Tokyo, October 1, 2007 — NEC Corporation announced the successful development of a new Worldwide Interoperability for Microwave Access (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.

WiMAX has been attracting attention as the next generation broadband wireless-access technology expected to enable low-cost communication services, such as high capacity mobile data communication by mobile phones and PC cards, and wide-area fixed wireless access to resolve the digital divide.

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(R), a radio propagation simulator developed by NEC for wireless LAN and 3rd generation mobile phone systems, to allow application to future WiMAX systems. The features of the newly developed radio propagation simulator RADIOSCAPE-WIMAX include the following:

(1) Accelerated calculation by hierarchized MIMO characteristic simulation technology
A large amount of complex calculation needs to be processed for WiMAX area planning that incorporates MIMO, hindering efficient area planning. To improve this process, NEC has developed the world’s 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 newly developed technology can cut this time to 1.3 days, ensuring efficient WiMAX area planning.

(2) Highly precise frequency planning by inter-sub-channel interference simulation technology
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.