHz in 2100MHz or 1800MHz bands, they can use ZTE's OneNetwork solution to deploy UMTS S111, S222 or S333 networks initially. In the future, the operators can introduce LTE with only a software upgrade and a little hardware change.
3 Coexistence of 2G, 3G and LTE
The operators with outdated GSM equipment face the high OPEX problem. They want to swap 2G equipment with evolvable equipment, that is, equipment that supports EDGE, HSPA and even future LTE. In this scenario, the SDR or multi-mode solution is the key to success. ZTE's OneNetwork solution supports GSM/EDGE, UMTS/HSPA/HSPA+ and LTE. All the transformations from 2G to 3G and LTE are defined by software and need little hardware change.
Supposing operators owning 16MHz in 900MHz band will get 20MHz in 2600MHz band in the future. With an old GSM network, they have to swap GSM equipment with new kinds of SDR or multi-mode equipment. ZTE OneNetwork solution can meet the operators’ requirements and help them realize a step-by-step upgrade process. The first step is to launch GSM/EDGE network to replace the existing 2G network. After that, the operators can launch UMTS900 network with HSPA and HSPA+ support. In the future, when they gets 2600MHz spectrum, LTE network can be launched requiring no massive hardware change. The evolution process is shown in Figure 2.
Figure 2 Long-term coexistence of 2G/3G/LTE
In the first step, the GSM S444 network will be launched. Each sector has 20W transmit power on the top of cabinet. In the second step, the UMTS900 network will be launched, some of the 2G subscribers will switch to 3G, therefore the GSM capacity will decrease from S444 to S222.
In the future when operators get 2600MHz spectrum, LTE can be launched in a new frequency band. Finally, three kinds of networks, GSM S222, UMTS S222 and LTE S111, will coexist for a long time. The radio access network will consist of one type of base station, and the core network will be unified.
4 Conclusion
ZTE's OneNetwork solution is future proof as it can help operators achieve smooth evolution while reducing TCO. It is flexible enough to be applied in different scenarios. Up till now, ZTE's OneNetwork solution has been successfully applied by China Telecom, China Mobile, Telstra, Brasil Telecom, and other operators.
