NEC Develops High Speed WiMAX Radio Propagation Simulator
NEC announced the development of a new WiMAX radio propagation simulator, RADIOSCAPE-WiMAX. The new simulator is expected to realize the analysis and display of the service area and transmission performance of WiMAX systems after their adoption in Japan next year.
By introducing new space/frequency utilization concepts, such as Multiple-Input Multiple Output (MIMO) and sub-channelization, WiMAX systems are expected to realize the transmission of large volumes of data in limited-frequency bands and frequency reuse between base stations. However, existing area-planning tools cannot estimate quantitatively or precisely the effects of these kinds of new technologies, resulting in inefficient area planning. NEC has developed RADIOSCAPE-WiMAX to realize efficient area planning after the future adoption of WiMAX systems.
New functions were added to RADIOSCAPE, a radio propagation simulator developed by NEC for wireless LAN and 3G mobile phone systems, to allow application to future WiMAX systems.
To improve the process of complex calculation needs to be processed for WiMAX area planning, NEC has developed the first hierarchized MIMO characteristic simulation technology, realizing high speed and high precision simulation of increased transmission capacity by MIMO technology. For example, calculation processing for base stations located at 1km intervals in all 23 wards of Tokyo would require 52 days to be processed, but NEC's developed technology can cut this time to 1.3 days.
WiMAX employs sub-channelization, which achieves an increase in the number of frequency channels. However, interference between sub-channels differs to that of inter-channel interference in conventional radio communication, making it difficult to estimate any transmission performance degradation. NEC has incorporated an interference characteristic model into the new simulator to enable frequency planning based on highly precise interference simulations and effective utilization of limited-frequency bands.
NEC has confirmed the precision of RADIOSCAPE-WiMAX through indoor/outdoor radio propagation tests, which show that the new simulator not only maintains a high level of estimation precision similar to that of RADIOSCAPE but also achieves simulation that is 40 times faster than conventional ray-launching methods.
Utilization of this simulator will enable quantitative evaluation of system capability of specific environments and equipment during the phase of WiMAX equipment planning and system implementation. Consequently, phased equipment planning appropriate to the number of users and the volume of traffic can be achieved.
NEC is currently planning to introduce the new simulator into its total WiMAX solutions offering next year.
